Supporting you, Campaigning for all
• Campaigning for better births for all
• Protecting human rights in childbirth
• Independent information about pregnancy and birth
• Raising awareness of research

For a better birth

Latest Content

Journal

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Pregnancy and hearing: Did you know…

AIMS Journal, 2024, Vol 36, No 4 Did you know that one in three pregnant women develop tinnitus compared with one in ten who are not pregnant? Tinnitus is the sensation o…

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Editorial: Hello and welcome. How a…

AIMS Journal, 2024, Vol 36, No 4 By Alex Smith Welcome to the December 2024 edition of the AIMS journal. The theme for this quarter considers the experience of care for d…

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Welcome to the Deaf Community – a l…

AIMS Journal, 2024, Vol 36, No 4 By a hearing mother of a deaf baby Sat in the hospital ward, I snapped a cute picture on my phone of my tiny little newborn wearing a hea…

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Events

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UK Perinatal virtual conference

Ten years of MBRRACE-UK reporting: looking back, looking ahead MBRRACE-UK perinatal confidential enquiry into the care of migrant women with language difficulties Nationa…

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AIMS Workshop: Focus on Resolution

Join us for the an interactive online AIMS workshop "Focus on Resolution" with Dr Rebecca Moore . Tickets available here https://www.tickettailor.com/events/aims/1285321…

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AIMS Workshop: Focusing on Rights i…

Join us for another in our new series of interactive online AIMS workshops, " Focusing on Rights in Pregnancy and Birth ". Tickets available here https://www.tickettailor…

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Latest Campaigns

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AIMS Letter to Wes Streeting

AIMS has written to Wes Streeting MP, welcoming him to the role of Secretary of State for Health and Social Care. We acknowledge his awareness that maternity services are…

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Involving Service User Voices in Ma…

This is an edited version of an invited talk given by Jo Dagustun, AIMS Campaigns Team, to the International Labour and Birth Research Conference UK, 24 - 26 April 2023.…

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Birth Trauma Inquiry Open Letter in…

We write this letter in response to the recently published APPG Report on Birth Trauma which can be found here The report was extremely moving and we honour the brave con…

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Pregnancy Calculator i

When's your due date?

What does your "due date" mean? How long is a normal pregnancy? How might being given a due date affect you and your baby? Enter the first day of your last period to discover when you're most likely to give birth.... and to find out more about due dates, induction and "post date" babies.
You are weeks pregnant.
Date of the first day of your last period
Adjusted cycle length

Date of the first day of your last period

The date of your last period allows an estimation of when you ovulated and conceived your baby.

A surprising number of women will have a bleed after they are pregnant, and although seeking advice from a doctor or midwife is recommended, usually this bleeding is not a problem.

Adjusted cycle length

Your menstrual cycle is counted from the first day of one period to the first day of the next. The average menstrual cycle is 28 days long, but many women will have longer or shorter cycles than this.

Ovulation usually takes place about 14 days before the next period. This means in a short cycle ovulation will be less than 14 days after your last period and with a long cycle more than 14 days after your last period. Giving the length of the cycle allows this to be taken into account in calculating your due date.

Many women have irregular cycles which make using the last day of their period less reliable for estimating due date.