Daily odds of pregnancy miscarriage

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This can be an upsetting topic, but after passing a pregnancy test and facing so much uncertainty about my future I just wanted something to make me feel a little more... in control. For me, that's statistics. So based on some human embryo survival rates - overall and at 6, 8, and 10 weeks, I did some curve matching to calculate the risk of miscarriage at each day of an early pregnancy. The data here is based on a study of 600 women who were tested daily for pregnancy while trying to conceive, so early pregnancies were all evaluated for survival rate. The numbers are an estimate, but they're something.

The following dates are based on an estimated LMP of February 13th, 2015.

Change LMP:
Month Day Year
Date Progress Overall probability of miscarriage
Friday March 6th, 2015 3W, 0D 33%
Saturday March 7th, 2015 3W, 1D 32.9%
Sunday March 8th, 2015 3W, 2D 32.6%
Monday March 9th, 2015 3W, 3D 32%
Tuesday March 10th, 2015 3W, 4D 31.3%
Wednesday March 11th, 2015 3W, 5D 30.3%
Thursday March 12th, 2015 3W, 6D 29.2%
Friday March 13th, 2015 4W, 0D 28%
Saturday March 14th, 2015 4W, 1D 26.6%
Sunday March 15th, 2015 4W, 2D 25.2%
Monday March 16th, 2015 4W, 3D 23.6%
Tuesday March 17th, 2015 4W, 4D 22.1%
Wednesday March 18th, 2015 4W, 5D 20.5%
Thursday March 19th, 2015 4W, 6D 18.9%
Friday March 20th, 2015 5W, 0D 17.3%
Saturday March 21st, 2015 5W, 1D 15.8%
Sunday March 22nd, 2015 5W, 2D 14.4%
Monday March 23rd, 2015 5W, 3D 13%
Tuesday March 24th, 2015 5W, 4D 11.7%
Wednesday March 25th, 2015 5W, 5D 10.5%
Thursday March 26th, 2015 5W, 6D 9.4%
Friday March 27th, 2015 6W, 0D 8.4%
Saturday March 28th, 2015 6W, 1D 7.5%
Sunday March 29th, 2015 6W, 2D 6.6%
Monday March 30th, 2015 6W, 3D 5.9%
Tuesday March 31st, 2015 6W, 4D 5.3%
Wednesday April 1st, 2015 6W, 5D 4.7%
Thursday April 2nd, 2015 6W, 6D 4.3%
Friday April 3rd, 2015 7W, 0D 3.9%
Saturday April 4th, 2015 7W, 1D 3.5%
Sunday April 5th, 2015 7W, 2D 3.2%
Monday April 6th, 2015 7W, 3D 3%
Tuesday April 7th, 2015 7W, 4D 2.8%
Wednesday April 8th, 2015 7W, 5D 2.6%
Thursday April 9th, 2015 7W, 6D 2.5%
Friday April 10th, 2015 8W, 0D 2.4%
Saturday April 11th, 2015 8W, 1D 2.3%
Sunday April 12th, 2015 8W, 2D 2.2%
Monday April 13th, 2015 8W, 3D 2.2%
Tuesday April 14th, 2015 8W, 4D 2.1%
Wednesday April 15th, 2015 8W, 5D 2.1%
Thursday April 16th, 2015 8W, 6D 2.1%
Friday April 17th, 2015 9W, 0D 2.1%
Saturday April 18th, 2015 9W, 1D 2%
Sunday April 19th, 2015 9W, 2D 2%
Monday April 20th, 2015 9W, 3D 2%
Tuesday April 21st, 2015 9W, 4D 2%
Wednesday April 22nd, 2015 9W, 5D 2%
Thursday April 23rd, 2015 9W, 6D 2%
Friday April 24th, 2015 10W, 0D 2%
Saturday April 25th, 2015 10W, 1D 2%
Sunday April 26th, 2015 10W, 2D 2%
Monday April 27th, 2015 10W, 3D 2%
Tuesday April 28th, 2015 10W, 4D 2%
Wednesday April 29th, 2015 10W, 5D 2%
Thursday April 30th, 2015 10W, 6D 2%
Friday May 1st, 2015 11W, 0D 2%
Saturday May 2nd, 2015 11W, 1D 2%
Sunday May 3rd, 2015 11W, 2D 2%
Monday May 4th, 2015 11W, 3D 2%
Tuesday May 5th, 2015 11W, 4D 2%
Wednesday May 6th, 2015 11W, 5D 2%
Thursday May 7th, 2015 11W, 6D 2%
Friday May 8th, 2015 12W, 0D 2%
Saturday May 9th, 2015 12W, 1D 2%
Sunday May 10th, 2015 12W, 2D 2%
Monday May 11th, 2015 12W, 3D 2%
Tuesday May 12th, 2015 12W, 4D 2%
Wednesday May 13th, 2015 12W, 5D 2%
Thursday May 14th, 2015 12W, 6D 2%

Future probability of miscarriage at a given day

Notes and disclaimers

All numbers are estimates. If you have better research, drop me an e-mail (spacefem@spacefem.com).

I used information from two studies to make my assumptions: Wilcox AJ, Baird DD, Weinberg CR (1999). "Time of implantation of the conceptus and loss of pregnancy." and Wang X, Chen C, Wang L, Chen D, Guang W, French J (2003). "Conception, early pregnancy loss, and time to clinical pregnancy: a population-based prospective study.". I was not able to obtain full access to the second one, but based on citations I believe I had the numbers I needed for this.

The studies analyzed women who were trying to conceive for the first time.

There is a page of good studies here: https://sites.google.com/site/miscarriageresearch/miscarriage-general that compares risks based on age, whether you've heard a heartbeat, previous miscarriage, and hosts of other factors.

Charts are generated by flot.