Pregnancy

Learn how researchers use biobanks, such as the Improved Pregnancy Outcomes by Early Detection study, or IMPROvED to improve maternal and newborn outcomesSee all videos for this article

pregnancy, process and series of changes that take place in a woman’s organs and tissues as a result of a developing fetus. The entire process from fertilization to birth takes an average of 266–270 days, or about nine months. (For pregnancies other than those in humans, see gestation.)