how many weeks in a trimester pregnancy
A normal, full-term pregnancy can range from 37-42 weeks and is divided into three trimesters. Each trimester lasts between 12 and 14 weeks. The first trimester lasts from the first through the 13th week of pregnancy. Although you may not look pregnant during the first trimester, your body is going through enormous changes as it accommodates a growing fetus. In the first few weeks following conception, your hormone levels change significantly.