Third, the gravitational effect of the moon is just as potent during new moonsâwhen the moon is invisible to usâas it is during full moons. There is a more serious problem for fervent believers in the lunar lunacy effect: no evidence that it exists.
Answer: Each pregnancy is divided into three trimesters. Each trimester is roughly a third of your pregnancy. These three trimesters have different emotional and physical happenings that make them unique. Here is a guided tour through each trimester:
A normal pregnancy lasts for 40 weeks. A perfect normal full term pregnancy is 40 weeks. However, it is normal to go into labor at 37-38 weeks. How Many Weeks Is Pregnancy. 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.