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 August 10th, 2020.

Change LMP:
Month Day Year
Date Progress Overall probability of miscarriage
Monday August 31st, 2020 3W, 0D 33%
Tuesday September 1st, 2020 3W, 1D 32.9%
Wednesday September 2nd, 2020 3W, 2D 32.6%
Thursday September 3rd, 2020 3W, 3D 32%
Friday September 4th, 2020 3W, 4D 31.3%
Saturday September 5th, 2020 3W, 5D 30.3%
Sunday September 6th, 2020 3W, 6D 29.2%
Monday September 7th, 2020 4W, 0D 28%
Tuesday September 8th, 2020 4W, 1D 26.6%
Wednesday September 9th, 2020 4W, 2D 25.2%
Thursday September 10th, 2020 4W, 3D 23.6%
Friday September 11th, 2020 4W, 4D 22.1%
Saturday September 12th, 2020 4W, 5D 20.5%
Sunday September 13th, 2020 4W, 6D 18.9%
Monday September 14th, 2020 5W, 0D 17.3%
Tuesday September 15th, 2020 5W, 1D 15.8%
Wednesday September 16th, 2020 5W, 2D 14.4%
Thursday September 17th, 2020 5W, 3D 13%
Friday September 18th, 2020 5W, 4D 11.7%
Saturday September 19th, 2020 5W, 5D 10.5%
Sunday September 20th, 2020 5W, 6D 9.4%
Monday September 21st, 2020 6W, 0D 8.4%
Tuesday September 22nd, 2020 6W, 1D 7.5%
Wednesday September 23rd, 2020 6W, 2D 6.6%
Thursday September 24th, 2020 6W, 3D 5.9%
Friday September 25th, 2020 6W, 4D 5.3%
Saturday September 26th, 2020 6W, 5D 4.7%
Sunday September 27th, 2020 6W, 6D 4.3%
Monday September 28th, 2020 7W, 0D 3.9%
Tuesday September 29th, 2020 7W, 1D 3.5%
Wednesday September 30th, 2020 7W, 2D 3.2%
Thursday October 1st, 2020 7W, 3D 3%
Friday October 2nd, 2020 7W, 4D 2.8%
Saturday October 3rd, 2020 7W, 5D 2.6%
Sunday October 4th, 2020 7W, 6D 2.5%
Monday October 5th, 2020 8W, 0D 2.4%
Tuesday October 6th, 2020 8W, 1D 2.3%
Wednesday October 7th, 2020 8W, 2D 2.2%
Thursday October 8th, 2020 8W, 3D 2.2%
Friday October 9th, 2020 8W, 4D 2.1%
Saturday October 10th, 2020 8W, 5D 2.1%
Sunday October 11th, 2020 8W, 6D 2.1%
Monday October 12th, 2020 9W, 0D 2.1%
Tuesday October 13th, 2020 9W, 1D 2%
Wednesday October 14th, 2020 9W, 2D 2%
Thursday October 15th, 2020 9W, 3D 2%
Friday October 16th, 2020 9W, 4D 2%
Saturday October 17th, 2020 9W, 5D 2%
Sunday October 18th, 2020 9W, 6D 2%
Monday October 19th, 2020 10W, 0D 2%
Tuesday October 20th, 2020 10W, 1D 2%
Wednesday October 21st, 2020 10W, 2D 2%
Thursday October 22nd, 2020 10W, 3D 2%
Friday October 23rd, 2020 10W, 4D 2%
Saturday October 24th, 2020 10W, 5D 2%
Sunday October 25th, 2020 10W, 6D 2%
Monday October 26th, 2020 11W, 0D 2%
Tuesday October 27th, 2020 11W, 1D 2%
Wednesday October 28th, 2020 11W, 2D 2%
Thursday October 29th, 2020 11W, 3D 2%
Friday October 30th, 2020 11W, 4D 2%
Saturday October 31st, 2020 11W, 5D 2%
Sunday November 1st, 2020 11W, 6D 2%
Monday November 2nd, 2020 12W, 0D 2%
Tuesday November 3rd, 2020 12W, 1D 2%
Wednesday November 4th, 2020 12W, 2D 2%
Thursday November 5th, 2020 12W, 3D 2%
Friday November 6th, 2020 12W, 4D 2%
Saturday November 7th, 2020 12W, 5D 2%
Sunday November 8th, 2020 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.