To find your due date, enter the date of the first day of your last period, and select show your due date. Pregnancy normally lasts from 37 weeks to 42 weeks from the first day of your last period. You need to know the first day of your last period to use this calculator.

How is due date calculated UK?

In the UK, where Chaney and Marshall live, a womans estimated date of delivery is first calculated by using the date of her last period and adding 280 days, or 40 weeks. That is followed by an ultrasound scan where another estimate is made, based on the size of the foetus.

When do most first time mums give birth?

The researchers found that 50% of all women giving birth for the first time gave birth by 40 weeks and 5 days, while 75% gave birth by 41 weeks and 2 days. Meanwhile, 50% of all women who had given birth at least once before gave birth by 40 weeks and 3 days, while 75% gave birth by 41 weeks.

When do most first time mums give birth UK?

Most babies arrive between 37 weeks and 41 weeks of pregnancy, usually within a week either side of their due date. Twins and particularly triplets are more likely to be born premature. The due date you are given at your dating scan will be more accurate than using your last period to calculate it.

How many days over do first time mums go?

First time moms, if left alone to go into labor naturally tend to be pregnant for about 41 weeks and 1 day. Women whove had babies before tend to deliver around 40 weeks and 3 days. Only about 10% of women go longer than 42 weeks. Thats average.