how many weeks for a pregnancy
Pregnancy usually lasts about 40 weeks (280 days) from the first day of your last menstrual period (also called LMP) to your due date. Your due date is the date that your provider thinks you will have your baby. ACOG and SMFM now define a full-term pregnancy as a pregnancy that lasts between 39 weeks, 0 days and 40 weeks 6 days. Babies born full term have the best chance of being healthy, compared with babies born earlier or later.