Pregnancy Calculator – Try BellyBelly’s Pregnancy Calculator



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Pregnancy Calculator – Try BellyBelly’s Pregnancy Calculator

Pregnancy Calculator

Pregnant and wondering when your baby might be due? Only around 3-5% of babies are born on their estimated due date estimated due date, with full term pregnancy classed between 38-42 weeks of pregnancy.

Dates based on your last menstrual period are most accurate, because ultrasound has a margin of error even at early stages, and is based on mathematical averages. Your body offers a more reliable estimate. That said, you can try our pregnancy calculator to get an approximate idea on when your baby will arrive.

If you are given two due dates, it’s a great idea to take the one which is furthest away, because you’ll have less pressure for an induction and your baby can be born when he/she is ready, rather than anyone else. You’ll notice by making slight adjustments to your cycle length and luteal phase in the calculator below, it can effect the due date by days – because most of our bodies don’t run to the averages which standard pregnancy calculators or charts use, as well as your doctor’s. Given that many women don’t know their cycle length and luteal phase, you can begin to see why it’s called an ‘estimated’ due date!

Trust Your Baby… He Knows His Due Date, Not Anyone Else!

The vast majority of babies know when it’s time to be born based on their own physical and developmental readiness, so for this reason we encourage you to remember that a pregnancy is still classed as full term up to 42 weeks. Rest assured if you do go post-dates (as frustrating as it may be!), in a healthy pregnancy, you are giving your baby the best chance to be born happy and healthy and of course, less interventions for you too. Routine and unnecessary inductions only add to possible complications (including caesareans) and traumatic births.

Give your healthy, unborn baby a most precious gift of allowing him or her to arrive on their own birthday. Check out our article, 40 reasons to give your baby (at least!) 40 weeks, here.


First Day of Last Menstrual Period (LMP):
Cycle Length:
Defaults to an average of 28 days; please adjust if required.
Luteal Cycle:
Defaults to an average of 14 days; please adjust if required.

Kelly Winder is a birth attendant (aka doula), the creator of BellyBelly and mum to three beautiful children. Become a fan of BellyBelly on Facebook or add Kelly here. BellyBelly is also on Twitter. Please note that all of my suggestions and advice are of a generalised nature only and are not intended to replace advice from a qualified professional. BellyBelly.com.au – The Thinking Woman’s Website For Conception, Pregnancy, Birth and Baby.

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