Definition:
The term for the baby during pregnancy until 10 weeks after the last menstrual period (8 weeks after fertilization). After 10 weeks' gestation, the baby is called a fetus.
From Krissi Danielsson, former About.com Guide
Updated May 31, 2008
About.com Health's Disease and Condition content is reviewed by the Medical Review Board
The term for the baby during pregnancy until 10 weeks after the last menstrual period (8 weeks after fertilization). After 10 weeks' gestation, the baby is called a fetus.