g lossary of m edi C al t erms
Advanced maternal age (ama): Traditionally deﬁned as when a woman is older
than thirty- ﬁve at the time of delivery. In women older than thirty- ﬁve
there are increased ge netic risks in pregnancy, due to the aging pro cess
of the human egg and resultant chromosomal abnormalities. Fertility rates
decline and miscarriage rates increase with ama.
Assisted reproduction: Also known as assisted conception, a number of advanced
medical techniques to aid fertilization, thereby achieving pregnancy in
couples with infertility (see below). In vitro fertilization (see below) is the best-
known of the assisted reproduction techniques.
Assisted reproductive technology (art): All fertility treatments in which both eggs
and sperm are handled. In general, art procedures involve surgically remov-
ing eggs from a woman’s ovaries, combining them with sperm in the labora-
tory, and returning them to the woman’s body or donating them to another
woman. In vitro fertilization (see below) is the best- known art.
Azoospermia: See male infertility, below.
Blastocyst transfer: A recent advance in infertility treatment, which involves
growing human embryos in the laboratory to a later “blastocyst” stage before
transferring them into the uterus following a cycle of in vitro fertilization (see
below). With a blastocyst transfer, fewer embryos are transferred, but preg-
nancy rates are just as high. The technique thus virtually eliminates the risk
of a high-order multiple pregnancy (see below).
Blighted ovum: Also known as an anembryonic pregnancy, this occurs when a
fertilized egg is implanted in the uterus but does not develop into an embryo.
The condition causes nearly half of all miscarriages in the ﬁrst trimester of
pregnancy and thus is a leading cause of early miscarriage.
Choco late cyst: Also called an endometrioma or an endometrial cyst, an ovarian
cyst that contains fluid and sometimes semisolid material, including old,
dark blood that grossly resembles choco late. These cysts are related to severe
endometriosis (see below).