Welcome to the glossary part of our IVFWales site. Here we have included a list of all the terms used in the site or that you may hear in clinic. Each term has an accompanying definition or explanation.
Abortion, Threatened:
Spotting or bleeding that occurs early in the pregnancy. May progress to spontaneous abortion.
Adhesion:
Scar tissue occurring in the abdominal cavity, fallopian tubes, or inside the uterus. Adhesions can interfere with transport of the egg and implantation of the embryo in the uterus.
AID (Artificial Insemination Donor):
See Intrauterine Insemination Donor.
AIH (Artificial Insemination Homologous):
See Intrauterine Insemination.
Amenorrhea:
Refers to a woman who has never had a period.
Amenorrhea, Secondary:
A term describing a woman who has menstruated at one time, but who has not had a period for six months or more.
Androgens:
Male sex hormones.
Andrologist:
A scientist who performs laboratory evaluations of male fertility. Usually affiliated with a fertility treatment centre working on in vitro fertilization.
Anovulation:
The failure to ovulate; ovulatory failure.
Antibodies:
Chemicals made by the body to fight or attack foreign substances entering the body. Normally they prevent infection; however, when they attack the sperm or fetus, they cause infertility. Sperm antibodies may be made by either the man or the woman.
Antisperm Antibodies:
Antibodies are produced by the immune system to fight off foreign substances,like bacteria. Antisperm antibodies attach themselves to sperm and inhibit movement and their ability to fertilize.
Artificial Insemination (AI):
The depositing of sperm in the vagina near the cervix or directly into the uterus, with the use of a syringe instead of by coitus. This technique is used to overcome sexual performance problems, to circumvent sperm-mucus interaction problems, to maximize the potential for poor semen, and for using donor sperm. See also Intrauterine Insemination and Intrauterine Insemination Donor
Artificial Insemination Donor (AID):
Artificial insemination with donor sperm. A fresh donor semen specimen or a thawed frozen specimen is injected next to the woman's cervix. See DIUI
Artificial Insemination:
Artificial insemination with the husband's sperm. The sperm may be washed and injected directly into the wife's uterus. Often used with poor semen or to overcome sperm-mucus problems.
Asherman's Syndrome:
A condition where the uterine walls adhere to one another. Usually caused by uterine inflammation.
Assisted Hatching:
An in vitro procedure in which the zona pellucida of an embryo (usually at eight-cell stage) is perforated by chemical, mechanical, or laser-assisted methods to assist separation of the blastocyst from the zona pellucida.
Assisted Reproductive Technology (ART):
Several procedures employed to bring about conception without sexual intercourse, including IUI, IVF, ICSI.
Asthenozoospermia:
Low sperm motility.
Azoospermia:
Semen containing no sperm, either because the testicles cannot make sperm or because of blockage in the reproductive tract.
Beta hCG Test:
A blood test used to detect very early pregnancies and to evaluate embryonic development.
Bicornuate Uterus:
A congenital malformation of the uterus where the upper portion (horn) is duplicated.
Biochemical Pregnancy:
Evidence of conception based only on biochemical data in serum or urine before ultrasound evidence of a gestational sac.
Birth Defect:
Structural, functional or developmental abnormalities present at birth or later in life, due to genetic or nongenetic factors acting before birth.
Blastocyst:
An embryo with a fluid-filled blastocele cavity (usually developing by five or six days after fertilization).
Cancelled Cycle:
An ART cycle in which ovarian stimulation or monitoring has been carried out with the intent of undergoing ART but which did not proceed to follicular aspiration or, in the case of a thawed embryo, to transfer.
Capacitation:
A process that sperm undergo as they travel through the woman's reproductive tract. Capacitation enables the sperm to penetrate the egg.
Cervical Mucus:
A viscous fluid plugging the opening of the cervix. Most of the time this thick mucus plug prevents sperm and bacteria from entering the womb. However, at midcycle, under the influence of estrogen, the mucus becomes thin, watery, and stringy to allow sperm to pass into the womb. See also Cervix
Cervical Smear:
A sample of the cervical mucus examined microscopically to assess the presence of estrogen (ferning) and white blood cells, indicating possible infection.
Cervix:
The opening between the uterus and the vagina. The cervical mucus plugs the cervical canal and normally prevents foreign materials from entering the reproductive tract. The cervix remains closed during pregnancy and dilates during labor and delivery to allow the baby to be born.
Chocolate Cyst:
A cyst in the ovary that is filled with old blood; endometrioma. Occurring when endometriosis invades an ovary, it causes the ovary to swell. Frequently, patients with large endometriomas do not have any symptoms. If the cyst ruptures or the ovary containing the cyst twists, emergency surgery may be necessary. Usually treatment can be carried out through the laparoscope.
Chromosome:
The structures in the cell that carry the genetic material (genes); the genetic messengers of inheritance. The human has forty-six chromosomes, twenty-three coming from the egg and twenty-three coming from the sperm.
Clinical Pregnancy:
Evidence of pregnancy by clinical or ultrasound parameters (ultrasound visualization of a gestational sac). It includes ectopic pregnancy. Multiple gestational sacs in one patient are counted as one clinical pregnancy.
Conceptus:
The early products of conception; the embryo and placenta.
Cone Biopsy:
A surgical procedure used to remove precancerous cells from the cervix. The procedure may damage the cervix and thus disrupt normal mucus production or cause an incompetent cervix, which may open prematurely during pregnancy.
Contraception:
A congenital condition characterized by elevated androgens which suppress the pituitary gland and interfere with spermatogenesis or ovulation. Women may have ambiguous genitalia from the excess production of male hormone.
Contraceptive, Oral:
A medication that prevents ovulation and pregnancy. Up to 3 percent of women taking the Pill will become anovulatory when they stop taking it. The regulatory effects of the Pill can also disguise symptoms of fertility problems-- for example, an irregular cycle or endometriosis. May be used to control the symptoms and development of endometriosis.
Controlled Ovarian Hyperstimulation (COH):
Medical treatment to induce the development of multiple ovarian follicles to obtain multiple oocytes at follicular aspiration.
Corpus Luteum:
The yellow-pigmented glandular structure that forms from the ovarian follicle following ovulation. The gland produces progesterone, which is responsible for preparing and supporting the uterine lining for implantation. Progesterone also causes the half-degree basal temperature elevation noted at midcycle during an ovulatory cycle. If the corpus luteum functions poorly, the uterine lining may not support a pregnancy. If the egg is fertilized, a corpus luteum of pregnancy forms to maintain the endometrial bed and support the implanted embryo. Picture of a corpus luteum. A deficiency in the amount of progesterone produced (or the length of time it is produced) by the corpus luteum can mean the endometrium is unable to sustain a pregnancy. This is called Luteal Phase Defect (LPD).
Cryopreservation:
The freezing and storage of gametes, zygotes, or embryos.
DIUI (Donor Intrauterine Insemination):
Artificial insemination with donor sperm. A fresh donor semen specimen or a thawed frozen specimen is injected next to the woman's cervix. See DIUI
Dysmenorrhea:
Painful menstruation. This may be a sign of endometriosis.
Dyspareunia:
Painful intercourse for either the man or the woman.
Ectopic Pregnancy:
A pregnancy outside of the uterus, usually in the fallopian tube. Such a pregnancy can rarely be sustained, and often leads to decreased or complete loss of function in the affected tube. Methotrexate is now used to dissolve the pregnancy without causing major damage to the tube.
Egg Retrieval:
A procedure used to obtain eggs from ovarian follicles for use in in vitro fertilization. The procedure may be performed during laparoscopy or by using a long needle and ultrasound to locate the follicle in the ovary.
Ejaculate:
The semen and sperm expelled during ejaculation.
Ejaculation:
The physiological process by which the semen is propelled from the testicles, through the reproductive tract, and out the opening of the penis.
Embryo:
The early products of conception; the undifferentiated beginnings of a baby; the conceptus.
Embryo Donation:
The transfer of an embryo resulting from gametes that did not originate from the recipient or her partner.
Embryo Transfer
Placing an egg fertilized outside the womb into a woman's uterus or fallopian tube.
Embryo Transfer Cycle
An ART cycle in which one or more embryos are transfered into the uterus or fallopian tube.
Endometrium:
The lining of the uterus which grows and sheds in response to estrogen and progesterone stimulation; the bed of tissue designed to nourish the implanted embryo.
Epididymis:
A coiled, tubular organ attached to and lying on the testicle. Within this organ the developing sperm complete their maturation and develop their powerful swimming capabilities. The matured sperm leave the epididymis through the vas deferens.
Fallopian Tubes:
Ducts through which eggs travel to the uterus once released from the follicle. Sperm normally meet the egg in the fallopian tube, the site at which fertilization usually occurs.
Fertility doctor:
A physician specializing in the practice of fertility. .
Fertility Treatment:
Any method or procedure used to enhance fertility or increase the likelihood of pregnancy, such as ovulation induction treatment, varicocoele repair, and microsurgery to repair damaged fallopian tubes. The goal of fertility treatment is to help couples have a child.
Fertility tests:
The initial medical examinations and tests performed to diagnose or narrow down the cause of fertility problems.
Fertilization:
The combining of the genetic material carried by sperm and egg to create an embryo. Normally occurs inside the fallopian tube (in vivo) but may also occur in a petri dish (in vitro). See also In Vitro Fertilization.
Foetus:
A term used to refer to a baby during the period of gestation between eight weeks and term.
Fibroid (Myoma or Leiomyoma):
A benign tumor of the uterine muscle and connective tissue.
Fimbria:
The opening of the fallopian tube near the ovary. When stimulated by the follicular fluid released during ovulation, the fingerlike ends grasp the ovary and coax the egg into the tube.
Follicles:
Fluid-filled sacs in the ovary which contain the eggs released at ovulation.
Each month an egg develops inside the ovary in a fluid-filled pocket called a follicle. This follicle is one inch in size and is about ready to ovulate.
Follicular Fluid:
The fluid inside the follicle that cushions and nourishes the ovum. When released during ovulation, the fluid stimulates the fimbria to grasp the ovary and coax the egg into the fallopian tube.
Follicle Stimulating Hormone (FSH):
A pituitary hormone that stimulates spermatogenesis and follicular development. In the man FSH stimulates the Sertoli cells in the testicles and supports sperm production. In the woman FSH stimulates the growth of the ovarian follicle. Elevated FSH levels are indicative of gonadal failure in both men and woman.
Follicular Phase:
The pre-ovulatory portion of a woman's cycle during which a follicle grows and high levels of estrogen cause the lining of the uterus to proliferate. Normally takes between 12 and 14 days.
Full-term Birth:
A birth that takes place at 37 or more completed weeks of gestational age. This includes both live births and stillbirths.
Gamete:
A reproductive cell:Sperm in men, the egg in women.
Germ Cell:
In the male the testicular cell that divides to produce the immature sperm cells; in the woman the ovarian cell that divides to form the egg (ovum). The male germ cell remains intact throughout the man's reproductive life; the woman uses up her germ cells at the rate of about one thousand per menstrual cycle, although usually only one egg matures each cycle.
Germ Cell Aplasia (Sertoli Cell Only):
An inherited condition in which the testicles have no germ cells. Since men with this condition have normal Leydig cells, they will develop secondary sex characteristics. May also be caused by large and/or prolonged exposure to toxins or radiation.
Gestational Sac:
A fluid-filled structure containing an embryo that develops early in pregnancy usually within the uterus.
Gonadotrophins:
Hormones which control reproductive function: Follicle Stimulating Hormone and Lutenizing Hormone.
Gonadotrophin Releasing Hormone (GnRH):
A substance secreted by the hypothalamus every ninety minutes or so. This hormone enables the pituitary to secrete LH and FSH, which stimulate the gonads. See also FSH; LH.
Gonad:
The gland that makes reproductive cells and "sex" hormones, as the testicles, which make sperm and testosterone, and the ovaries, which make eggs (ova) and estrogen.
Gonorrhea:
An infection that is usually asymptomatic, but that may cause a bad-smelling yellowish vaginal discharge and red and swollen vaginal walls. If it reaches the fallopian tubes, the woman will suffer pain, develop a high fever, and possibly develop tubal blockage. The responsible organism may also impair sperm and prevent pregnancy. In the man gonorrhea seldom leads to damage, but it may cause a painful infection.
Hirsutism:
The overabundance of body hair, such as a mustache or pubic hair growing upward toward the navel, found in women with excess androgens.
Hostile Mucus:
Cervical mucus that impedes the natural progress of sperm through the cervical canal.
Human Chorionic Gonadotrophin (HCG):
The hormone produced in early pregnancy which keeps the corpus luteum producing progesterone. Also used via injection to trigger ovulation after some fertility treatments, and used in men to stimulate testosterone production.
Human Menopausal Gonadotropin (HMG):
A combination of hormones FSH and LH, which is extracted from the urine of post-menopausal women. Used to induce ovulation in several fertility treatments.
Hyperstimulation (Ovarian Hyperstimulation Syndrome, OHSS):
A potentially life-threatening side effect of Pergonal ovulation induction treatment. Arises when too many follicles develop and hCG is given to release the eggs. May be prevented by withholding the hCG injection when ultrasound monitoring indicates that too many follicles have matured.
Hypospermatogenesis:
Low sperm production.
Hysterosalpingogram (HSG):
An x-ray of the pelvic organs in which a radio-opaque dye is injected through the cervix into the uterus and fallopian tubes. This test checks for malformations of the uterus and blockage of the fallopian tubes.
Hysteroscopy:
A procedure in which the doctor checks for uterine abnormalities by inserting a fiber-optic device. Minor surgical repairs can be executed during the procedure.
IAIH (Intrauterine Artificial Insemination Husband):
Artificial insemination where the husband's sperm is injected directly into the uterus to avoid cervical mucus problems or to maximize the potential for poor semen. See also Artificial Insemination.
ICSI:
See also Intracytoplasmic Sperm Injection
Immature Sperm (Germinal Cell):
A sperm that has not matured and gained the ability to swim. In the presence of illness or infection such sperm may appear in the semen in large numbers.
Implantation (Embryo):
The embedding of the embryo into tissue so it can establish contact with the mother's blood supply for nourishment. Implantation usually occurs in the lining of the uterus; however, in an ectopic pregnancy it may occur elsewhere in the body.
Impotence:
The inability of the man to have an erection and to ejaculate.
Incompetent Cervix:
See Cervix, Incompetent
Initiated Cycles:
ART treatment cycles in which the woman receives ovarian stimulation or monitoring, in the case of spontaneous cycles, irrespective of whether or not follicular aspiration was attempted.
Intracytoplasmic Sperm Injection (ICSI):
A micromanipulation procedure where a single sperm is injected into the egg to enable fertilization with very low sperm counts or with non-motile sperm.
In Vitro Fertilization (IVF):
Literally means "in glass." Fertilization takes place outside the body in a small dish.
Infertility:
The inability to conceive after a year of unprotected intercourse or the inability to carry a pregnancy to term.
IUD (Intrauterine Device):
A device placed into the uterus to prevent pregnancy. IUD insertion has been associated with an increased incidence of infection, which may damage the fallopian tubes, and is therefore not recommended for women with multiple sexual partners.
Intrauterine Insemination (IUI):
The depositing of sperm in the vagina near the cervix or directly into the uterus, with the use of a syringe instead of by coitus. This technique is used to overcome sexual performance problems, to circumvent sperm-mucus interaction problems, to maximize the potential for poor semen, and for using donor sperm. See also Intrauterine Insemination Donor
Karyotyping:
A test performed to analyze chromosomes for the presence of genetic defects.
Klinefelter's Syndrome:
A genetic abnormality characterized by having one Y (male) and two X (female) chromosomes. May cause a fertility problem.
Laparoscope:
A small telescope that can be inserted into a hole in the abdominal wall for viewing the internal organs; the instrument used to perform a laparoscopy. Used to diagnose and treat a number of fertility problems including endometriosis, abdominal adhesions, and polycystic ovaries. Also used in egg retrieval for in vitro fertilization.
Laparoscopy:
Examination of the pelvic region by using a small telescope called a laparoscope.
Laparotomy:
Major abdominal surgery where reproductive organ abnormalities can be corrected and fertility restored, such as tubal repairs and the removal of adhesions.
Leiomyomata:
See Fibroid.
Leydig Cell:
The testicular cell that produces the male hormone testosterone. The Leydig cell is stimulated by LH from the pituitary gland.
Live Birth:
A birth in which a fetus is delivered with signs of life after complete expulsion or extraction from its mother, beyond 20 completed weeks of gestational age. Live births are counted as birth events (e.g., a twin or triplet live birth is counted as one birth event).
Live Birth Delivery Rate:
The number of live birth deliveries expressed per 100 initiated cycles, aspiration cycles, or embryo transfer cycles. When delivery rates are given, the denominator (initiated, aspirated, or embryo transfer cycles) must be specified. It includes deliveries that resulted in at least one live birth. Note: The delivery of a singleton, twin, or other multiple birth is registered as one delivery.
Luteal Phase:
Post-ovulatory phase of a woman's cycle. The corpus luteum produces progesterone, which causes the uterine lining to thicken to support the implantation and growth of the embryo.
Luteal Phase Defect (or deficiency) (LPD):
A condition that occurs when the uterine lining does not develop adequately because of inadequate progesterone stimulation; or because of the inability of the uterine lining to respond to progesterone stimulation. LPD may prevent embryonic implantation or cause an early abortion.
Luteinized Unruptured Follicle (LUF) Syndrome:
A condition in which the follicle develops and changes into the corpus luteum without releasing the egg.
Luteinizing Hormone (LH): Pituitary hormone that stimulates the gonads. In the man LH is necessary for spermatogenesis (Sertoli cell function) and for the production of testosterone (Leydig cell function). In the woman LH is necessary for the production of estrogen. When estrogen reaches a critical peak, the pituitary releases a surge of LH (the LH spike), which releases the egg from the follicle.
Luteinizing Hormone Surge (LH SURGE):
The release of luteinizing hormone (LH) that causes release of a mature egg from the follicle. Ovulation test kits detect the sudden increase of LH, signaling that ovulation is about to occur (usually within 24-36 hours).
Malformation Rate:
Includes all structural, functional, genetic and chromosomal abnormalities identified in aborted tissue or diagnosed before or after birth.
Masturbation:
A method used to collect semen for analysis and for artificial insemination; manual stimulation of the penis leading to ejaculation.
Maturation Arrest:
A testicular condition in which at one stage of sperm production all sperm development halts throughout all testicular tubules. May result in oligospermia or azoospermia.
Meiosis:
The cell division, peculiar to reproductive cells, which allows genetic material to divide in half. Each new cell will contain twenty-three chromosomes. The spermatids (immature sperm) and ova (eggs) each contain twenty-three chromosomes, so when they combine (fertilize), the baby will have a normal complement of forty-six.
Menorrhagia:
Heavy or prolonged menstrual flow.
Menstruation:
The cyclical shedding of the uterine lining in response to stimulation from estrogen and progesterone.
Metrorrhagia:
Menstrual spotting during the middle of the cycle.
Micromanipulation (also referred to as assisted fertilization):
The use of special micromanipulative technology that allows operative procedures to be performed on the oocyte, sperm, or embryo.
Microsurgical Epididymal Sperm Aspiration (MESA):
A procedure in which spermatozoa are obtained from the epididymis by either aspiration or surgical excision.
Miscarriage:
Spontaneous loss of an embryo or fetus from the womb.
Mitosis:
The division of a cell into two identical cells in which all forty-six human chromosomes are duplicated; the first division of the germ cell.
Myomectomy:
Surgery performed to remove fibroid tumors.
Neonatal Death:
A death within 28 days of birth.
Oestradiol:
The female hormone produced in the ovary. Responsible for formation of the female secondary sex characteristics such as large breasts; supports the growth of the follicle and the development of the uterine lining. At midcycle the peak estrogen level triggers the release of the LH spike from the pituitary gland. The LH spike is necessary for the release of the ovum from the follicle. Fat cells in both obese men and women can also manufacture estrogen from androgens and interfere with fertility.
Oestrogen:
Female sex hormone.
OHSS (Ovarian Hyperstimulation Syndrome):
A potentially life-threatening side effect of ovulation ovulation induction treatment. Arises when too many follicles develop and hCG is given to release the eggs. May be prevented by withholding the hCG injection when ultrasound monitoring indicates that too many follicles have matured.
Oligomenorrhea:
Infrequent menstrual periods.
Oligospermia, Oligozoospermia:
A sperm count below 20 million; a low sperm count; a sperm count low enough to cause a fertility problem.
Oocyte Donation:
An ART procedure performed with third-party oocytes.
Ovarian Cyst:
A fluid-filled sac inside the ovary. An ovarian cyst may be found in conjunction with ovulation disorders, tumors of the ovary, and endometriosis. See also Chocolate Cyst.
Ovarian Failure:
The failure of the ovary to respond to FSH stimulation from the pituitary because of damage to or malformation of the ovary. Diagnosed by elevated FSH in the blood.
Ovulation:
The release of the egg (ovum) from the ovarian follicle.
Ovulation Induction:
Medical treatment performed to initiate ovulation.
Ovulatory Failure (Anovulation):
The failure to ovulate.
Ovum:
The egg; the reproductive cell from the ovary; the female gamete; the sex cell that contains the woman's genetic information.
Patent:
The condition of being open, as with tubes that form part of the reproductive organs.
Pelvic Inflammatory Disease (PID):
An infection of the pelvic organs that causes severe illness, high fever, and extreme pain. PID may lead to tubal blockage and pelvic adhesions.
Placenta:
The embryonic tissue that invades the uterine wall and provides a mechanism for exchanging the baby's waste products for the mother's nutrients and oxygen. The baby is connected to the placenta by the umbilical cord.
Polar Body:
The discarded genetic material resulting from female germ cell division. See also Meiosis.
Polycystic Ovaries (PCO or "Stein-Leventhal Syndrome"):
A condition found in women who don't ovulate, characterized by excessive production of androgens (male sex hormones) and the presence of cysts in the ovaries. Though PCO can be without symptoms, some include excessive weight gain, acne and excessive hair growth.
Preimplantation Genetic Diagnosis (PGD):
Screening of cells from preimplantation embryos for the detection of genetic and/or chromosomal disorders before embryo transfer.
Preterm Birth:
A birth that takes place after at least 20, but less than 37, completed weeks of gestation. This includes both live births and stillbirths. Births are counted as birth events (e.g., a twin or triplet live birth is counted as one birth event).
Premature Ovarian Failure:
A condition where the ovary runs out of follicles before the normal age associated with menopause.
Progesterone:
The hormone produced by the corpus luteum during the second half of a woman's cycle. It thickens the lining of the uterus to prepare it to accept implantation of a fertilized egg.
Prostate Gland:
A gland in the male reproductive system that produces a portion of the semen including a chemical that liquefies the coagulated semen twenty minutes to go one hour after entering the vagina.
Recipient:
In an ART cycle, refers to the woman who receives an oocyte or an embryo from another woman.
Resistant Ovary:
An ovary that cannot respond to the follicle-stimulating message sent by FSH. Primitive germ cells will be present in the ovary; however, they will not respond to FSH stimulation.
Retrograde Ejaculation:
A male fertility problem that allows the sperm to travel into the bladder instead of out the opening of the penis due to a failure in the sphincter muscle at the base of the bladder.
Salpingectomy:
Surgical removal of the fallopian tube.
Salpingolysis:
Surgery performed to remove adhesions that restrict the movement and function of reproductive organs.
Salpingostomy/Fimbrioplasty:
Surgical repair made to the fallopian tubes; a procedure used to open the fimbria.
Scrotum:
The bag of skin and thin muscle surrounding the man's testicles.
Secondary Infertility:
The inability of a couple which has successfully achieved pregnancy to achieve another. This strict medical definition includes couples for whom the pregnancy did not go to term. The common vernacular, however, refers to a couple which has one biological child but is unable to conceive another.
Semen:
The fluid portion of the ejaculate consisting of secretions from the seminal vesicles, prostate gland, and several other glands in the male reproductive tract. The semen provides nourishment and protection for the sperm and a medium in which the sperm can travel to the woman's vagina. Semen may also refer to the entire ejaculate, including the sperm.
Semen Analysis:
A laboratory test used to assess semen quality: sperm quantity, concentration, morphology (form), and motility. In addition, it measures semen (fluid) volume and whether or not white blood cells are present, indicating an infection.
Semen Viscosity:
The liquid flow or consistency of the semen.
Seminal Vesicles:
Glands in the male reproductive system which produce much of the semen volume, including fructose (sugar) for nourishing the sperm and a chemical that causes the semen to coagulate on entering the vagina.
Seminiferous Tubes:
The testicular tubules in which the sperm mature and move toward the epididymis.
Septate uterus:
A uterus divided into right and left halves by a wall of tissue (septum). Women with a septate uterus have an increased chance of early pregnancy loss.
Sertoli (Nurse) Cell:
A testicular cell responsible for nurturing the spermatids (immature sperm). Secretes inhibin, a feedback hormone, which regulates FSH production by the pituitary gland. When stimulated by FSH, the Sertoli cell initiates spermatogenesis.
Short Luted Phase:
A condition in which the corpus luteum deteriorates prematurely, causing the menstrual period to begin approximately ten days (instead of fourteen) after ovulation. Frequently found with women undergoing ovulation induction treatment.
Sperm:
The microscopic cell that carries the male's genetic information to the female's egg; the male reproductive cell; the male gamete.
Sperm Agglutination:
Sperm clumping caused by antibody reactions or by infection.
Sperm Antibodies:
Antibodies that attack and maim sperm. May be formed by either the man against his own sperm or by the woman against her husband's sperm.
Sperm Bank:
A place where sperm are kept frozen in liquid nitrogen for later use in artificial insemination.
Sperm Count:
The number of sperm in ejaculate. Also called sperm concentration and given as the number of sperm per milliliter.
Sperm Maturation:
A process during which the sperm grow and gain their ability to swim. Sperm take about ninety days to reach maturity.
Sperm Morphology:
A semen analysis factor that indicates the number or percentage of sperm in the sample that appear to have been formed normally. Abnormal morphology includes sperm with kinked, doubled, or coiled tails.
Sperm Motility:
The ability of sperm to swim. Poor motility means the sperm have a difficult time swimming toward their goal---the egg.
Sperm Penetration:
The ability of the sperm to penetrate the egg so it can deposit the genetic material during fertilization.
Spermatogenesis:
Sperm production in the testicles.
Sterility:
An irreversible condition that prevents conception.
Stillbirth:
The death of a fetus between the twentieth week of gestation and birth.
Superovulation:
Stimulation of multiple ovulation with fertility drugs; also known as controlled ovarian hyperstimulation (COH).
Testicular Biopsy:
A minor surgical procedure used to take a small sample of testicular tissue for microscopic examination; a test used to diagnose male fertility problems when no other means is available (this is because the biopsy procedure itself may cause testicular damage).
Testicular Failure, Primary:
A congenital, developmental, or genetic error resulting in a testicular malformation that prevents sperm production.
Testicular Failure, Secondary:
Acquired testicular damage - for example, from drugs, prolonged exposure to toxic substances, or a varicocoele.
Testicular Sperm Aspiration (TESA):
A procedure in which spermatozoa are obtained directly from the testicle by either aspiration or surgical excision of testicular tissue.
Testosterone:
The male hormone responsible for the formation of secondary sex characteristics and for supporting the sex drive. Testosterone is also necessary for spermatogenesis.
Turner's Syndrome:
The most common genetic defect contributing to female fertility problems. The ovaries fail to form and appear as slender threads of atrophic ovarian tissue, referred to as streak ovaries. Karyotyping will reveal that this woman has only one female (X) chromosome instead of two.
Ultrasound:
A test used instead of X rays to visualize the reproductive organs; for example, to monitor follicular development and to examine the tubes and uterus. The instrument works by bouncing sound waves off the organs. A picture displayed on a TV screen shows the internal organs.
Undescended Testicles (Cryptorchidism):
The failure of the testicles to descend from the abdominal cavity into the scrotum by one year of age. If not repaired by age six, may result in permanent fertility loss.
Unicornuate Uterus:
An abnormality in which the uterus is "one sided" and smaller than usual.
Urethra:
The tube that allows urine to pass between the bladder and the outside of the body. In the man this tube also carries semen from the area of the prostate to the outside.
Urologist:
A doctor specializing in the genitourinary tract. Performs surgical sperm retrieval (testicular biopsies).
Uterus:
The hollow, muscular organ that houses and nourishes the fetus during pregnancy.
Vagina:
The canal leading from the cervix to the outside of the woman's body; the birth passage.
Varicocoele:
A dilation of the veins that carry blood out of the scrotum. The resulting swollen vessels surrounding the testicles create a pool of stagnant blood, which elevates the scrotal temperature. A major cause of male infertility.
Vas Deferens:
One of the tubes through which the sperm move from the testicles (epididymis) toward the seminal vesicles and prostate gland. These tubes are severed during a vasectomy performed for birth control.
Vasectomy:
The accidental or elective surgical separation of the vasa deferential a procedure used for birth control.
X Chromosome:
The congenital, developmental, or genetic information in the cell that transmits the information necessary to make a female. All eggs contain one X chromosome, and half of all sperm carry an X chromosome. When two X chromosomes combine, the baby will be a girl. See also Y. Chromosome.
Y Chromosome:
The genetic material that transmits the information necessary to make a male. The Y chromosome can be found in one-half of the man's sperm cells. When an X and a Y chromosome combine, the baby will be a boy. See also X Chromosome.
Zygote:
A fertilized egg which has not yet divided.