Calculating your due date is easy, it takes 9 months to have a baby, everybody knows that well that is not quite right. Pregnancy is based on a 40-week (280-day) calendar. To calculate your estimated date of delivery, add seven days to the first day of your last normal period, then add nine months. If you know the date of conception work from that but most of us can’t be that sure so its best to use that method. Your baby is considered full term if they arrive anywhere from three weeks before to two weeks after this date (more than 90 percent of babies do). The most accurate way to date a pregnancy is via ultrasound measurement of the foetus’s crown to bottom length this is usually carried out between eight and 12 weeks. The sex of your child is determined by your partner’s sperm. The egg and sperm each contribute one chromosome, the egg always carries an X; the sperm, either an X or a Y. If the fertilizing sperm contains an X chromosome, you will have a girl. If it contains a Y, you’re having a boy. If you choose to know the sex of the baby the ultrasound can often reveal this, however it is more accurate later in your pregnancy.
