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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Issues of trust led to me becoming…

AIMS Journal, 2024, Vol 36, No 3 By Ryan Jones This is a journal article about trust, and it’s also a journal article about my journey to becoming a volunteer at AIMS. I…

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I trust we can change

AIMS Journal, 2024, Vol 36, No 3 By Claire Dunn I found myself sitting in the waiting room of a prestigious hospital in West London pondering what lay ahead, for I was on…

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Editorial - Trust and responsibilit…

AIMS Journal, 2024, Vol 36, No 3 By Alex Smith Welcome to the September 2024 issue of the AIMS journal. The theme for this quarter explores different aspects of trust enc…

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Events

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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 are available here https://www.ticketta…

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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 are available here https://www.tickettailor.com/events/aims/12…

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AIMS Workshop: Focusing on Inductio…

Join us for an interactive online AIMS workshop, " Focusing on Induction of Labour ". Tickets are available here https://www.tickettailor.com/events/aims/1322209 Nadia Hi…

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Latest Campaigns

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NICE Maternal and Child Nutrition S…

AIMS submitted comments on the draft NICE Guideline on Maternal and child nutrition in September 2024. You can read our comments here . The NICE documents can be found he…

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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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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.