Childbirth/conception

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Expert: - 6/3/2008


Question
My lmp was on August 25th. There are usually about 32 or 33 days from the first day of my period to the first day of the next period. I had sex on the 4th of September then I had sex again on the 8th of September. I had a positive home pregnancy test October 5th. They babys heart beat was visible October 10th. I heard the actual heart beat about 2 weeks later. My due date according to lmp was May 31. According to an ultrasound I was given a due date of June 6th by one doctor. The second doctor said June 9th according to a 20 week ultrasound. Its June 3rd I am still pregnant. Is it possible that I could have gotten pregnant after the 17th of September? Because I did have sex again somewhere between the 19th  of September and first of October.

Answer
Maria,

Let me start by saying that due dates are guesses at best. Only around 1% of all babies are actually born on their due date.

That being said, the first ultrasound you had was the most accurate indicator of your due date.  This is because fetal development rates are extremely similar through the first 10 weeks.  Then other factors such as genetics and nutrition come into play causing different rates of growth.

The due date by LMP also isn't accurate for you because you don't have a 28 day cycle.  Since your cycle is longer than that, you probably ovulate later, which would agree with the June 6th date.


So, don't worry that you haven't had your baby yet.  The average length of a first pregnancy is 41 weeks 1 day worldwide, so it could still be a while, or tomorrow;-)



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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