Androgen:  a testosterone-like hormone that stimulates the male sex drive and can contribute to female infertility.

Antibodies: proteins that are found in blood and are used by the immune system to identify and neutralize foreign objects, such as bacteria and viruses.

Alternative/Artificial Insemination (AI):  procedures involving inserting sperm into a woman’s vagina, cervix, uterus or fallopian tubes.

Assisted Reproductive Technologies (ART):  any fertility procedure in which both eggs and sperm are manipulated outside the body in a laboratory.

Basal Body Temperature (BBT):  the body temperature at rest. A slight rise in the BBT indicates that ovulation has occurred.

Blastocyst:  a thin-walled hollow structure in early embryonic development that contains a cluster of cells. It is preceded by a zygote, the fertilized egg cell, and succeeded by an embryo.

Chromosome:  microscopic units on a gene that carry the genetic information that is passed on to offspring.  

Clomiphene citrate (Clomid or Serophene): a fertility enhancing drug which stimulates ovulation through the release of gonadotropins from the pituitary gland.

Corpus luteum:  the fluid filled sac post ovulation in which the egg matures (the follicle) that continues to produce hormones that prepare the uterine lining to accept and nurture the fertilized egg.

Cryopreservation of Gametes:  the process of freezing sperm and eggs for later use.

Cytoplasm: the part of the interior of a cell outside the nucleus.

Egg or oocyte donor:  a woman who allows her eggs to be used to create a child whom she does not intend to parent (or to be used in scientific research), whether or not in exchange for compensation.

Egg Retrieval:  the process of using hormonal drugs to hyperstimulate a woman’s ovaries to produce multiple eggs per menstrual cycle, retrieving those eggs from the woman’s body and using them for her own reproduction or donating them for reproduction or science.

Embryo: a multi-celled fertilized egg, up to 8 weeks of development.

Endocrine disruptor:  hormone-like pollutants that either mimic or block normal hormone functioning in the body.

Endometriosis:  a disease in which tissue from the uterine lining grows outside of the uterus.

Fecundability:  the monthly probability of conceiving.

Female factor infertility: infertility that can be attributed to a reproductive problem in the female partner.

Fetus:  a prenatal developing human from the 8th week of gestation until birth.

Follicle: a structure in the ovary in which an unfertilized oocyte matures and is surrounded by one or more layers of cells; also used to refer to the actual  oocyte itself surrounded by follicular cells.

Follicle-Stimulating Hormone (FSH):  a hormone, secreted by the anterior pituitary gland, which promotes the development of ova in the female and testicular function in the male.

Gamete: human reproductive cells; ova in women and sperm in men.

Gamete Donation:  the donation of one’s sperm and eggs to aide a woman and/or couple achieve pregnancy.

Gamete Intrafallopian Tube Transfer (GIFT):  similar to IVF and ZIFT, except both eggs and sperm are transferred to the woman’s fallopian tube so fertilization can occur within the woman’s body.

Genetic or Traditional Surrogate:  a woman who uses her own eggs and undergoes artificial insemination to create a pregnancy and give birth to a child who will be raised by others, whether or not in exchange for compensation.

Gestational Mother:  a woman who carries and gives birth to a child to whom she is not genetically related but whom she intends to parent.

Gestational Surrogate:  a woman who agrees to be impregnated with another woman’s fertilized egg and give birth to a child who will be raised by others, whether or not in exchange for compensation.

Gonadotropins: protein hormones, follicle stimulating hormone (FSH) and luteinizing hormone (LH), secreted by the pituitary gland and used in fertility enhancing drugs to directly stimulate the ovary to produce more follicles and release more mature ova.

Gonadotropin-Releasing Hormone (GnRH): hormone secreted by the hypothalamus that prompts the pituitary gland to release follicle-stimulating hormone (FSH) and luteinizing hormone (LH) into the bloodstream.

Infertility:  the inability to conceive naturally after one year of frequent unprotected sexual intercourse.

Intracytoplasmic Sperm Injection (ICSI):  a specialized form of the IVF procedure during which one single sperm is manually injected into the cytoplasm of an egg.

Intrauterine Insemination (IUI):  a form of artificial insemination during which the sperm is placed directly into a woman’s uterus.

In Vitro Fertilization (IVF):  the creation of an embryo by combining sperm and egg in a laboratory dish.

Lutenizing hormone (LH):  a hormone secreted by the pituitary gland that stimulates ovulation in females and the secretion of testosterone in males.

LH Surge:  the spiking release of luteinizing hormone (LH) that causes release of a mature egg from its follicle.

Male Factor Infertility:  infertility that can be attributed to a reproductive problem in the male partner.

Oocyte: an unfertilized egg undergoing maturation in the follicular stage.

Ooplasm:  the cytoplasm of an ovum.

Ooplasmic Transfer:  the transfer of the ooplasm of one woman’s eggs into the eggs of another woman undergoing IVF; the resulting embryo has genetic material from three parents, which has raised concern among the FDA.  The procedure was deemed too experimental and it was determined that more preclinical trials were needed before the FDA would allow procedures to continue in clinics.

Ovum/Ova (pl.): an unfertilized, but mature human egg released during ovulation.

Polycystic Ovarian Syndrome (PCOS):  a genetically-linked hormonal imbalance that prevents ovulation. PCOS may also cause overproduction of estrogen, abnormal thickening of the uterine lining, very heavy and/or irregular periods, as well as acne and facial hair. The latter are caused by an overproduction of male hormones, including testosterone.

Preimplantation genetic diagnosis (PGD):  the process of testing an embryo for genetic characteristics before or to exclude transfer of the embryo into the woman’s body during IVF procedures.

Premature Ovarian Failure:  also called early menopause, this can result from exposure to certain chemicals, chemotherapy and radiation for cancer treatment. Other causes are certain genetic disorders and certain immunological abnormalities.

Prolactin:  a female hormone, produced by the pituitary gland, that controls lactation (breast milk production). Elevated prolactin levels may interfere with ovulation.

Salpingitis:  infection, inflammation and scarring of the fallopian tubes.

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

Stem Cell: cells with the potential to develop into many different cell types in the body.

Surrogacy: See “Gestational Surrogate” or “Genetic/Traditional Surrogate.” 

Zygote: a one-celled fertilized egg.

Zygote Intrafallopian Transfer (ZIFT):  similar to IVF, except the zygote is placed directly into the woman’s fallopian tube through invasive surgery.