U. S. Sen. Hillary Rodham Clinton, D-NY, and, former President Bill Clinton, blow out the candles on a cake at Hillary Rodham Clinton's 59th birthday party at Tavern on the Green in New York, Thursday, Oct. 26, 2006.
The unborn baby spends around 38 weeks in the uterus, but the average length of pregnancy, or gestation, is counted at 40 weeks. Pregnancy is counted from the first day of the womanâs last period, not the date of conception which generally occurs two weeks later.
The delivery of a full-term newborn refers to delivery at a gestational age of 37-42 weeks, as determined by the last menstrual period or via ultrasonographic dating and evaluation. The Naegel rule is a commonly used formula to predict the due date based on the date of the last menstrual period.