Amniocentesis
A procedure in which a small amount of amniotic fluid is removed through a needle from the fetal sac at about 16 weeks into a pregnancy. The fluid is studied for chromosomal or other abnormalities which may affect fetal development.
Antimüllerian hormone (AMH)
A hormone which is often measured in a woman to help determine her egg supply, or “ovarian reserve.” It is secreted by small, growing follicles.
Antral follicle count
The number of follicles noted by ultrasound at the beginning of the menstrual cycle, usually day 2 or 3.
ASRM
American Society for Reproductive Medicine.
Assisted hatching (AH)
A procedure in which the zona pellucida (outer covering) of the embryo is partially opened, usually by application of an acid or laser, to facilitate embryo implantation and pregnancy.
Assisted reproductive technology (ART)
All treatments which include the handling of eggs and/or embryos. Some examples of ART are in vitro fertilization (IVF), gamete intrafallopian transfer (GIFT), pronuclear stage tubal transfer (PROST), tubal embryo transfer (TET), and zygote intrafallopian transfer (ZIFT).