Pregnancy Week to Week

Pregnancy Week by Week Information

Calculating Due Date

In order to calculate your pregnancy due date, of EDD, just count from the first day of your last period. Then subtract 3 months and add 7 days to this date. Known as Naegeleís Rule, this method is based on the thought that a woman ovulates on day 14 of her cycle. Ovulation causes the body to increase slightly in temperature. For women who ovulate after day 14 of their cycle, a method which calculates using the first day of an overall thermal shift, subtracting 7 days and adding 9 months works better. This method is known as Premís Rule. An average pregnancy lasts about 280 days or 40 weeks. To help with the process, there are numerous online due date calculators which merely ask for the date of your last period and do all the calculations for you. However accurate you may believe the due date to be, a large portion of babies are not born on their estimated dates. In fact, about 8-% are born within 10 days after the calculated date. This is known as a full term pregnancy which can extend to about 42 weeks. About 8-10% of babies are born before their estimated due dates. Premature babies also fall into this category, although depending on just how premature or early, the baby has varying survival potentials. Knowing the pregnancy due date is important for determining if the pregnancy is progressing smoothly and if the baby is developing correctly for each developmental stage.

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