Glossary of medical terms
Adhesions: internal scar tissue attachments in fibrous bands to the surfaces of organs and tissues that often result from an injury or infection.
Amenorrhea: a lack of menstruation for at least three months without a pregnancy.
Androgens: sex hormones such as testosterone, which are in much higher levels in men than women; these are steroids and essential for both male and female sexual development.
Andrologist: a medical doctor who specialises in the field of male reproduction.
Anovulation: the absence of ovulation even though bleeding can still happen; other medical terms are oligomenorrhea and amenorrhea.
Anti-D injections: human anti-D immunoglobulin injections given to pregnant women who are RhD negative to prevent the development of antibodies that could affect future pregnancies.
Anti-Mullerian hormone: (AMH): a hormone produced in ovarian follicles, and the amount of AMH produced varies depending on the stage of follicle growth, which allows its use as a marker of ovarian reserve.
Antioxidant: a particle that inhibits the unwanted oxidation process in cells. Oxidation is essential to life, but the process can get out of control and damage structures in cells resulting in oxidative stress. There are many antioxidant substances, including minerals, vitamins, enzymes and hormones.
Antisperm antibody testing: a test to detect the presence of antibodies that cause sperm to clump together and reduce the ability of sperm to fertilise eggs.
Assisted reproductive techniques (ART): a term that refers to methods used to achieve pregnancy by artificial or partially artificial means. A crucial infertility treatment that fertile couples may use genetic or transmittable disease reasons (such as HIV).
Asherman’s syndrome: (AS): this is scar tissue that causes adhesions or fibrosis in the basal layer of the uterine cavity that distorts the womb, and 90% of the time, this follows a dilation and curettage (D&C) procedure on a womb that was recently pregnant. When AS is extreme, the whole uterus can become blocked, and even mild scarring can prevent the womb lining from responding normally to hormones.
Aspermia: the term for no semen in the ejaculate
Assisted hatching: an IVF technique involving a small hole in the zona pellucida (gel-like covering of the egg and embryo) being made to aid the implantation of the embryo in the womb.
Asthenozoospermia: the term for reduced or poor sperm motility.
Atresia: the failure (of follicles) to survive the recruitment process from primordial follicle to the later stages of follicular development; see eggs and follicles.
Azoospermia: the absence of sperm in the seminal fluid.
Basal body temperature (BBT): a person’s lowest (core) body temperature during 24 hours, and the temperature changes indicate significant hormonal shifts in the body.
Beta chorionic gonadotropin (hCG): this is another term for “human chorionic gonadotropin”. It’s used to confirm pregnancy, follow the pregnancy progression, and diagnose possible concerns.
Biochemical pregnancy: see chemical pregnancy.
Blighted ovum (egg): a general term for an “anembryonic pregnancy”, meaning a pregnancy without an embryo. When a fertilised egg develops a placenta and a membrane, but the embryo itself doesn’t grow.
Blocking antibodies: substances produced by the cloaking immune system of pregnant women that prevent the aggressive side of her immune system from viewing the developing embryo as a foreign agent and starting an immune reaction that would lead to a miscarriage.
Body mass index (BMI): a way to calculate a person’s relative size (and to a certain extent their percentage of body fat) by dividing the person’s weight by the square of their height.
Bromocriptine (Parlode): a medication used to lower prolactin levels in cases of hyperprolactinaemia.
Capacitation: the change that sperm cells make as they travel through the woman’s reproductive tract, enabling them to penetrate the egg.
Complete blood count (CBC): a routine blood test that provides a wide range of clinical information, including infection and anaemia.
Cervical mucus: the secretions produced by the cervix of the uterus, and these change through the menstrual cycle, with ‘fertile mucus’ being essential for natural fertility in the days before ovulation.
Chemical pregnancy: a pregnancy indicated by a positive hCG level in the blood; however, the hCG fails to keep rising (as is usual) and doesn’t lead to a clinical pregnancy, with ultrasound unable to confirm the presence of a pregnancy.
Chlamydia: a bacterium usually transmitted by sexual contact and can infect mucous membranes in the body and distort structures to cause pelvic inflammatory disease (PID) and infertility; despite this, Chlamydia infections are often unnoticed!
Clinical pregnancy: clinical confirmation of a pregnancy by the presence of hCG in the blood and an ultrasound examination showing a gestational sac in the uterus (or an examination that confirms an ectopic pregnancy or a miscarriage).
Clomiphene citrate (‘clomid’/’serophene’): a synthetic anti-oestrogen drug given early in the menstrual cycle to stimulate an increase in FSH and LH and induce ovulation.
Corpus luteum: the temporary gland that forms from the dominant follicle that ruptured and released the egg at ovulation; it then produces the hormone progesterone during the second half of the menstrual cycle, and if pregnancy occurs, the corpus luteum persists and produces progesterone for the first 14 weeks of the pregnancy.
Cryopreservation: the freezing of tissue, usually embryos from an IVF cycle at −196 °C, to preserve them for future use.
Danazol: a medication used to treat endometriosis by suppressing the cyclic production of FSH/LH to “calm down” the disease. Its use is limited by its masculinising side effects, and GnRH agonists are now more commonly used.
Dehydroepiandrosterone sulfate (DHEAS): an androgen (male) hormone produced by the adrenal gland in both sexes and used to stimulate hormone production. It’s strongly advised that testing is done to ensure that it will help rather than worsen the chances of pregnancy.
Dilation and curettage (D&C): a surgical procedure that involves a surgical instrument called a curette being inserted into the uterus to remove unwanted tissue.
Donor eggs are eggs used in IVF by one woman, having been provided by another woman.
Donor insemination (DI): also known as TDI (therapeutic donor insemination), artificial insemination (AI), or artificial insemination by donor (AID), is a procedure where sperm are placed into a woman’s vagina or cervix.
Donor sperm: sperm used to fertilise a woman’s eggs that aren’t from her partner but usually come from a commercial sperm bank.
DNA fragmentation: the separation or breaking of DNA strands into pieces has significant consequences for fertility as the DNA needs to hold together for a successful pregnancy.
Ectopic pregnancy: a severe and life-threatening condition that involves implantation and development of an embryo outside the uterus (usually in a Fallopian tube or on an ovary).
Embryo: the technical term used to describe the early stages of fetal growth; it becomes a fetus at week 12!
Embryo transfer: the procedure involving the IVF embryo being placed into the uterus.
Endometriosis: the presence of endometrial tissue (the normal uterine lining) outside the uterus, usually in the fallopian tubes, ovaries and pelvic cavity.
Endometritis: Inflammation of the endometrial lining of the uterus, usually due to an infection.
Endocrine system: the hormonal system that regulates many bodily functions, including mood, reproduction, growth and metabolism.
Endometrial biopsy: removal of a small sample of tissue from the lining of the uterus for detailed examination.
Erythrocyte sedimentation rate (ESR): a blood test measuring the rate that red blood cells sediment in an hour; it’s higher if there’s an infection or inflammation in the body and the ESR is also higher in pregnancy and some other conditions such as anaemia or rheumatoid arthritis.
Estrogens (or oestrogens): the main female sex hormone produced by the ovaries from puberty to menopause. They are steroids that also help control metabolism, inflammation, immune function, the development of sexual characteristics and the ability to withstand illness and injury.
Estradiol level (E-2 level): the principal form of estrogen in reproductive-age women.
Fallopian tubes: the pair of tubes that lead from the uterus to the ovaries that play an important role in transporting the fertilised egg from the ovary to the uterus, and are where eggs are fertilised
Fertilisation: penetration of an egg by a sperm and the fusing of the genetic material that they carry.
Fetus: the developmental stage that follows the embryo stage that lasts from the 12th week of pregnancy to the moment of birth.
Fibroid: (also known as a myoma), this is a non-cancerous smooth-muscle tumour that’s part of (or attached to) the uterus, with a number of different types which are defined according to their structure and position.
Follicle: one of the structures in the ovary, each containing an egg and the largest of these in any given menstrual cycle is called the “dominant follicle” that goes on to release an egg at ovulation.
Follicle-stimulating hormone (FSH): is produced in the anterior pituitary gland that for women stimulates the ovary to recruit follicles each cycle and it also acts to ripen a follicle for ovulation. In men, FSH is involved in sperm production.
Follicular phase: the first phase of the menstrual cycle that starts at the start of the period and ends with ovulation, during which the largest of the follicles develops in readiness for ovulation and the functional lining of the womb grows.
Gamete: a sperm or an egg.
Gamete intra-fallopian tube transfer (GIFT): is a (technique now very rarely used) similar to IVF, except that the sperm and eggs are placed inside a catheter and then transferred inside a woman’s Fallopian tube for fertilisation to take place.
Gonadotrophins: hormones that regulate a person’s normal growth, sexual development and reproductive function by stimulating the gonads (ovaries or testes) to produce eggs or sperm.
Gonadotropin release hormone (GnRH): a hormone released from the hypothalamus that controls the production and release of FSH and LH from the anterior pituitary and these hormones then act directly on the ovaries or testes.
Hirsutism: the excessive growth of facial or body hair in women.
HIV (Human immunodeficiency virus) antibodies: a positive test indicates that the antibody to the virus is present in the blood, but doesn’t necessarily mean that the individual has been exposed to the AIDS virus or that he or she has or will get AIDS. A physician or qualified health professional will need to interpret the test result but even if the person isn’t sick they can still infect others by sharing needles or having unprotected sex.
Hormones: these are chemicals that are released by cells or a gland in one part of the body that affects how cells function in other parts of the body.
Hormonal assay: also known as hormone tests and include FSH (follicle-stimulating hormone), LH (luteinising hormone), DHEAS (dehydroepiandrosterone sulfate), prolactin, anti-Mullerian hormone (AMH), estradiol, testosterone and progesterone.
Human chorionic gonadotropin (hCG): a hormone produced by the placenta when it implants into the womb, it stimulates the corpus luteum to continue functioning beyond its usual fourteen-day life span. It’s used in IVF protocols to trigger ovulation or ensure adequate luteal function and is the basis of most pregnancy tests.
Human menopausal gonadotropin (hMG): a natural drug product extracted from the urine of postmenopausal women that contains both human FSH and LH. The drug is used in the treatment of both male and female infertility, although typically it’s used to stimulate the development of multiple eggs.
Hydrocele testis: an accumulation of fluid around a testicle, which is fairly common (but not usually painful) and is linked to reduced male fertility.
Hydrosalpinx: this is when the Fallopian tubes (salpinges) are grossly swollen and distorted and filled with fluid, which is usually after an infection.
Hyperandrogenism: the production of an excess of androgens (such as testosterone) by the adrenal cortex, the ovaries, or the testes. The term is usually used in relation to women (there are few clinical issues for men) and causes hirsutism and virilism. Hyperandrogenism is often due to either ovarian or adrenal diseases and is a feature of many women with PCOS.
Hyperinsulinemia: higher levels of insulin in the blood than normal in relation to glucose levels in the blood. This condition is associated with hypertension, obesity, dyslipidemia (high cholesterol) and glucose intolerance, which are collectively known as “metabolic syndrome”.
Hyperprolactinaemia: the presence of abnormally high levels of prolactin in the blood and the normal levels are below 500 mIU/L for women and below 450 mIU/L for men. High levels of prolactin prevent the start of a menstrual cycle and will also alter male fertility.
Hypothalamic-pituitary-gonadal axis (HPG): a crucial axis that regulates the body’s reproductive system, with changing hormone levels in one of the glands altering the hormones produced by the other glands. The hypothalamus and pituitary glands are both located in the brain and the gonads are the ovaries in women and the testes in men.
Hystero-contrast sonography (HyCoSy): an ultrasound technique involving the injection of aqueous fluid into the Fallopian tubes to provide a contrast medium to detect structural problems.
Hysterosalpingogram (HSG,hHysterogram): an X-ray procedure involving the introduction of a radio-opaque dye into the uterus through the cervix to show the structures of the uterus and fallopian tubes. It’s usually done in the follicular phase of the cycle to diagnose problems such as Asherman’s syndrome or obstructions in the Fallopian tubes.
Hysteroscopy: a procedure to diagnose and treat abnormalities inside the uterine cavity with a telescope-like device that is inserted into the uterus via the cervix.
ICSI: see intra-cytoplasmic sperm injection.
Idiopathic infertility (unexplained infertility): the term used when no reason can be found to explain the cause of a couple’s infertility.
Implantation: the embedding of the embryo in the endometrial lining of the uterus.
Infertility: generally considered the inability to conceive or carry a pregnancy to term after one year of regular unprotected intercourse.
Inhibin: a protein that suppresses the production of FSH and is produced in the ovaries, pituitary gland and placenta in women and in the testes for men.
Insulin: a hormone that’s produced in the pancreas that has a central role in regulating carbohydrate and fat metabolism in the body by making cells in the muscles, liver and fat tissue absorb glucose (sugar) from the blood. Glucose is stored as glycogen in the liver and muscles and as triglycerides in fat cells. In a normal working system (i.e. not in the case of diabetes mellitus or metabolic syndrome) there’s a constant proportion of insulin in the body to remove excess glucose from the blood, as high levels are toxic.
Insulin resistance: a condition where the body doesn’t respond to normal levels of the hormone insulin. The pancreas produces insulin but the cells in the body become resistant to insulin (through changes in their surface receptors) and are unable to use it effectively and this causes raised insulin levels in the blood.
Intracytoplasmic sperm injection (ICSI): the injection of a single sperm into an egg (using a very sharp glass needle) to fertilise it. This technique of micromanipulation was first used in 1992 and is now used in over half of all IVF cycles, especially when male-factor is part of infertility.
Intrauterine insemination (IUI): also known as “artificial insemination” (AI) and is the insertion of specially prepared sperm directly into the uterus through the cervix using a catheter. The sperm are “washed” and separated to get the best ones and increase the chances of fertilisation and placing the sperm directly into the uterus avoids any mucus issues that could be causing infertility.
In-vitro fertilisation (IVF): the removal of eggs from mature follicles in the ovary and fertilisation by a sperm outside the human body. Embryos are then incubated in the laboratory for a few days before being put inside the woman’s uterus.
In-vitro maturation (IVM): the removal of eggs from immature follicles as well as mature follicles to be ‘matured’ and fertilised sperm outside the human body as in normal IVF.
Laparoscopy: a surgical procedure with the insertion of a telescope-like device through a small incision near the navel to see inside the pelvic cavity and can also include some types of surgery.
Leptin: a hormone that comes from fat (adipose) cells in the body that has an important function in regulating metabolism, appetite and sexual development. Low levels of leptin result in delayed puberty or periods stopping, and high levels can cause the early onset of puberty and PCOS. Leptin wasn’t discovered until 1994 and offers a genetic and hormonal basis for obesity.
Leptin resistance: is similar to the way Type II diabetics are resistant to insulin; high levels of leptin in the long term lead to desensitisation to leptin and this results in no reduction of appetite or increase in metabolism, with an increase in fat stores.
LH surge: the spontaneous release of large amounts of luteinising hormone (LH) which normally leads to the release of a mature egg at ovulation.
Leukocytospermia: the presence of white blood cells in the semen sample.
Leuprolide acetate (Lupron): a drug used in IVF that functions like GnRH and is used to suppress a woman’s secretion of FSH and LH when they might be interfering with her ability to respond appropriately to fertility drugs.
Lupron “Flare” protocol: a form of IVF that takes advantage of the initial rise or “flare” of LH and FSH, which occurs 24 hours after the start of Lupron administration.
Lupron “down-regulation”: a treatment cycle where Lupron is used to suppress a woman’s own production of hormones before she’s stimulated to develop follicles.
Luteal phase: the days of the menstrual cycle following ovulation and end with menstruation which usually lasts 12-to-16-days.
Luteinizing hormone (LH): a hormone that’s produced and released by the anterior pituitary gland that’s involved in follicle development and is responsible for triggering ovulation in women and stimulates testosterone production in men’s testes.
Lymphocyte antibody detection assay (LAD): this measures the reaction levels of antibodies to proteins of non-self blood cells. These antibodies are of interest as they appear to protect the pregnancy and in women, with a history of implantation failures and/or miscarriages LAD levels may be unusually low (IgG B cell levels<30%).
Lymphocyte immunisation therapy (LIT): a procedure involving the injection of white blood cells from the prospective father into the skin of the prospective mother to prepare the mother’s immune system for pregnancy. Since both the mother and father’s DNA form the baby’s genes, LIT is thought to assist the mother’s immune system to develop tolerance to the father’s genetically foreign tissues.
Maternal serum: blood that is taken from the potential mother; it’s sometimes added to the embryo-freezing medium to provide a source of protein.
Menorrhagia: menstrual bleeding that occurs at normal intervals but is prolonged or excessive and is usually taken to be more than 10 days menses and or over 60ml blood loss.
Menometrorrhagia: irregular, non-cyclic bleeding that is prolonged or excessive.
Metrorrhagia: excessive bleeding that occurs at irregular intervals between menstrual cycles.
Metabolic syndrome: a collection of conditions including hyper-insulinemia, obesity, hypertension, high cholesterol and glucose intolerance.
Microadenoma: noncancerous tumours that occur in the pituitary gland.
Micromanipulation: microscopic procedures in fertility treatment include ICSI or assisted hatching with micromanagement of eggs, sperm, or embryos.
Mixed antiglobulin reaction test (MAR test): a test used to diagnose immune-based infertility by showing the level of anti-sperm antibodies present in a sperm sample.
Myoma: a relatively common benign tumour of the muscle of the uterus that’s also known as a fibroid.
Myomectomy: the surgical removal of a myoma (fibroid) from the wall of the uterus.
Oligoasthenoteratozoospermia: a low concentration, motility and number of normally shaped sperm.
Oligozoospermia: an abnormally low number of sperm in a semen sample.
Oligomenorrhoea: menstrual bleeding that occurs in cycles that are greater than 35 days or when there are less than eight bleeds from the vagina in a year.
Oligoovulation: infrequent or irregular ovulation (usually defined as cycles of 36 days or more, or fewer than 8 cycles a year).
Oocyte: the egg cell that’s produced in the ovaries that’s also called the ovum.
Ovarian hyper-stimulation syndrome (OHSS): a complication from some fertility treatments, including Clomid & FSH. Most cases are mild, but in a small proportion, it’s severe with abdominal distension above the waist, lower abdominal pains, shortness of breath, concentrated urine and calf and chest pains.
Ovulation: the release of a mature egg from the ovary.
Ovulation induction: this involves the use of hormone therapy (such as clomiphene citrate) or injectable gonadotropins to stimulate egg development and release.
Oxidative stress (OS): a state of imbalance between the development of “reactive oxygen species” (ROS) such as peroxides and “free radicals”, and the body’s ability to quickly detoxify these chemicals or to repair the damage they cause to proteins, lipids and DNA.
Papanicolaou smear (PAP test): a screening test of the cells of the cervix to see if they’re normal by gently touching the cervix with a cotton swab and a wooden spatula and then examining the cells under a microscope.
Pelvic inflammatory disease (PID): inflammation of the Fallopian tubes, uterus, or ovaries which causes distortion and the formation of scar tissue and adhesions.
Polycystic ovary syndrome (PCOS): a condition characterised by the accumulation of numerous cysts (follicles) on the ovaries and associated with high male hormone levels, anovulation and other metabolic disturbances.
Polymenorrhoea: cycles of menstrual bleeding that are less than 21 days long.
Post-coital test (PCT): the microscopic study of samples of vaginal and cervical secretions taken several hours after sex and examined for live, moving sperm. Incompatibility and mucus issues that may be preventing fertilisation are shown, but it’s now rarely used.
Progesterone (P4): a hormone produced and released by the corpus luteum (in the ovary) during the second half of a cycle and that’s essential for the preparation of the lining of the uterus for implantation. During the later stages of the pregnancy, it’s produced by the placenta and low blood levels indicate supplementation is needed (as in luteal phase defect), or in IVF protocols.
Prolactin: a hormone that’s produced by the anterior pituitary gland and blood levels of prolactin provides information on the hypothalamic-pituitary axis. Treatment options are available when levels are excessively high (hyperprolactinaemia).
Reactive oxygen species (ROS): reactive molecules that contain oxygen and during times of environmental stress, such as heat or toxin exposure, ROS levels can increase dramatically which can lead to significant damage to cell structures.
Rubella test: a blood test that assesses resistance to rubella (German measles) virus. If immunity isn’t present the patient may be advised to have a rubella vaccination and wait three months before attempting pregnancy as active infection causes serious harm to the unborn baby.
Salpingitis: inflammation of the Fallopian tubes, usually due to a bacterial infection.
Secondary infertility: the inability to conceive or carry a pregnancy after a year of having regular, unprotected intercourse having successfully conceived and carried one or more pregnancies previously.
Semen analysis (SA): semen that has been ejaculated within the last hour is assessed under a microscope to count the number of sperm (count), the percentage of moving sperm (motility), and to assess the size and shape of the sperm (morphology).
Sertoli cells: these are ‘nurse’ cells in the seminiferous tubules in the testes that nourish the developing sperm cells through the stages of ‘spermiogenesis’. Sertoli cells develop in the fetus and once the baby boy is born no more are grown.
Sex hormone-binding globulin (SHBG): a type of protein that binds to sex hormones (usually only 1-2% aren’t bound to an SHBG) which limits the availability of sex hormones to cells in the body.
Sexually transmitted infections (STI): infections from bacteria, viruses, fungi and other parasites that are transmitted from one person to another during sexual contact.
Sonohysterogram: the injection of sterile saline into the uterine cavity during an ultrasound examination to increase the accuracy of diagnosis of any irregularities of the cavity (polyps, fibroids, scarring, etc.). It’s also known as a hysterosonogram (HSN) or saline ultrasound.
Sperm antibodies: these are antibodies against sperm cells and can attack and destroy them and both men and women can produce them.
Spermiogenesis: the process by which new sperm cells grow and develop.
Sperm wash: a technique for separating sperm from the seminal fluid that’s used in ART procedures.
Sterility: the total inability to reproduce. Not to be confused with infertility.
Stimulation: the use of hormones to induce the development of multiple mature ovarian follicles rather than the usual one per cycle.
Swim-up test: this technique separates motile sperm from non-motile sperm and cellular debris in a semen sample. The most motile sperm “swim-up” in a small volume of media and are then more easily separated for insemination.
Temperature shift day: the day when the BBT temperature rises at the start of the luteal phase of the cycle.
Teratozoospermia: reduced levels of normally shaped sperm.
Testicles or testes: two male sexual glands contained in the scrotum that produce the male hormone testosterone and the male reproductive cells’ sperm’; see organs and sperm.
Testicular biopsy: the removal of a small sample of testicular tissue, usually to establish the ability of the cells to produce normal sperm.
Testosterone: is the most potent of the male sex hormones that are produced in the testes. Women also produce testosterone, but in much lower quantities.
Ultrasound: the sonar-like technique for visualising the internal organs that are used to count and stage follicles in the ovaries and the assessment of fetus, as well as the diagnosis of a number of other gynaecological issues.
Vaginal ultrasound: an ultrasound probe that’s inserted into the vagina to assess the internal structures: a ‘baseline ultrasound’ shows the ovaries in their un-stimulated state; a ‘follicular ultrasound’ shows egg-follicle maturation and a ‘pregnancy ultrasound’ shows the site of the pregnancy and measures the growth of the fetus.
Varicocoele: this is a collection of varicose veins in the scrotum; there’s a link between varicoceles and reduced fertility where the blood in a varicocele fails to flow normally (it affects 15-20% of men).
Virilism: the development or possession of male secondary sexual characteristics in a female or pre-pubertal male.
Zygote: a technical term for the early stages of the development of an embryo.
Zygote intrafallopian transfer (ZIFT): a historic type of ART where the egg was fertilised in the laboratory and then transferred into the Fallopian tube before it’s started dividing.
17–ketosteroids: substances that form when the body breaks down male steroid sex hormones.
Photo by Romain Vignes on Unsplash
