Amniocentesis: A before-birth diagnostic procedure during which a long needle is used to obtain amniotic fluid from within the uterus. This fluid can be used for genetic and other diagnostic tests. Informally known as amnio.
Quick GuideLice & Nits: How to Get Rid of Head Lice
Subscribe to MedicineNet's Children's Health & Parenting Newsletter
Last Editorial Review: 6/9/2016