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Ultimate Due Day Calculator

Pregnancy Due Date Calculator

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Pregnancy: due date

Knowing the due date of your unborn baby is an integral part of pregnancy and preparing for the arrival of the baby. From things like preparing the nursery to getting ready for labor and giving birth, its important that you know the most accurate estimation of your due date. The key to this lies on knowing the exact date of your last period, with that information you can estimate with close accuracy the expected date of your delivery.


Information needed for an accurate estimate

For an accurate estimation on the due date of your unborn baby you need to have or know the following information:

  • Date of your last period
  • Accurate information on the duration of your menstrual cycle
  • Any information concerning menstruation irregularities especially during the months surrounding your conceiving
  • Personal history or family history of premature births and or late births
  • Documented prenatal visits


How long does a normal pregnancy last?

The normal length of a pregnant woman is 40 plus or minus two weeks. Meaning it can last anywhere between 38 to 42 weeks. Anything below 38 is considered premature birth and after 42 weeks it is considered a late birth.


How is pregnancy calculated?

State of pregnancy is calculated from the first day of your last period. Meaning is you want to know how far along you are with your pregnancy, you go to the last day of your last period and start counting from the day that follows. If you want to estimate your due date you count 40 weeks from the start of your last period. This is the same way your doctor will estimate your due date before verifying and confirming with an ultrasound. Just remember the baby can come two weeks earlier or two weeks later, its normal.


When is your due date?

The simplest way of calculating your due date is by subtracting 3 months from the date of your last menstrual period, then add 7 days to that result. The date you get is your due date on the following calendar year. For example, say your last period began on June 21 2016. Substrate, 3 months from June going backwards, which gets you to March, and then add 7 days. Your pregnancy due date would be March 28 plus or minus two weeks of course. Remember this is only just an estimate so do not panic when the baby comes earlier or later.


Confirming your due date

The only way to be accurate with your due date is to go for your prenatal visits, using an ultrasound machine your doctor will have a much better estimate of your delivery date. The ultrasound allow the doctor to make a much more accurate estimation of the age of your unborn baby using certain medical variations like size and organ development.


Due date estimates can be off

Due date estimating works for women with regular cycles and accurate information on their menstrual cycle. Women with irregular cycles bring challenges to calculating the estimated due date. For example, a woman who typically gets her period every seven to eight weeks and has not had her period in about 3 months. When she tests, she finds out she is pregnant, It will be difficult to find out when she conceived. That is why the estimated due date can be a bit off in some women, only going for the prenatal visits can help is adding more accuracy to the estimated date.


Other ways of confirming the estimated due date

There are other useful ways that can be used to confirm the estimated due date. These include:

  • An early ultrasound.
  • Pregnancy milestone e.g. the first time an unborn baby’s heartbeat is heard is somewhere around weeks 8 to 12 of pregnancy or the first fetal movement at around 16 to 22 weeks.
  • Fundal height measured by your doctor, it should reach the naval at around week 20.


Always remember, the EDD is only an estimate as such you should be prepared to deliver your baby a month before the due date.