Gestation Calculator

This calculator has been designed to give you an idea of the treatment options available to you*. If you decide to have an abortion with Marie Stopes UK, one of our nurses will give a more approximate gestation date during your appointment by way of a scan.
*Please note that this online calculator will only give you an estimated gestation based on the details you have provided.

Please select the first day of your last menstrual period.



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Call us now on 0345 300 8090 or email services@mariestopes.org.uk

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How many weeks pregnant am I?

If you've had a positive pregnancy test, there's a simple way to find out how many weeks pregnant you may be. Just use the gestation calculator below and it will automatically work it out for you.

All you need to do is enter the first day of your last period.

If you've had a positive pregnancy test or are thinking about having an abortion, it's important to know how many weeks pregnant you are as this will affect your options. Medical abortion (the abortion pill(s)), for example, is only recommended for women up to 9 weeks and 4 days at Marie Stopes UK.

Find out more about all of your options

Unprotected sex

You may be pregnant if you've had unprotected sex. If you've had unprotected sex within the last 5 days and don't want to be pregnant, you can use emergency contraception such as the emergency contraceptive pill or IUD to ensure any pregnancy doesn't continue. If you've had unprotected sex more than 5 days ago and are unsure whether you're pregnant, you will need to do a pregnancy test after about 3 weeks, if your period is late, or if you have any abnormal vaginal bleeding.

Need to talk about your options?

Our specialist staff are on hand 24/7 to offer expert advice and support – from your initial consultation to treatment aftercare.

Call us now on 0345 300 8090 or email services@mariestopes.org.uk