Women Supporting Women
• 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


« »

An Interview with Lorna Tinsley

AIMS Journal, 2020, Vol 32, No 4 Lorna Tinsley Interview by Rachel Boldero AIMS believes that an effective Nursing and Midwifery Council (NMC) is crucial for a well-funct…

Read more

My experiences of supporting breast…

AIMS Journal, 2020, Vol 32, No 4 By Wendy Jones PhD MRPharmS MBE ‘ Scientific, evidence-led information which is very up to date and relevant, and … better informed than…

Read more

Oxfordshire Breastfeeding Support &…

AIMS Journal, 2020, Vol 32, No 4 The OBS facilitators: Charlotte Gilman, Julie Gallegos, Lisa Mansour and Jayne Joyce (left to right) By Jayne Joyce IBCLC Project Lead Ox…

Read more


« »

AIMS 60th Anniversary Event - Confe…

POSTPONED FROM JUNE 2020 Making a difference past and future The purpose of the day is to celebrate what Birth Activists in general and AIMS in particular have achieved,…

Read more

AIMS Annual General Meeting 2020

This year’s AGM will be an online meeting, so we plan to keep it to two hours. However, there will be the opportunity to stay, chat and socialise with friends and colleag…

Read more

Latest Campaigns

« »

AIMS letter to Jeremy Hunt followin…

AIMS has written this week to Jeremy Hunt MP, in his role as chair of the Health and Social Care Select Committee, as a response to the current discussion regarding a so-…

Read more

NICE Shared Decision Making Guideli…

AIMS has submitted comments on the draft NICE Shared decision making Guideline. You can read our comments here The details of the consultation on the draft guidelines can…

Read more

NICE Neonatal Infection Guideline -…

AIMS has submitted comments on the draft update of the NICE Neonatal Infection Guideline. You can read our comments here . The details of the draft guidelines can be foun…

Read more

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.