Pregnancy Length: Why 40 Weeks, Not 9 Months?

Pregnancy typically lasts for about 40 weeks, or approximately 280 days, from the first day of your last period to the date of birth. However, it's important to note that the actual length of pregnancy can vary from woman to woman. Some women may give birth sooner or later than 40 weeks.

The reason why pregnancy is measured in weeks rather than months is because it is more precise. If you divide the average length of pregnancy by the number of weeks, you get an average week of 7 days. This allows healthcare professionals to track the progression of pregnancy more accurately.