30 weeks pregnant
Doctors count pregnancy from the first day of the last period. This page shows what week 30 looks like in dates and lets you work out your own due date.
How it works
The due date is 280 days after the first day of your last period. Weeks of pregnancy are the days since that first day divided by 7. Here 30 weeks times 7 is 210 days.
Worked example
Take a last period that began on 7 June. Add 280 days to get a due date of 14 March. Add 210 days to reach 3 January, the start of week 30. 210 divided by 7 is 30. That leaves 70 days to go. Dates in this example use a year with 365 days.
Common questions
Which trimester is week 30?
Third trimester. The first trimester covers weeks 1 to 13, the second covers weeks 14 to 27 and the third runs from week 28 to the birth. Week 30 is week 3 of the third trimester.
Why do weeks start from the last period and not conception?
Most people know the date of their last period but not the day of conception. Counting from the last period gives everyone the same starting point. A pregnancy is about two weeks longer on paper than from conception. Counted from conception, this would be week 28, which is 196 days.
How accurate is a due date?
Only a small share of babies arrive on the due date. Most arrive within a couple of weeks either side. Treat the date as the middle of a window. Here the due date is 14 March, and 70 days remain from week 30.
What if my cycle is not 28 days?
The 280 day rule assumes ovulation near day 14. If your cycle is much longer or shorter, your doctor may adjust the due date, often with an ultrasound. With a 35-day cycle some clinicians add 7 days, which would move 14 March to 21 March.
Does a leap year change the due date?
It can. A year with an extra day in February moves dates after that day by one. The calculator above uses the real calendar for your dates. If the span from 7 June includes a 29 February, 14 March reads one day earlier, as 13 March.