Fertility Glossary

Explore our glossary to better understand the fertility terms associated with your treatment.

Abortion, Habitual: A pattern of pregnancy loss during which a woman has had three or more miscarriages.

Abortion, Missed: A “miscarriage,” during which the fetus in the uterus is no longer viable but does not expel itself completely from the uterus.

Abortion, Therapeutic: Termination of pregnancy either via medication or instruments.

ACTH: A hormone produced by the pituitary gland to stimulate the adrenal glands

Adhesion: Scar tissue, which can be present anywhere in the body, including 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.

Adrenal Androgens: Male hormones produced by the adrenal gland which, when found in excess, may lead to fertility problems in both genders. A woman with elevated male hormones may form male secondary sex characteristics and suppression of LH and FSH production by the pituitary gland while prolactin may be abnormally high. Elevated levels of androgens may be found in women with polycystic ovaries, or with an adrenal, ovarian or pituitary tumor.

Amenorrhea: The absence of a period.

Androgens: Male sex hormones.

Aneuploidy: A condition in which an abnormal number of chromosomes is found. There may be missing or extra chromosomes present.

Anovulation: A condition in which a woman does not release mature eggs on a regular basis for fertilization. Menses may still occur.

Artificial Insemination: A procedure in which sperm are introduced into a woman’s uterus through clinical means instead of through sexual intercourse to increase the likelihood that sperm will reach and fertilize an egg. Artificial insemination, also called "intrauterine insemination" (IUI).

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 (a protective outer shell) of an embryo is perforated by chemical, mechanical, or laser-assisted methods to assist separation of the blastocyst from the zona pellucida.

Assisted Reproductive Technology (ART): Medical treatments aimed at helping women and couples with fertility issues conceive and give birth. In vitro fertilization, intracytoplasmic sperm injection, pregenetic testing, and assisted hatching are examples of fertility treatments used to help couples begin successful pregnancies.

Azoospermia: The absence of sperm in seminal fluid, usually caused by a blockage or an impairment of sperm production.

Basal Body Temperature: The body temperature upon awakening, before any activity.  A temperature increase (about 0.5oF) may indicate ovulation.

Beta hCG Test (BhCG): A test to determine pregnancy.

Bicornuate uterus:  A congenital malformation of the uterus in which the upper portion (horn) is duplicated.

Blastocyst:  An embryo with a fluid-filled cavity (usually developing by five or six days after fertilization).

Blighted Ovum (egg): A fertilized egg that implants in the uterus, but does not develop further and dies.

Bromocriptine (Parlodel): An oral medication used to lower the level of hormone prolactin when it is abnormally high.

Cervical Mucus: Secretions produced by the cervix. The thickness of the mucus varies according to the phase of the menstrual cycle. In the days just before ovulation, the mucus becomes thin and watery and is easily penetrable by sperm.

Cervical Stenosis: A blockage of the cervical canal from a defect or from complications of surgical procedures.

Cervix: The lower section and opening of the uterus that protrudes into the vagina. Sperm pass through the cervix into the uterus following intercourse.

Cervix, Incompetent: A cervix, which opens prematurely during pregnancy and can cause the loss of the fetus. A cerclage is a procedure in which a stitch or two is put around the cervix to prevent its opening until removed when the pregnancy is to term.

Chromosome: The structures in the cell that carry the genetic material (genes). The human has forty-six chromosomes, twenty-three from the egg and twenty-three from the sperm.

Clomid/Clomiphene Citrate:  An oral fertility drug which stimulates a woman’s ovaries to create one or more eggs.

Cryopreservation: A procedure used to freeze and store embryos, eggs, or sperm.

D&C (Dilation and Curettage): A procedure used to dilate the cervix, reduce the lining of the uterus and remove contents of the uterus.

Donor Insemination (DI): Artificial insemination with donor sperm.  The specimen is inserted close to the woman’s cervix.

Doxycycline:  An antibiotic that inhibits many of the microorganisms infecting the reproductive tract.

Ectopic Pregnancy: A pregnancy, which implants outside the uterine cavity usually in the fallopian tube, the ovary, or the abdominal cavity

Egg Donor: A woman who provides eggs or "ova" for another woman who has no eggs, or whose eggs are not viable. Donated eggs are fertilized and transferred to the uterus of the infertile woman.

Egg Retrieval (ER): Removal of the eggs from the ovary.

Embryo: The earliest stage of pregnancy from the point of conception to the eighth week of pregnancy.

Embryo Transfer (ET): Embryos are placed into the uterus via a catheter, usually 3-5 days after retrieval.

Endometrial Biopsy: A procedure during which a sample of the uterine lining is collected for microscopic analysis.

Endometriosis: The presence of endometrial tissue (the uterine lining) in areas outside of the uterus such as the tubes, ovaries, and peritoneal cavity. This condition often causes infertility and painful menstruation.

Endometrium: The tissue lining the uterus. This tissue responds to the cyclic production of ovarian hormones and permits implantation of the placenta during pregnancy.

Epididymis: A coiled, tubular organ attached to and lying on the testicle. Within this organ the developing sperm complete their maturation and develop their swimming capabilities. The matured sperm leave the epididymis through the vas deferens.

Estradiol Level (E2 Level): The amount of one type of estrogen in the blood.

Estrogens: A group of female hormones, produced mainly by the ovaries, responsible for the development of secondary sexual characteristics during puberty. Estrogen plays an important role in fostering changes in the endometrium during the first half of the menstrual cycle, that allows an embryo to implant.

Fallopian Tubes: Small passageways that conduct eggs from an ovary to the uterus. Fertilization occurs as an egg travels through a fallopian tube.

Fertility Specialist:  A physician specializing in the practice of fertility. The American Board of Obstetricians and Gynecologists certifies a subspecialty for OB-GYNs who receive special training in endocrinology (the study of hormones) and infertility.

Fertilization: The combining of sperm and egg. This process typically occurs inside the Fallopian tube (in vivo) but can occur in a petri dish (in vitro).

Fetus: 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.

Follicles: Fluid-filled sacs in the ovary which contain the eggs.

Follicle Stimulating Hormone (FSH): A pituitary hormone that stimulates spermatogenesis in the male and follicular development in the female.  Elevated FSH levels indicate gonadal failure in both genders.

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.

Gametes: Sex cells that contain half of a person’s genetic information. Male gametes are called sperm; female gametes are celled eggs or ova.

Gestational Carrier: A woman in whom a pregnancy resulted from fertilization with third-party sperm and oocytes. She carries the pregnancy with the intention or agreement that the offspring will be parented by one or both of the persons that produced the gametes.

Gestational Sac: A fluid-filled structure containing an embryo that develops early in pregnancy usually within the uterus.

Gonadotropins: Potent fertility drugs that provide the patient with FSH and LH, or FSH alone.

Gonadotropin Release Hormone (GnRH): A hormone that controls the synthesis and release of the pituitary hormones, follicle stimulating hormone (FSH) and luteinizing hormone (lh). GnRH is produced by the hypothalamus.

Gonadotropin Release Hormone Agonists (GnRH Agonists): Fertility drugs used to prevent the pituitary gland from releasing FSH and LH hormones. FSH and LH aid in normal ovulation, but may interfere with assisted reproductive treatments.

Gonadotropin Release Hormone Antagonists (GnRH Antagonists): Fertility drugs that like GnHR agonists, suppress ovulation. GnRH antagonists are effective at immediate preventing LH release.

Hirsutism: The overabundance of body hair found in women with excess androgens.

Hormone: A chemical substance produced by one organ in the body that regulates the activity of another organ.

Host Uterus: Also called a "gestational mother." A couple’s embryo is transferred to another woman who carries the pregnancy to term and returns the baby to the genetic parents immediately after birth.

Human Chorionic Gonadotropin (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: A combination of hormones FSH and LH, used to mature eggs in some fertility treatments.

Hypothalamus: A part of the brain, the hormonal regulation center, located adjacent to and above the pituitary gland. In both the man and the woman this tissue secretes GnRH.

Hysterosalpingography (HSG): An x-ray procedure used to determine whether the fallopian tubes are open and of normal caliber. The physician injects dye into the uterus through the cervix. The dye passes through the tubes if they are open. An HSG can also reveal information such as the configuration of the uterus, irregularities, and the presence of fibroids.

Hysteroscopy: A surgical procedure in which a telescope-like device is inserted through the cervix to view the inside of the uterus. This procedure is sometimes performed in conjunction with a laparoscopy.

Implantation (Embryo): The embedding of the embryo into tissue so it can establish contact with the mother’s blood supply for nourishment. Implantation should occur in the lining of the uterus; however, in an ectopic pregnancy it may occur elsewhere in the body.

Infertility: The inability to conceive over a period of time (typically, one year for a female who is under the age of 35 or six months for a female over the age of 35) despite intercourse without the use of contraception.

Intracytoplasmic Sperm Injection (ICSI): A laboratory procedure in which a single sperm is directly injected into a single egg.

In Vitro Fertilization (IVF): A procedure in which one or more eggs is fertilized by sperm outside the human body.

Karyotyping: A test performed to allow microscopic evaluation of blood or tissue, to analyze chromosomes for the presence of genetic defects.

Laparoscopy: Any procedure using a laparoscope, a slender tool with an attached camera that enables a physician to see the inside of the body. Infertility specialists perform laparoscopy to view a woman’s reproductive organs. Laparoscopy can be used for diagnostic purposes or to perform surgical functions such as removing damaged tissue and releasing fluids from ovarian cysts.

LH Surge: A release of large amounts of luteinizing hormone (LH) during a woman’s cycle, which normally results in the release of a mature egg from a follicle, resulting in ovulation.

Lupron: A medication that can create a pseudo-menopause. Lupron suppresses a woman’s secretion of FSH and LH. Lupron may improve the response to stimulation, as well as preventing premature ovulation, decreasing the risk of a cancelled cycle. It may also be used to treat fibroids or endometriosis.

Lupron "Down Regulation": A treatment with small amounts of Lupron that allows suppression of LH and FSH. Luteal Phase: The days of a menstrual cycle following ovulation and ending with menses, which is generally 12-14 days.

Luteinizing Hormone (LH): A hormone that causes the ovary to produce estrogen and to release a mature egg (ovulation). In the male, LH stimulates testosterone production. The anterior pituitary secretes LH.

Micromanipulation: Procedure in which an egg or an embryo is manipulated under the microscope including ICSI, Assisted Hatching, and embryo biopsy for PGD.

Microsurgical Epididymal Sperm Aspiration (MESA): A procedure in which spermatozoa are obtained from the epididymis by either aspiration or surgical excision.

Miscarriage: Loss of a clinical pregnancy prior to 20 weeks gestation.

Motility: The percentage of moving sperm in a semen sample. Normally, 50% or more sperm move rapidly.

Multiple Gestation/Pregnancy: The conception of two or more fetuses in the same woman at the same time, whether or not they result in live births.

Ovarian Failure: The failure of the ovary to respond to FSH stimulation. Diagnosed by elevated FSH in the blood.

Ovarian Hyperstimulation Syndrome (OHSS): A possible side effect of medically induced ovulation, characterized by swollen, painful ovaries and, in some cases, the accumulation of fluid in the abdomen and chest.

Ovaries: Female sex organs that release mature eggs and produce the hormones estrogen and progesterone.

Oligo-Ovulation: Irregular ovulation.

Oligospermia: A condition in which the number of sperm in a semen sample is abnormally low.

Oocyte: The egg cell produced in the ovaries. Also called the ovum or  female gamete.

Ovulation: Release of a mature egg from a follicle at the surface of the ovary.

Ovulation Induction: The use of hormones to stimulate egg development and release.

Pap Smear: A screening test to evaluate the cells of the cervix to determine whether they are normal or cancerous.

Pelvic Inflammatory Disease (PID): An infection of the pelvic organs that can cause severe illness, high fever, and extreme pain. PID may lead to tubal blockage and pelvic adhesions, which can cause infertility.

Percutaneous Epididymal Sperm Aspiration (PESA): A procedure in which sperm are removed from the epididymis, a long coiled tube above each of the testes, through a needle.

Pituitary Gland: The master gland; the gland that is stimulated by the hypothalamus and controls all hormonal functions. Located at the base of the brain just below the hypothalamus, this gland controls many major hormonal factories throughout the body including the gonads, the adrenal glands, and the thyroid gland.

Polycystic Ovarian Syndrome (PCO, PCOS): A metabolic condition in women which can cause a woman to not ovulate regularly. Though PCO can be without symptoms, some symptoms include obesity, acne, excessive hair growth, irregular menstrual periods, and infertility.

Preimplantation Genetic Diagnosis (PGD): Screening of cells from preimplantation embryos for the detection of genetic and/or chromosomal disorders before embryo transfer.

Premature Ovarian Failure (POF): The loss of ovarian function associated with high levels of gonadotropins and low levels of estrogen before age 35. The ovary may intermittently produce mature follicles.

Progesterone: The hormone produced by the corpus luteum during the second half of a woman’s cycle. It prepares the lining of the uterus to accept implantation of a fertilized egg. It is released in pulses, so the amount in the bloodstream is not constant.

Prolactin: A hormone produced by the pituitary that plays an important role in preparing the breasts, during pregnancy, for nursing. An elevation may interfere with normal ovulation.

Recipient: In an ART cycle, refers to the woman who receives an oocyte or an embryo from another woman.

Rubella Titer: A blood test that determines if the patient is immune to rubella (German measles), a viral disease that can cause severe birth defects. If a woman is not immune to rubella, she may be advised to have a rubella vaccination, wait one month before attempting pregnancy, and the retest for immunity.

Secondary Infertility: The inability to conceive or carry a pregnancy after having conceived and carried one or more pregnancies.

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. Semen provides nourishment and protection for the sperm and is a medium through which the sperm travel to the woman’s vagina. Semen may also refer to the entire ejaculate, including the sperm.

Semen Analysis (SA): A microscopic examination of freshly ejaculated semen to evaluate the number of sperm (count), the percentage of moving sperm (motility), and the size and shape of the sperm (morphology).

Sonogram (Ultrasound):  Use of high-frequency sound waves for creating an image of internal body parts. Used to detect and count follicles and to monitor pregnancy.

Sperm: Male sex cells, or gametes. Sperm, medically referred to as spermatozoa, are mobile cells that fertilize eggs. Sperm determine an embryo’s sex.

Stimulation: Administration of hormones that induce development of multiple ovarian follicles.

Superovulation: Stimulation of multiple ovulation with fertility drugs; also known as controlled ovarian hyperstimulation (COH).

Testicular Sperm Aspiration (TESA): A procedure in which spermatozoa are obtained directly from the testicle by either aspiration or surgical excision of testicular tissue.

Testicular Sperm Extraction (TESE): A sperm aspiration method in which a small section of tissue from one or both of the testicles is removed through one or more short incisions in the scrotum. Sperm are extracted from the tissue by an embryologist and used, through ICSI, to fertilize a woman’s eggs.

Testicles: The two male sexual glands contained in the scrotum, which secrete testosterone and produce sperm.

Testicular Biopsy: A small excision of testicular tissue to determine the ability of the cells to produce normal sperm.

Testosterone: The male hormone responsible for the formation of secondary sex characteristics and for supporting the sex drive. Testosterone is also necessary to create sperm.

Thyroid Gland: The gland in the front of the neck that produces thyroid hormones to regulate the body’s metabolism.

Urethra: The tube through which urine passes from the bladder and the outside of the body. This tube also carries semen, in the male, from the area of the prostate to the outside.

Uterus: The muscular structure that nurtures and protects a growing fetus. The uterus, often referred to as the womb, is connected to the vagina by the cervix.

Vagina: The canal leading from the cervix to the outside of the woman’s body; the birth passage.

Vaginal Ultrasound: Imaging technique used to view the uterus, ovaries, fetus, and other soft tissues by projecting sound waves through a probe inserted into the vagina..

Varicocele: A collection of varicose veins in the scrotum which may be associated with poor sperm quality.

Vitrification: A type of cryopreservation, which involves rapid cooling that helps to prevent formation of ice crystals that can damage to the cell. May be used to freeze embryos and oocytes.

Zygote: A fertilized egg or embryo in the early stages of development.