Definition of In vitro fertilization

In vitro fertilization: IVF, a laboratory procedure in which sperm are placed with an unfertilized egg in a Petri dish to achieve fertilization. The embryo is then transferred into the uterus to begin a pregnancy or cryopreserved (frozen) for future use. IVF was originally devised to permit women with damaged or absent Fallopian tubes to have a baby. Normally a mature egg is released from the ovary (ovulated), then enters the Fallopian tube, and waits in the neck of the tube for a sperm to fertilize it. With defective Fallopian tubes, this is not possible. The first IVF baby, Louise Joy Brown, was born in England in 1978.

In vitro fertilization literally means "fertilization in glass." A child born by in vitro fertilization is inaccurately known a "test tube baby."