How Do I Calculate the Tentative Date for the Birth of My Child?

Did you know that the longest recorded human pregnancy was of 345 days? A woman aged 25 gave birth to a healthy baby in 1945, after a pregnancy lasting a little over a year, according to an article published in New Health Guide. Normal human gestational period is 280 days or a little over 9 months. However, the gestation period may vary from one woman to another. It can both be less or more than 38 weeks.

How is the Due Date Calculated?

The pregnancy due date calculator uses the date of conception as reference for the calculation of the delivery date. However, most women do not know the exact date when they conceived. In such a case, your doctor calculates the EDD (estimated date of delivery) with reference to the first day of your last period. For women who have a normal cycle (28 days) on an average, ovulation takes place on the 14^th day, which is then followed by fertilisation, in case of pregnancy. Therefore, your doctor estimates the EDD to be 40 weeks from the first day of your last period. For women who have been tracking their ovulation, it is 38 weeks from the day of ovulation.

Another method is to deduct 3 months from the first day of your last period and then add seven days and that date is your EDD. Here is how. Let’s take an example where your last period was on June 5, then the pregnancy due date calculator will deduct 3 months, which would be March 5. Then 7 days would be added, therefore, your EDD would be March 12 of the following year.

Is the EDD Always Accurate?

The due date can be changed if your doctor estimates so. This may happen if the results of the internal examination are not in accordance with the EDD. Some of the things that are taken into account are the size of uterus and the size of the baby (which may be small or big in accordance with the term of the pregnancy so far). The EDD is also confirmed by the measurement of the fundus of the uterus as well as important milestones, such as first foetal heart beat or first foetal movement. The fundus of the uterus is known to reach the naval around 20 weeks.

Interestingly, only one in 20 women deliver on the due date calculated by pregnancy due date calculator. The baby is delivered when it is physically ready to grow outside the womb. Be sure to talk to your doctor about your EDD.