Using both the date of your last period and the length of your regular cycle, or exact date of conception, our pregnancy due date calculator will quickly work out your estimated due date, tailoring it accordingly for longer, shorter, and average cycle lengths. To calculate your due date, your doctor will take the first day of your last menstrual period (LMP), and add 280 days (the equivalent of 40 weeks).
![weeks according to due date weeks according to due date](https://i.redd.it/jbsd4g7hsq151.jpg)
On average, human pregnancies last 266 days (from conception) or roughly 40 weeks (38 weeks from. If dating by ultrasonography performed between 14 0/7 weeks and 15 6/7 weeks of gestation (inclusive) varies from LMP dating by more than 7 days, or if ultrasonography dating between 16 0/7 weeks and 21 6/7 weeks of gestation varies by more than 10 days, the EDD should be changed to correspond with the ultrasonography dating Table 1.Between 22. Babies rarely keep to an exact timetable, so your full-term pregnancy can be anywhere from 37 and 42 weeks. i.e (Due Date LMP + 280 days) LMP - First day of last menstrual period. There are several ways to determine when your baby will be due. This is an estimated date of when your baby is due. LMP Method: Using LMP method, you can calculate the due date by adding 40 weeks to first day of your last menstrual period. Luckily, our pregnancy due date calculator can help. Due date is the estimated date of delivery calculated by two methods, using last menstrual period and other one is using conception date.
![weeks according to due date weeks according to due date](https://i.ytimg.com/vi/Y7KyluuW3-0/maxresdefault.jpg)
Unless you can pinpoint exactly what point of your ovulation cycle you were in at the time of fertilization, it’s difficult to know how far along you are and what date you’ll meet your baby. If you happen to know the day you conceived, you can count 38 weeks from that day to find your due date. That means that simply estimating nine months from the day you take a pregnancy test isn’t going to calculate your due date, and, even so, factoring in a few weeks here and there for ovulation won’t either. Many won’t be aware of their pregnancy until their first missed period, and by that time they could be up to five weeks in. However, the time of conception is often not known exactly.
![weeks according to due date weeks according to due date](https://blog.pregistry.com/wp-content/uploads/2018/04/due-date-c-new-11.png)
Most expectant mothers don’t realize that both menstrual and ovulation periods count as the first two weeks of pregnancy. Your baby will be born around the 38th and 40th week after conception. While it’s true that most pregnancies last 40 weeks, there are other factors at play which will determine your pregnancy due date.