Childbirth/conception

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Expert: - 12/27/2008


Question
my last period started 21st of july. doctor has given me a due date of 4th of june which means my last period would have started 28th of august. my first scan on 27 of october showed i was 8 weeks 4 days which would mean my last period was 28th of august but my last period was definetly the 21st of july. my periods have always been irregular. when did i concieve could it be beginning of august or september? thanks for your help

Answer
Jemma,

You should ignore the date of your last period since your cycles are irregular.  Ovulation typically occurs about 14 days before your next period begins, which for women with irregular and/or long cycles can be hard to predict since the time of ovulation may vary each month.


Based on your ultrasound, which is the most accurate way to determine your due date and conception between 8-10 weeks gestation, you most likely conceived around Sept. 11.  Ultrasound at this stage isn't off by more than about 3 days in either direction, so it is the most reliable estimate of predicting your conception and due date, especially since your cycles are irregular.



Best,
Catherine

Childbirth

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Catherine Beier MS CBE

Expertise

I can provide evidence-based information and current research findings concerning childbirth and pregnancy. My specializations include natural childbirth, pregnancy and birth interventions, fetal positioning, labor induction, choosing a care provider, midwives, homebirth, unassisted birth, natural pain relief, medications in pregnancy and birth, informed consent, understanding the risks and benefits of childbirth choices, doulas, waterbirth, childbirth methods, childbirth education classes, cesarean section, and VBAC.

Experience

I have been a childbirth educator, mother, author, public speaker, researcher, and birth advocate for the past 9 years. I am also the author of Giving Birth Naturally, a site dedicated to natural childbirth and pregnancy information. I publish evidence-based articles on pregnancy, childbirth, newborn care, and post-partum care. I'm also a mother of three children, two daughters and one son all born naturally. To learn more about what normal birth looks like, view the natural childbirth video of my son being born at home unassisted.

Publications
My book, Birth Outside the Box, was published in 2007.

Education/Credentials
I hold a Master's degree in communication disorders with an emphasis in child development. I am also an independent childbirth educator.

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