Pregnancy in weeks, months, and trimesters - BabyCenter
https://www.babycenter.com/pregnancy/your-body/pregnancy-in-weeks-months-and-trimesters_10326878
WebHow many weeks are in a trimester? Each trimester is 13 or 14 weeks long. The first trimester lasts until you're 13 weeks pregnant, the second trimester spans week 14 to week 27, and the third trimester starts the day you turn 28 weeks pregnant and lasts until week 40 (or until you deliver your baby). How many trimesters are in a pregnancy?
DA: 1 PA: 94 MOZ Rank: 24