The Three Stages of Pregnancy (1st, 2nd, and 3rd Trimester)

Pregnancy is measured in trimesters from the first day of your last menstrual period (LMP) and normally lasts about 40 weeks from conception to the birth of a baby. This time is roughly divided into 3 periods: the first trimester, second trimester and third trimester.
The first trimester is measured from conception to about the 12th week of pregnancy; the second trimester, from about 13 to 27 weeks of pregnancy; and the third trimester, from about 28 weeks of pregnancy until birth. Let's see what happens with you and your baby during each of the three stages.