how many weeks gestation is full term
A perfect normal full term pregnancy is 40 weeks. However, it is normal to go into labor at 37-38 weeks. A full term pregnancy is 40 weeks, but it is safe to delivery a baby between 38-42 without it having any health issue. 40. 40 weeks from the first day of your last period.  as said by brain child is correct. that is how the due date is calculated.