Length of Pregnancy

The average pregnancy lasts approximately 40 weeks, or 10 lunar months (a lunar month is a complete cycle of the moon every 28 days.) Anywhere from 38 to 42 weeks is considered normal, which is 2 weeks before to 2 weeks after your actual due date. Keep in mind that only 5% of women actually deliver on their due date.  Your due date is generally referred to as an approximate time frame rather than as a definite ending point for your pregnancy. Unsure of what your estimated due date is?   Go to calculate your due date to find out!

Pregnancy is divided up into 3 trimesters, each trimester lasting about 13 weeks.  the beginning of your pregnancy starts with your last menstral period,  not the day you conceive.  By the time you conceive you are already considered to be 2 weeks pregnant. Some doctors and references clarify this by referring to the "age of fetus". A woman who is 14 weeks pregnant has a 12 week old fetus.  In common terms though, you are still referred to and considered to be 14 weeks pregnant.  Think of it as a two week bonus on the path of pregnancy!