IVF Glossary

pituitary gland

a small gland in the brain just beneath the hypothalamus that produces and secretes FSH, LH, and hCG.

polycystic ovary syndrome (PCOS)

a common endocrine disorder in women of reproductive age in which the body's sex hormones are not balanced, which may impair fertility.Characterized by enlarged ovaries with many antral follicles.

preimplantation genetic diagnosis (PGD)

a screening test used to determine if specific genetic or chromosomal disorders are present in embryos.

preimplantation genetic screening (PGS)

a test used to screen embryos for chromosome abnormalities.


a hormone that, in women, is secreted during the second half of the menstrual cycle and prepares the lining of the uterus for implantation of a fertilized egg.

Adapted from Assisted Reproductive Technology: A Guide for Patients. American Society for Reproductive Medicine, 2011.