Glossary of Terms

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A

Adenomyosis

A benign disease that involves the abnormal growth of endometrial tissue (the lining of the uterus) into the uterine wall or myometrium. Can be associated with abnormal bleeding or periods and some data suggest lower pregnancy rates in women with adenomyosis. There is no medical or surgical remedy for adenomyosis.

Adhesions

Scarring is a result of tissue injury. The damage can be caused by infections such as Gonorrhea and Chlamydia, or by previous operations such as removal of cysts or an appendectomy. Endometriosis also causes adhesion formation. Adhesions involving the tubes and/or the ovaries can cause infertility by preventing the normal pick-up of the egg from the surface of the ovary. If adhesions are mild, they can be treated by laparoscopic surgery. If the disease is severe however, surgery will not restore normal fertility. Adhesions inside the uterine cavity are also known as Asherman’s syndrome and may result from prior surgeries of the uterine lining such as polyp or fibroid removal or dilation and curettage procedures. These adhesions can be diagnosed by saline ultrasonography or hysteroscopy and can be removed by hysteroscopy.

Alpha Fetal Protein

A protein secreted by fetal tissue that can be present in the mother's bloodstream. If present in high levels, it can be associated with congenital fetal anomalies such as neural tube defects.

Aneuploidy

An embryo is said to be aneuploidy if it contains an abnormal number of chromosomes. Down Syndrome, or Trisomy 21 is one form of aneuploidy, one of the few chromosome number abnormalities compatible with live birth. Most chromosome aneuploidies result in implantation failure or early miscarriage.

Anti-Mullerian Hormone (AMH)

AMH is a blood test that directly measures ovarian reserve. It is produced directly by early stage ovarian follicles.  High levels (over 1.0) are favorable, while low levels (less than 1.0) indicate decreased ovarian reserve. AMH may be the best measure of the menopausal transition and ovarian age. It may also be useful in predicting ovarian hyperstimulation syndrome, the effects of chemotherapy, and in determining the treatment of PCOS.

AMH seems a superior predictor of ovarian response compared to other markers, including age, and day 3 FSH and estradiol. It offers similar predictive value compared to AFC. AMH can be drawn at any time in the menstrual cycle, and is not affected by hormonal therapy, including oral contraceptives.

Antisperm Antibodies

Antibodies directed against sperm. If directed against the head of the sperm, they can interfere with normal fertilization. 

Antral Follicle Count

An assessment of the number of small follicles present in the ovary at any point in the cycle. This count is ideally between 10-20 follicles and if much lower, can suggest diminished ovarian reserve. See also: Follicle, Diminished Ovarian Reserve.

Arcuate Uterus

A mild deformity of the uterus that involves the presence of a very small separation in the midline of the fundus (the upper part of the uterus) inside the uterine cavity. This condition is usually not associated with infertility or recurrent miscarriages, and therefore rarely needs any form of therapy.

Asherman’s Syndrome

Adhesions inside the uterine cavity are also know as Asherman’s syndrome and may result from prior surgeries of the uterine lining such as polyp or fibroid removal or dilation and curettage procedures. These adhesions can be diagnosed by saline ultrasonography or hysteroscopy and can be removed by hysteroscopy. 

Assisted Hatching

The process of helping an embryo to hatch by making a surgical slit using a specialized laser in the zona pellucida (see Zona pellucida) or "shell." Assisted hatching is performed on Day 3 embryos and frozen-thawed embryos routinely. 

Assisted Reproductive Technologies (ART)

ART is a term for the collective high- technology Infertility treatment procedures such as In Vitro Fertilization, Intracytoplasmic Sperm Injection, Frozen Embryo Transfer, and Testicular Sperm retrieval, that require laboratory handling of sperm and /or eggs.

Azoospermia

The complete absence of sperm. It can result from obstruction of the vas deferens (the duct that carries the sperm from the testicles to the urethra) or from failure of the testes to produce sperm. MESA and TESE are two ART procedures to obtain sperm from azoospermic males.