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salpingectomy Surgical removal of the fallopian tube (the Latin for which is salpinx).

salpingitis Inflammation of the fallopian tubes, usually due to infection. Can be acute (e.g. gonorrhea, chlamydia and other infections) or chronic (e.g. persisting chlamydia, tuberculosis, various fungus infections). Leads to blockage of the tubes and peritubal adhesions if not treated promptly and effectively with antibiotics. See also pyosalpinx, hydrosalpinx and salpingitis isthmica nodosa.

salpingitis isthmica nodosa A nodular (‘nodosa’) thickening of the fallopian tube’s isthmus (‘isthmica’), probably due to previous salpingitis. Can cause localized obstruction of the tube and, if the obstruction is partial, an ectopic pregnancy can be caused. Overcomeable with microsurgery (see tubal anastomosis) or tubal canalization.

salpingogram An x-ray of the fallopian tubes. See hysterosalpingogram and selective salpingogram.

salpingolysis Microsurgery to remove peritubal adhesions or perifimbrial adhesions. See also fimbriolysis, with which the term “salpingolysis” overlaps. Sometimes carried out at laparoscopy. A full description can be found in WebPage 13.

salpingoscopy Looking inside the fallopian tube with a fiberoptic instrument through its relatively wide outer fimbrial end. Carried out at laparoscopy or laparotomy. See also falloposcopy.

salpingostomy Microsurgery to make a permanent, new opening at the outer fimbrial end of the fallopian tube after it has become blocked (see hydrosalpinx) from salpingitis or, uncommonly nowadays, from fimbriectomy. Sometimes attempted at laparoscopy, though mostly with a reduced chance of success. See also fimbriolysis. A description of the operation is given in WebPage 13.

salpingotomy An operation involving a temporary opening length-wise along (usually) the ampulla of the fallopian tube, usually for the treatment of a (tubal) ectopic pregnancy. Occasionally performed for a pyosalpinx. Can be carried out efficiently at laparoscopy.

SCNT See somatic cell nuclear transfer.

SCSA See sperm chromatin structure assay.

secondary The word is used medically in one of three ways: (1) part of a sequence, as in primary follicle, secondary follicle, tertiary follicle; (2) when a person has a precedent for a contrary state (e.g. secondary amenorrhea, when a woman has had at least one spontaneous menstrual period, but then menstruation stops; secondary dysmenorrhea means periods that have painful after having been not so -- or not-so-much; secondary infertility means having trouble getting pregnant despite having become pregnant successfully in the past); or (3) when the source of dysfunction lies elsewhere (e.g. secondary ovarian failure means ovaries that do not function because, in this example, the pituitary gland on which the ovaries depend is not functioning). See also primary.

secondary amenorrhea Absent periods (amenorrhea) when a woman has had at least one previous spontaneous menstrual period, but then menstruation stops. See also secondary.

secondary follicle The second stage of growth of the follicle, in which the egg (as a primary oocyte) is enclosed by a layer that’s more than one cell thick of round-shaped, multiplying follicle cells. Virtually all secondary follicles will go on to become tertiary follicles.

secondary infertility Trouble getting pregnant (infertility) in someone who has previously had a successful or potentially successful pregnancy. Although the exact definition of secondary infertility can vary among gynecologists, for me the distinction between secondary infertility and primary infertility is most useful if the term secondary infertility is restricted to when there has been a prior induced abortion (which, the odds are, would otherwise have developed normally) or a successful pregnancy; a prior ectopic pregnancy or a prior miscarriage is, in my view, still the state of primary infertility.

secondary oocyte The form of the oocyte, or egg, produced from the primary oocyte late in the life of the maturing follicle, just before ovulation. The egg stays at this stage until fertilization by a sperm cell (spermatozoon). See also meiosis.

secondary ovarian failure Failure of ovulation along with low estrogen production from the ovaries because of insufficient signalling from the pituitary gland by its hormones, the gonadotropins.

secondary spermatocyte The form of the sperm cell in the second stage of spermatogenesis (through which the sperm cells are formed in the testes), produced from primary spermatocytes in the first cell division of meiosis, and giving rise to spermatids, which have just half the normal cell’s complement of chromosomes, through the second division of meiosis; enveloped by Sertoli cells in the testicular tubules.

secretory phase The phase of development of the endometrium during which, after the proliferative phase, the endometrium stops growing but starts producing secretions (which nourish an implanting embryo) under the influence of progesterone, so it corresponds with the luteal phase in the ovarian cycle.

selective catheterization An x-ray-directed technique for placing fine catheters in veins of the body to sample the local production of hormones from a particular gland.

selective feticide See fetal reduction.

selective salpingogram An x-ray like a hysterosalpingogram in which a catheter is passed through the cervix and uterus, and then wedged into the fallopian tube to fill it with fluid visible on x-ray. High pressure can be applied, so some tubes that seem blocked on hysterosalpingogram (or on passing dye at laparoscopy) can be shown in fact to be open.

semen analysis Formal name for a sperm count.

semen sperm antibodies A test for detecting sperm antibodies in semen.

semen Fluid produced by the male genital tract at ejaculation. Contains spermatozoa, as well as many other substances, including those that make the ejaculate coagulate (and then called a coagulum, which is given time to liquefy before a semen analysis is done on it). Sperm cells account for only about 1 percent of the volume of the ejaculate, so it’s not possible to be confident about a man’s sperm count just on the basis of the volume of the semen ejaculated.

seminal fluid See semen.

seminal vesicles Male sex organs that are joined to the vas deferens on each side as they enter the prostate gland to join the urethra; once thought to act as receptacles for storing sperm, they are now known to be more important for contributing constituents of semen.

septate uterus See uterine septum.

septum Latin for a wall’. For an example, see uterine septum.

serological test for syphilis One of a number of tests to detect previous or untreated syphilis, an important (though nowadays rare) cause of birth defects and recurrent miscarriages. The chance of detecting unsuspected syphilis might be very low, but the penalty for missing it is very high, so it’s still a routine test in early pregnancy. Tests are done on serum and include the Venereal Disease Research Laboratory (VDRL) test and the Wasserman reaction (WR) test. Often tested as part of a screen for infectious disease before assisted conception, although there is no evidence that syphilis is transmitted through eggs or sperm (it is caught from contact between the lining of the vagina and the surface of the penis).

Serophene Clomiphene made by Serono.

serosa The delicate, one-cell-thick outside lining of an organ in the body, particularly (for our purposes in this book) the organs of the peritoneal cavity. Unlike other body surfaces such as the skin and the lining of the stomach or intestines, an ulcer (or missing patch) of the peritoneal serosa always heals in 8 days, however big the ulcer, or defect, is. See also peritoneal adhesions and peritoneum.

Sertoli cell Cells in the testis lining the testicular tubules that nurture the developing sperm cells; responsible in fetal life for the production of anti-Müllerian hormone, which stops the male fetus from developing fallopian tubes, a uterus and a vagina. A source of estradiol in men.

serum That part of blood that’s left after it clots. Distinct from plasma, which is that part of unclotted blood that remains on top when blood is spun down in a centrifuge (which will still clot and leave serum unless an anticoagulant is added). Various serum tests (tests done on serum, also called blood tests), are described in this dictionary.

serum 17-hydroxyprogesterone 17-hydroxyprogesterone is formed from progesterone in the adrenal glands (mostly as an intermediary substance on the way to making the adrenal’s main hormone, cortisol) and in the ovaries (on the way to making androgens and estrogens). A congenital lack of one or other of the enzymes needed to make cortisol in the adrenal causes androgens to be made instead, in turn causing hirsutism and oligomenorrhea in women, maybe with the polycystic ovary syndrome (in mild cases), or (in severe cases) causing intersex at birth. The adrenal glands enlarge in an attempt to maintain production of cortisol (hence congenital adrenal hyperplasia, CAH). An inappropriately high level of 17-hydroxyprogesterone in serum is diagnostic of CAH.

serum AFP See serum alpha fetoprotein.

serum alpha fetoprotein Measurement of alpha fetoprotein in blood serum. High levels can indicate a birth defect involving the brain or spinal cord, such as anencephaly or spina bifida (confirmed if amniocentesis shows high AFP levels in the amniotic fluid). Low levels can indicate an increased risk of Down syndrome (or trisomy 21), trisomy 18 and, occasionally, Klinefelter syndrome, signaling the need for a karyotype of the fetus’s tissues by chorionic villus sampling (CVS) or amniocentesis. The formation of AFP in the early embryo is described in WebPage 4. See also triple test.

serum anticardiolipin antibody A test done to investigate recurrent miscarriages. See anticardiolipin antibody and lupus anticoagulant.

serum antigliadin antibodies Antibodies to gliadin, a component of dietary gluten, and present in wheat, barley, rice and oats, found in celiac disease, a defect of intestinal absorption caused by abnormal sensitivity to gluten.

serum CA125 antigen Measurement of CA125 antigen in serum. A test done to investigate, particularly, adenomyosis and cancer of the ovary. Levels can also be increased with endometriosis (especially when there is a “chocolate cyst” present), during normal menstruation and during normal early pregnancy.

serum chlamydial antibodies A blood test to detect prior exposure to chlamydia. The antibodies commonly examined are not completely specific for the particular chlamydia organism that causes salpingitis and which is transmitted sexually: other chlamydia-like infections of the lungs and other regions of the body, and even some completely unrelated infections with non-chlamydial organisms can produce false positive tests; a negative test, that is an absence of detectable chlamydial antibodies, is however reassuring.

serum copper Done to screen for Wilson’s disease, in which there is abnormal retention of copper in the body -- a rare cause of recurrent miscarriages.

serum creatinine See serum urea and creatinine.

serum estradiol Measurement of estradiol in blood serum. Used especially for monitoring the development of ovarian follicles in assisted conception, usually together with transvaginal ultrasound. The cycle might be a natural one or, more usually, when there is ovulation induction or superovulation. The result should be available within 4 hours of the test for this purpose. For a diagram showing how serum estradiol levels change during the ovarian cycle, see WebPage 3. Abbr. serum E2.

serum free testosterone The direct measurement of the small proportion of testosterone that is not bound in the blood to carrier proteins such as sex hormone binding globulin, and so is available directly to the tissues. A more sensitive and specific test than serum testosterone.

serum FSH Measurement of follicle stimulating hormone in serum. Useful at the time of menstruation for indicating a significantly decreased number of eggs in the ovaries in the few years leading up to menopause (that is, indicative of depletion of eggs or primary ovarian failure); see also low responders. Continuously high in women after menopause, and then excreted in high amounts in the urine (from which, in turn human menopausal gonadotropin is derived). For a diagram of how serum FSH levels change during the ovarian cycle, see WebPage 3.

serum hCG Measurement of human chorionic gonadotropin in serum: essentially a pregnancy test, but carried out more precisely (quantitatively) than is the case with a yes or no test (which is qualitative). Often carried out serially, to determine if a pregnancy is: thriving (hCG levels double every two or three days in normal early pregnancy ; languishing (levels rise more slowly, seen with an ectopic pregnancy and with an inevitable miscarriage); or resolving naturally (levels that are falling). Very high levels are seen with hydatidiform mole. Part of the triple screen used to screen for Down syndrome in early pregnancy.

serum HIV antibodies A test for HIV, the virus that causes AIDS, and which comes in two strains, type 1 and type 2. They need separate tests, but mostly both are done as a routine. The test looks for the development of an immune reaction against the virus, it does not look for the virus itself, so it’s possible, for a few weeks, to have been infected (and to be infective to others) with the test itself still a negative test, that is, apparently (but falsely) clear.

serum inhibin B In women, when measured during menstruation, inversely related to the serum FSH (and probably provides no more information than the day 3 FSH level in predicting depletion of eggs); in men with azoospermia, levels predict the likelihood of being able to obtain sperm for ICSI at testicular sperm extraction. See also inhibin.

serum LH Measurement of luteinizing hormone in blood serum. Used in monitoring to judge the occurrence of the LH surge, if GnRH-analogs have not been employed. The result should be available within 4 hours of the test for this purpose. For a diagram showing how serum LH levels change during the ovarian cycle, see WebPage 3.

serum progesterone Measurement of progesterone in serum. The rise and fall of serum progesterone in the ovarian cycle is shown in a diagram in WebPage 3: it is low in the follicular phase, rises with ovulation, and is elevated through the luteal phase, falling prior to menstruation. Often measured to check the occurrence of prior ovulation (see also premenstrual endometrial biopsy). Used to infer the onset of ovulation in ovulation induction or assisted conception programs, and attaches extra significance to an apparently raised serum LH in judging the onset of the LH surge during monitoring. The result should be available within 4 hours for these purposes. Abbr. serum P4.

serum prolactin Measurement of prolactin in serum. An increase is called hyperprolactinemia.

serum sperm antibodies Estimation of sperm antibodies circulating in the blood. Generally not as useful as estimating semen sperm antibodies (for men) or cervical mucus sperm antibodies (for women), as these fluids have more immediate contact with sperm cells.

serum testosterone Measurement of testosterone, the chief male sex hormone (androgen) circulating in the blood serum. If increased in women with oligomenorrhea or amenorrhea, indicative of the polycystic ovary syndrome. The free androgen index and free testosterone are more sensitive tests.

serum tissue transglutaminase antibodies See celiac disease.

serum TSH Measurement of thyroid stimulating hormone in serum. See thyroid function tests.

serum urea and creatinine A test of kidney function. Sometimes measured when screening for a kidney (renal) cause of recurrent miscarriages.

sex Sexual intercourse (coitus or having sex) or, gender or relating to it (as in sex chromosome). For more on what positions affect getting pregnant (most don’t!), see orgasm and the box, Positioning missionaries for sex.

sex chromosome A chromosome that’s either the X-chromosome (a pair confers femaleness in a normal diploid complement of chromosomes) or the Y-chromosome (just one confers maleness in a normal diploid complement of chromosomes); distinct from the non-sex chromosomes, or autosomes (which are numbered from 1 to 22); aneuploidies give rise to Turner syndrome, Klinefelter syndrome, triple-X syndrome, extra-Y-chromosome syndrome) etc; examined in a karyotype.

sex hormone binding globulin The main carrier protein in the blood for the hormone testosterone; measured in conjunction with the serum testosterone to derive the free androgen index.

sex-linked recessive inheritance See recessive inheritance.

sexual reproduction Replication of a diploid organism after combination of haploid male and female gametes, each of which has been produced through the process of meiosis, thus assuring a reassortment of the alleles present among the two parents, in the form of a new, unique, individual genome. Preserved with in vitro fertilization despite the absence of sexual intercourse. The opposite to cloning.

short protocol A treatment protocol for controlled stimulation of the ovaries using GnRH-agonists with injections of follicle stimulating hormone (FSH) for induction of superovulation in assisted conception programs involves starting the GnRH-agonist a day or two before the injections of FSH start. The advantage is one of cost: less FSH (and less GnRH-agonist) are used compared with the long protocol. The disadvantage is that luteinizing hormone levels and progesterone levels can rise, possibly (in some cycles of treatment) spoiling optimal development of ovarian follicles. The GnRH-agonist is continued (in contrast to the ultrashort protocol) until follicles are mature and human chorionic gonadotropin is given to start the process of ovulation. The details are in the box, The long, short and ultrashort of GnRH-agonists, in WebPage 20.

Simms-Huhner test See postcoital test.

small bowel The small intestine, leading out of the stomach; narrower but longer than the large intestine (or colon), to which it connects. See also bowel.

small-for-dates A general term used by obstetricians or pediatricians to refer to a fetus or newborn baby that seems smaller than it should be for the assumed duration of the pregnancy so far. The three main causes are a genetic abnormality of the fetus; insufficient nutrition for an otherwise normal fetus; and an incorrect calculation of the dates, maybe because ovulation and conception took place later than the usual two weeks after the last menstrual period. Recent research shows that women with infertility might be at higher risk of small-for-dates babies when they do get pregnant.

SMI See sperm microinjection.

somatic cell Any cell that forms the tissues and organs of the body that is not a germ cell. Derived from soma, the Greek for body.

somatic cell nuclear transfer (SCNT) Transfer of the nucleus of a somatic cell into a secondary oocyte or zygote from which the egg or zygote's chromosomes have been removed, in such a way that cleavage still occurs, in effect causing the cell's nucleus to “bud”, or reproduce without genetic recombination, and hence a form of asexual reproduction or cloning now commonly used for reproductive cloning in animals and, it is hoped, for therapeutic cloning to create embryonic stem cells for treatment of serious degenerative disease and cancers.

spastic colon syndrome See irritable bowel syndrome.

sperm Common abbreviation for spermatozoon (or for the plural form, spermatozoa). Also used in the form sperm cell. For more on immature sperm cells, start with spermatid. See also sperm count. Plural: sperm or spermatozoa.

sperm antibodies The result of a reaction of the immune system against sperm cells (spermatozoa) and, by limiting the ability of sperm to show motility, a contributory (or occasionally the only) cause of infertility. Can be present in serum (see serum sperm antibodies), in cervical mucus or in semen. Can be agglutinating (which make sperm stick in clumps), immobilizing (which cripple sperm particularly effectively and kill them), or coating, which interfere with sperm attachment to the zona pellucida of the egg (the secondary oocyte), preventing fertilization. The screening test for sperm antibodies involves immunobeads. To learn how virgins can develop antibodies to sperm, see WebPage 10.

sperm chromatin structure assay (SCSA) A measurement of the proportion of sperm cells that have damaged DNA. Fewer than 15% is consistent with normal fertility; 15%-30% can result in subfertility; and more than 30% may cause sterility or recurrent miscarriage.

sperm count A semen analysis, measuring the volume of the ejaculate, the density of spermatozoa (“sperm cells”, or just “sperm”) in it (expressed as so many million sperm per milliliter), the proportion of sperm swimming normally (the motility), and the proportion with a normal shape. A normal sperm count consists of a volume of more than 1 ml; a density of more than 20 million per ml; a motility of more than 50 percent; and normal forms of more than 50 percent (casual examination) or more than 14 percent (critical examination by the strict criteria recently advocated by the World Health Organization). For the effects of frequent sex on sperm counts (as well as other aspects of collecting semen for the test), see WebPage 5. For more on the question of a possible world-wide decline in sperm counts over the last generation, see WebPage 10.

sperm microinjection Either intracytoplasmic sperm insertion (ICSI) or subzonal insertion (SUZI, now obsolete). (Abbreviated SMI, although no longer in common usage.)

sperm wash See capacitation.

spermatid The product of the spermatocyte in the testis when it has completed meiosis (by which the number of chromosomes is halved, so it’s in the haploid state), and also enclosed in the testicular tubules by the Sertoli cells. Early spermatids are round-shaped, whereas late spermatids closely resemble mature spermatozoa. See also spermiogenesis.

spermatocyte The sperm cell equivalent to the oocyte stage of the egg. See also primary spermatocyte, secondary spermatocyte and spermatogenesis. Further development in the testicular tubules results in a spermatid.

spermatogenesis Development of a sperm cell, in the tubules of the testes (the testicular tubules), from spermatogonium and spermatocyte to spermatozoon (the last part of this process, from spermatid to spermatozoon, is called spermiogenesis). The process of spermatogenesis takes 56 days. At any one location in a tubule there are cells at four different stages of maturity (see WebPage 3), so mature sperm are released from a particular location into the lumen of the testicular tubules every 14 days. A systematic interruption of spermatogenesis results in azoospermia and is called maturation arrest.

spermatogonium The replicating phase of the sperm cell in the testis, equivalent to the oogonium in the ovaries, but, unlike the oogonia, spermatogonia normally persist until old age. Located among the supporting cells (Sertoli cells) in the testicular tubules. Divides by the process of mitosis until it begins to undergo meiosis by changing into the primary spermatocyte, the first step in the process of sperm cell formation, or spermatogenesis. Plural: spermatogonia.

spermatozoa Plural of spermatozoon.

spermatozoon The final stage of development of the maturing sperm cell, as it leaves the tubules of the testis (the testicular tubules, to mature in the epididymis. Composed of a head (including the acrosome), a midpiece loaded with mitochondria to provide energy, and a tail, or flagellum (see also cilium), for propulsion. Packed into the head of the spermatozoon is a haploid number of chromosomes (there are normally 23, including either an X-chromosome or a Y-chromosome). See also sperm count and fertilization.

spermiogenesis The final part of the formation of a mature sperm cell, in which the round, early spermatid (already with a haploid number of chromosomes) loses its round shape to acquire the features of the mature, elongated spermatozoon. Contrast with spermatogenesis, which encompasses spermiogenesis as it's completed.

Spinnbarkheit One of the measurable qualities of cervical mucus that indicates receptiveness to sperm. German for “ability to be spun’, meaning stretchability.

spontaneous abortion See miscarriage.

statistical significance A point at which statistics indicate that a set of measurements or observations does not just actually differ from normal (i.e. it’s abnormal) or from a control group, but that the observed difference is unlikely (typically less than a 1-in-20 risk) to have come about just by the effects of chance (we then say that there is a P-value -- for Probability -- of less than 0.05 ... which is what 1-in-20 is when expressed as a proportion). Footnote: One logical follow-on from this is that if you study 20 different variables for such statistical significance the odds are that one will have a P-value less than 0.05, just by the expectations of chance! In practice, when multiple observations like this are being made statisticians will put a tougher criterion on what is “statistically significant', such as P less than 0.02 or 0.01. For academic legitimacy, P values should be set before looking at the data, not afterward. For more, see the box, “Significant” or “important”.

statistics (As in “lies’, “damned lies’, and “statistics’.) The science -- and art -- of using arithmetic and probability theory to work out how likely an association between sets of measurements or between sets of observations is to have happened by chance alone. See also statistical significance.

STDs Sexually transmitted diseases, such as gonorrhea, chlamydia and HIV.

stem cell A relatively undifferentiated cell in any tissue responsible for replenishing cells lost from a tissue through normal wear and tear, in the case of adult stem cells, or responsible for virtually all of a fetus's cells, in the case of embryonic stem cells; characterized by being able to replicate (through mitosis) seemingly for ever, either in the body or in tissue culture, without wearing out the ends of the chromosomes. Embryonic stem cells are controversial because they are derived from human embryos, sometimes by the process of somatic cell nuclear transfer, which involves creating embryos or embryo-like forms of a kind that could be used for reproductive cloning. The word stem comes from analogy with the stem of a plant giving rise to branches and further branches, representing the ever-increasing number of different paths a stem cell can differentiate into.

sterility The state of absolute infertility or complete infertility, with no chance of getting pregnant without special help. Causes include azoospermia, anovulation (especially primary ovarian failure), and blocked fallopian tubes. (Although words like sterility and sterile sound insensitive, especially for a book like ours, it’s important in medicine to avoid ambiguity; see the box, Medical vocabulary -- sensitive, precise and correct?, for a discussion of the medical author’s dilemma.)

sterilization reversal An operation involving microsurgery to rejoin the healthy ends of the fallopian tubes or vasa deferentia to reverse the effects of a previous sterilization operation. See also tubal anastomosis and vasovasostomy.

sterilization An operation designed to induce sterility. In men, usually carried out by removing small segments of each vas deferens (vasectomy); in women, usually carried out by removing, clipping or otherwise destroying a small segment of each fallopian tube, preferably close to the uterus (often called tubal ligation). See also fimbriectomy.

strict criteria See sperm count.

subclinical miscarriage An early miscarriage, usually within a week or two of the period that had been expected. Traditionally, no curettage was needed; these days a subclinical miscarriage is one that has not resulted in a gestational sac visible on transvaginal ultrasound.

subfertility Infertility that is not “absolute', or “complete infertility” -- that is, there is a chance of pregnancy: it is not sterility (these last 3 terms are synonyms) -- but the chance of getting pregnant each month (fecundability or monthly fertility) is reduced. More or less definite causes can include oligospermia, polycystic ovary syndrome and other causes of oligomenorrhea, endometriosis, peritubal adhesions, fibroids (especially submucous fibroids) and increased age, especially of the woman. Subfertility is the subject of WebPage 7. See also cumulative chance of pregnancy and K-selection. Synonymous with relative infertility.

submucous fibroid A fibroid (or myoma) that grows from the wall of the uterus inwards to distort the endometrial cavity. Can be a cause of menorrhagia (heavy periods), intermenstrual bleeding, premenstrual spotting, infertility and miscarriage. See also myomectomy.

submucous myoma See submucous fibroid.

subseptate uterus See uterine septum.

subserous fibroid A fibroid (or myoma) that grows from the outside surface of the uterus, into the cavity of the abdomen, or peritoneal cavity. The least likely of any sort of fibroid to affect reproduction, but can cause symptoms of pressure or pain should it twist or degenerate suddenly. See also myomectomy.

subserous myoma See subserous fibroid.

subzonal insertion (SUZI) An obsolete IVF technique involving sperm microinjection, in which one or more sperm are injected through the zona pellucida into the perivitelline space of the egg (the secondary oocyte. Not very effective, because its efficiency is limited by sperm having to have undergone the acrosome reaction). Nowadays completely replaced by intracytoplasmic sperm insertion (ICSI), where the acrosome reaction is not a requirement.

suffering The prevention from and alleviation of personal suffering by a patient is the physician’s ultimate duty and the principal purpose of the professional practice of medicine. The suffering can be physical or mental. The ethical values of beneficence, non-maleficence, justice and equity, for many thoughtful physicians, become subordinate to the duty of making the patient better. For the infertile couple, prevention from or relief of suffering most obviously means the physician helping them to have a baby; this is not always possible, however, in which case other medical and personal strategies need to be explored if the suffering is to be lessened. These themes are developed in WebPages 25 and 26.

superovulation Intentional induction of multiple ovulations at once, using injections of follicle stimulating hormone and human chorionic gonadotropin, for assisted conception. Inevitably there is a risk of multiple pregnancy unless egg retrieval is performed. See also ovulation induction, ovarian hyperstimulation syndrome (OHSS) and follicular recruitment (specifically, late or cyclical follicular recruitment).

Suprefact See buserilin.

surrogate “A person who acts for or takes the place of another” [Oxford English Dictionary]. In reproductive medicine, a woman who has a baby on another woman’s behalf. See also gestational surrogacy, traditional surrogacy, and collaborative reproduction.

SUZI See subzonal insertion.

sympathy See empathy for a discussion of its place in the range of feelings one person can have for another.

Synarel A GnRH-agonist, made by Syntex. Administered as a nasal spray.

syncytiotrophoblast The component of the trophoblast bathed by maternal blood in the placenta (and thus covering the chorionic villi). Derived by differentiation and fusion of cytotrophoblast cells, so the syncytiotrophoblast only ever comprises just one cell (albeit with very many cell nuclei), through which almost everything reaching or leaving the embryo or fetus must pass. By the end of normal pregnancy, its area is about 12 square meters, or over 100 square feet. Most hormones and proteins produced by the placenta, such as progesterone, hCG and PAPP-A, come from it. See also lacunae.

syngamy If fertilization is the “marriage” between egg and sperm then syngamy is its “consummation’, as the male and female pronuclei come together for the respective haploid sets of chromosomes to combine into a diploid set. An event of legislative importance in the conservative Australian state of Victoria, after which permission for embryo research becomes much harder to obtain, whatever the views of the couple concerned or an ethics committee might be.

syphilis See serological test for syphilis.

 

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T cells White blood cells or lymphocytes that are part of the immune system concerned with recognizing and dealing with foreign or abnormal cells discovered in the body's tissues. See also NK cells.

take-home-baby rate The percentage of treatment months (or treatment cycles in assisted conception) that result in the woman taking home one or more babies (twins are not counted separately, though!); the statistic of most interest to patients and, in an age of skepticism in the community, the most politically correct statistic for reproductive medicine clinics to quote, but it’s less useful for clinics’ quality control purposes than the conception rate, the implantation rate, and the viable pregnancy rate, because: (1) it excludes obstetric misadventures often beyond the control of the infertility clinic; and (2) there is a long lag before it can be calculated, making results at best about 9 months old.

teleological ethics A set of ethical beliefs based on the goodness or badness of consequences, whether actual, intended or predicted. For purposes here, restricted to consequences to individuals, in contrast to utilitarian ethics. Open to change according to empirical observation of outcomes (hence “evidence based ethics”). For practical application, and a contrast to deontological ethics and utilitarian ethics, read the box, Ethics: Moral imperatives, outcomes and equity, in WebPage 26.

teratozoospermia See oligospermia.

tertiary follicle The third stage of growth of the follicle, in which the egg is enclosed by a thick layer of round-shaped follicle cells among which an antrum, or fluid-filled space, has formed; this antrum will come to dominate the size of the follicle. The first stage of the follicle visible with transvaginal ultrasound (when it reaches about 4 mm in diameter). Further growth of the early tertiary follicle is determined by follicle stimulating hormone. Synonym: antral follicle.

TESE See testicular sperm extraction.

TEST See tubal embryo stage transfer.

testes Plural of testis.

testicle Diminutive of testis: the terms are interchangeable.

testicular biopsy A biopsy of the testis to work out the reason behind an absence of sperm cells (azoospermia). Also used for testicular sperm extraction (TESE).

testicular feminization A state of intersex in which the karyotype is male (i.e. 46,XY), the gonads are testes (hence also male), but the body is completely unresponsive to testosterone and to its metabolite dihydrotestosterone, so it develops in the female way, with a normal vulva and vagina apparent at birth, and with normal development of the breasts at puberty. Because the testes still secrete anti-Müllerian hormone, there’s no uterus. Invariably these children are raised as girls, normal except for their primary amenorrhea and their infertility. Specialist medical supervision is needed, because there is an increased risk of cancer in the abnormal gonads. Synonymous with androgen insensitivity syndrome (complete form).

testicular sperm extraction Dissection into the testis itself, in men with azoospermia due to maturation arrest, to recover (by “teasing out’) immature sperm cells from the (often small) fraction of testicular tubules there which still contain such cells. The sperm cells are used for in vitro fertilization using intracytoplasmic sperm insertion (ICSI). Abbreviated TESE.

testicular tubules The main constituent of the testis, lined by Sertoli cells and containing the developing sperm cells. Lying between the tubules are the interstitial or Leydig cells. See also spermatogenesis.

testis The male gonad, located normally in the scrotum. Produces the hormone testosterone as well as the male germ cells, or spermatozoa. Interchangeable with testicle. Plural: testes.

testosterone The main male sex hormone, or androgen, in the blood (where it is measured as serum testosterone). Secreted in large amounts by the testis in a man. Before it acts on the tissues it must be converted to dihydrotestosterone. Present also in women, being converted from the weaker androgen androstenedione.

tests for tubal patency Tests that check if the fallopian tubes are open, usually by passing fluid through the cervix to fill the endometrial cavity and then demonstrate it coming out the ends of the tubes. The two common tests are to pass a blue dye at laparoscopy or a solution opaque to x-rays, namely a hysterosalpingogram. Once upon a time, carbon dioxide gas was used and listened for with a stethoscope (a Rubin’s test); a high-tech version of Rubin’s test uses transvaginal ultrasound to show the gas. See also falloposcopy. The treatment of tubes shown to be obstructed on patency testing with microsurgery is detailed in WebPage 13.

theca interna A layer of cells in the ovary lying immediately around the follicle; under the influence of luteinizing hormone it’s responsible for producing the weak male sex hormone androstenedione, which is then (1) converted by the follicle cells (the granulosa cells) into estrogen, principally estradiol, or (2) converted by other tissues outside the ovary to testosterone.

thecal cells Cells that make up, or come from, the theca interna.

therapeutic cloning The use of somatic cell nuclear transfer to produce embryonic stem cells suitable for differentiation into tissues that are a perfect match to treat disease in the person who provided the cell nucleus used. Ethically controversial.

threatened miscarriage Traditionally, any bleeding from the uterus during pregnancy while the cervix is (still) closed. Today, as well, there would need to be a normal embryo and, a little later, normal fetal heart movement pattern on transvaginal ultrasound to separate it from an inevitable miscarriage.

three-dimensional ultrasound A computer enhanced transvaginal ultrasound or a multi-probe abdominal ultrasound that produces a composite, constructed three-dimensional image of the uterus, which can then be viewed from any perspective. Excellent for displaying the form of the uterus in the investigation of uterine anomalies and recurrent miscarriages.

thrombin An enzyme present in the blood that, when activated by tissue injury, causes blood to clot. See also coagulation system and fibrinogen.

thrombophilia An increase in the tendency of the blood to clot, as in “thrombosis”. In primitive, evolutionary times, a survival advantage for women giving birth, when loss of blood would on average be less, but exacting a price in terms of increased risk of stroke or venous thrombosis. The thrombophilias are implicated in disturbances of pregnancy, including recurrent miscarriage and stillbirth.

thyroid function tests (TFTs) Usually two tests: a serum u (low for underactivity, high for overactivity) and a serum thyroid stimulating hormone (TSH, high for underactivity based primarily in the thyroid gland, low for overactivity based primarily in the thyroid gland and low for underactivity based in the pituitary gland). As a screening test for malfunction of the thyroid gland a serum TSH will generally be enough.

thyroid stimulating hormone (TSH) A hormone produced by the adenohypophysis (the front, glandular part of the u) that switches on the thyroid gland, causing it to make and release thyroxine. See also thyroid function tests.

thyroxine The main hormone of the thyroid gland, responsible for controlling the rate of metabolism in the body; activity of the thyroid gland is measured with thyroid function tests.

time left for conception One of the two most important variables that determine the chance of still getting pregnant naturally in subfertility and unexplained infertility (the other is duration of infertility). The longer the time still available the better the chance that, sooner or later, pregnancy will happen. Broadly limited by the female partner’s age, but personal circumstances and ambitions within the biologically available timeframe might shorten it, leading to a decision to seek treatment with assisted conception. Explained in Appendix 1. See also fecundability.

time to pregnancy An estimate of likely fertility in secondary infertility, where the time it took to get pregnant the first time is used as a very approximate guide to what might be expected next time round. Of limited usefulness, but if it took a long time to get pregnant the first time it will typically take at least as long next time. Achieving a pregnancy does not usually itself permanently cure subfertility.

TMC Abbreviation for threatened miscarriage.

torsion Twisting of an organ on its vascular pedicle, risking necrosis. Can happen to the testis in boys, especially after an injury to the scrotum, or to the ovary and fallopian tube, either spontaneously during adolescence or when enlargement from superovulation has produced u (OHSS), as described in the box, Twisted ovaries, in WebPage 12. An operation to untwist it can save the affected organ, if carried out quickly enough.

totipotent See pre-embryo.

traditional surrogacy Surrogacy in which the woman who is the surrogate for the intended pregnancy provides the eggs (through her own ovulation); is impregnated by assisted insemination; carries (or “gestates’) the pregnancy; gives birth; and then gives up the baby to the person who commissioned the surrogacy arrangement. Also known as genetic-plus-gestational surrogacy. The surrogate is as much the biological mother of the child as if she had conceived in natural circumstances, except that the male by whom she has been impregnated has no prior social relationship with her. No countries other than the US, where commercial surrogacy can be legal, have encouraged the practice, whether for altruistic or commercial reasons. For tribal society and biblical precedents, see WebPage 23.

transsexual An individual with a gender identity that is opposite to that conventionally associated with his or her biological sex. Not to be confused with intersex or with sexual preference.

transsexualism See transsexual.

transvaginal ultrasound Ultrasound imaging of the pelvic organs for diagnosing abnormalities of (particularly) the uterus and the ovaries; for monitoring the development of ovarian u with ovulation induction and assisted conception programs; and for following the course of early pregnancy. Among the pioneers were Dr Karl Popp, who used a mechanical sector scanner vaginally in Hamburg in 1984, and Dr John Anderson, who used the first vaginal linear array scanner at Sydney IVF in 1985, leading to its widespread use subsequently in Australia and the US.

trial wash See sperm wash.

Tridomose See gestrinone.

trimester Literally, a three-month period of time; so the nine months of pregnancy are divided into the first, second and third trimesters. Most u take place in the first trimester (up to 12 or 13 weeks). Pregnancies that reach the third trimester (beyond 27 weeks) have an increasingly good chance of being viable (though nowadays, with intensive care, survival has occurred from about 24 weeks).

triple screen See triple test.

triple test A screen for congenital abnormalities of the fetus done on the mother's blood serum during pregnancy to look for fetal trisomy, including Down syndrome. The original test comprised measurements of (1) serum alpha fetoprotein (decreased in the trisomies), (2) serum hCG (increased in trisomy 21, decreased in trisomy 18), and (3) serum estriol (decreased in trisomy 21, increased in trisomy 18). Note that only 60% of pregnancies with Down syndrome will be revealed by a triple test. Refinements have taken place, with “free beta” (part of the hCG molecule) replacing hCG itself, and with the addition of PAPP-A replacing estriol, increasing the sensitivity and specificity of the test. Further gains in sensitivity and specificity comes from adding an ultrasound test for nuchal translucency. Even so, false positive tests are possible, which will be resolved only by performing CVS or amniocentesis, and so also are false negative tests, which means that CVS and amniocentesis should still be considered in otherwise high-risk situations.

triple-X syndrome A trisomy with a karyotype of 47,XXX -- a female with an extra X-chromosome. The old description of “super female” is misleading, because fertility, if affected, is most likely reduced; primary ovarian failure is more common than with a normal chromosome complement and premature menopause then follows.

triploid A state of 69 chromosomes, or three times the haploid number, most commonly caused by fertilization of the egg with two sperm; the embryo that results can develop as far as a fetus, but is doomed to miscarry. The trophoblast of the placenta often undergoes partial changes of a hydatidiform mole. The noun form for this adjective is triploidy (the state of being triploid).

triptorelin A GnRH-agonist marketed by Ipsen Biotech as Decapeptyl.

trisomy An abnormality of the chromosome complement in which there is an extra chromosome seen on the karyotype. The extra chromosome can be an autosome, such as in Down syndrome (trisomy 21), or a sex chromosome, such as triple-X syndrome (47,XXX), Klinefelter syndrome (47,XXY) and extra-Y-chromosome syndrome (47,XYY).

trisomy 21 A trisomy for chromosome number 21, or an extra chromosome-21. This is the most common of the trisomies and gives rise to Down syndrome. Research has shown that the commonest source of the extra chromosome is a mistake in the first division of meiosis in the egg cell (during the many years it rests as a primary oocyte).

trophectoderm Group of cells that differentiates around the periphery of the developing embryo when it is a blastocyst and which will, if all goes well after implantation, form the placenta and membranes. See also inner cell mass and trophoblast.

trophoblast As the cells of the early embryo specialize, they soon differentiate into: (1) central ones that will form the embryo or fetus itself; and (2) peripheral ones (the trophoblast) that will be responsible for invading the mother’s tissues (see implantation) and will form the placenta and the membranes. See also cytotrophoblast, syncytiotrophoblast and extravillous trophoblast.

true hermaphrodism Intersex when tissue typical of an ovary and a testis is found in the one person. The genital organs can appear to be normal female, normal male, or somewhere in between. Intersex states where there are either normal ovaries or normal testes (but not both) are sometimes called pseudohermaphrodism.

truth A self-evident ethical principle, which has value provided no substantial harm is done; not to be dispensed with for expediency alone.

tubal abortion A tubal ectopic pregnancy that is in the process of being expelled out the fimbrial end of the fallopian tube.

tubal anastomosis Microsurgery of the fallopian tubes in which an area of blockage is cut out and the healthy bits of tube on each side of the blockage are sewn back together. Can be done for localised salpingitis, including salpingitis isthmica nodosa, and for sterilization reversal. The operation is described in WebPage 13.

tubal canalization Overcoming a localized obstruction of the isthmus or the interstitial segment of the fallopian tube by pushing a wire or a catheter through it, enabling (in some cases) the tube to be “re-canalized” and so to remain open after being blocked before; it’s an attractive alternative to tubal anastomosis and can be performed either during the investigation of tubal infertility with hysteroscopy, laparoscopy and falloposcopy or at the time of carrying out a hysterosalpingogram (see selective salpingography. Because not all tubes that seem to be blocked are in fact blocked (sometimes a normal tube will not allow fluid to pass through it for hormonal reasons or because of a spasm), care needs to be taken to investigate the tube properly before canalization is undertaken.

tubal embryo-stage transfer (TEST) A variation of zygote intrafallopian transfer (ZIFT) in which, usually a day after when ZIFT (or PROST) would be carried out, cleaving embryos (at a two-cell to four-cell stage) are transferred to the fallopian tube as part of an in vitro fertilization program.

tubal ligation A sterilization operation in a woman involving interruption of the fallopian tubes.

tubal patency See tests for tubal patency.

tubal pregnancy An ectopic pregnancy located in the fallopian tube; most occur in the ampulla, but others can be located in the narrower isthmus or in the interstitial segment (see interstitial pregnancy).

tubule For those of the testis, see testicular tubules.

Turner syndrome The combination of primary ovarian failure with constitutional (that is, genetically determined) shortness; often with other clinical abnormalities, including “webbing” of the neck; an increased “carrying angle” at the elbow; short fourth metatarsal (feet) and metacarpal (hand) bones (the bone within the hand that leads to the ring finger), and sometimes abnormalities of the heart and the thyroid gland. Associated with a karyotype that is 45,X (a monosomy, with one u missing) or with partial loss (‘deletion’) of one of a pair of X-chromosomes. The single X-chromosome present can come from the mother or the father -- and, interestingly, it behaves differently: if it comes from the mother the girl is likely to be rather socially disruptive (the way little boys typically are), whereas if the X-chromosome comes from the father her behavior tends to be closer to normal for that of a girl!

 

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ultrashort protocol A variation of the short protocol for using GnRH-agonists with injections of follicle stimulating hormone (FSH) for controlled induction of superovulation in assisted conception programs. The GnRH-agonist is started with menstruation, a day or two before the injections of FSH start, and is discontinued after about 5 days from starting it (i.e. often a week or more before ovulation). There are no special advantages, whereas there’s a potential disadvantage: a much more thorough suppression of the woman’s own u (and maybe FSH) than if the GnRH-agonist is continued -- potentially causing stimulated follicles to “run out of puff” before they are fully mature. The details are in the box, The long, short and ultrashort of GnRH-agonists, in WebPage 20. The ultrashort protocol should not be used with pure forms of FSH, such as Fertinex, Gonal-F, Metrodin HP or Puregon, or poor egg quality will result if some luteinizing hormone is not administered.

ultrasound An imaging procedure like radar, but using high frequency sound waves; used for diagnosis (and, by physical therapists, in a different energy band, for treatment). See also transvaginal ultrasound.

unexplained infertility Infertility for which no obvious cause has been found after the following tests have been done with normal results: a sperm count or postcoital test; a test of ovulation, such as a serum progesterone that is satisfactorily high; and a laparoscopy (used to show that the tubes are open and that there is no endometriosis or other obvious abnormality). Although a hysterosalpingogram (HSG) can substitute for laparoscopy in excluding blockage of the fallopian tubes, an HSG can miss peritubal adhesions and will miss endometriosis. Infertility should not be considered unexplained unless a thorough, careful laparoscopy has been done.

unicornuate uterus A uterine anomaly that comes about when the uterus forms (in the embryo) from just one Müllerian duct; the uterus will be a little smaller than normal (making a miscarriage or premature labor more likely), and will be connected by a fallopian tube to just one ovary, contributing slightly to infertility (since, on average, only half of ovulations have a chance of resulting in pregnancy -- see the box, One ovary can be okay … , in WebPage 13). Reproduction, however, can be normal, and a woman might go through life with a unicornuate uterus and not know it. Diagnosed by hysteroscopy and laparoscopy, by hysterosalpingogram or -- particularly effectively -- by three-dimensional ultrasound. There is more abut this anomaly, including a diagram, in WebPage 18. Often there is a simultaneous abnormality of the kidneys, such as one kidney instead of two, diagnosable by abdominal ultrasound or, more specifically, by a special kidney x-ray study called an intravenous pyelogram.

urinary LH-kit A home test for ovulation in which the urine is tested for luteinizing hormone. If the urine shows a positive test, ovulation will usually take place within 24 to 36 hours. Electronic devices that perform the same function are available (and are increasingly popular in the U.K.). For more on making the most of your natural chances of getting pregnant, read WebPage 19.

urofollitropin Generic name for FSH derived from the urine of menopausal women sources. See urinary menopausal gonadotropin, Fertinex, Humegon, Menogon and Metrodin. FSH of recombinant (synthetic) origin is called follitropin.

uterine anomaly Abnormality of the shape of the uterus a woman is born with (it is congenital); some uterine anomalies tend to cause recurrent miscarriages, premature labor or breech births; discussed in WebPage 18.

uterine curettage See curettage and vacuum curettage.

uterine septum A septum or wall separating the cavity of the u into two halves; a cause of recurrent miscarriages.

uterus The womb, in which pregnancy is gestated from the time of implantation of the embryo until delivery or miscarriage; formed from the joining of the two Müllerian ducts (in the absence of anti-Müllerian hormone); composed of the main, upper part (the uterine fundus) and a lower neck, or cervix, which connects it to the upper part of the vagina; most of its wall is made of muscle tissue (the myometrium), but with an inner lining of glands (the endometrium) and, on the outer surface, a thin covering of uterine serosa. Best seen on transvaginal ultrasound, especially a three-dimensional ultrasound; its cavity is best displayed with a hysterosalpingogram (or, strictly, a hysterogram).

utilitarian ethics A set of ethical beliefs based on maximizing good for the greatest number of people. For modern purposes, similar to teleological ethics (i.e. consequential considerations) but with a community-wide reference instead of a context of individual priority. Nowadays concerned with the equitable and consistent distribution of restricted public resources. Open to change according to the systematic assessment of outcomes (and hence “evidence based”). For practical application, and a contrast to deontological ethics and teleological ethics, read the box, Ethics: moral imperatives, outcomes and equity, in WebPage 26. Refer also to evidence based ethics.