Updated December 10, 2014.
Question: When Do Most Miscarriages Occur?
Many women wonder at what point in pregnancy they will be able to breathe a sigh of relief and stop worrying so much about miscarriages.
Answer:
Pregnancy is obviously a time of anxiety as well as anticipation, and a lot of pregnant women worry -- especially those who have had a miscarriage before. Some seek comfort in statistics, feeling a greater sense of relief after passing specific milestones in pregnancy at which statistical odds of miscarriage decrease.
If you search for information on miscarriage statistics, you will find a wide range -- different sources claim that anywhere from 10 to 75% of conceptions end in miscarriage.
The top of that range sounds scarier than it is; the 75% number is speculated on the number of fertilized eggs that may pass through the woman's body without implanting.
By the time you actually get a positive pregnancy test, your risk of miscarriage will be at the lower end of that range. In a 1988 study, researchers followed 221 women over a combined total of 707 menstrual cycles, with 198 total pregnancies. They found that 22% of the pregnancies ended before they could be detected clinically (such as by standard urine pregnancy tests). The total miscarriage rate was 31% (including the early miscarriages).
Most cited references estimate that anywhere between 10 and 25% of clinically recognized pregnancies will end in miscarriage.
Risk of miscarriage drops significantly after a doctor detects a heartbeat on ultrasound.
As pregnancy progresses, miscarriage risk decreases. Most estimates state that 80% of miscarriages happen before 12 weeks of pregnancy.
Because 80% of miscarriages happen in the first trimester, the overall risk of miscarriage after the first trimester is about 3%.
Most pregnancy losses after 20 weeks are classified in one of two ways -- either a stillbirth, or a neonatal death (if the baby is born alive, but passes away within the first month of life). Risk for both stillbirth and neonatal death is about 1 in 200.
Sources:
National Center for Health Statistics, "Health, United States 2005." Accessed 8 Feb 2008.
Tulandi, Togas, "Patient information: Miscarriage." UpToDate Patient Information. Aug 2007. Accessed 8 Feb 2008.
Wilcox, A.J., C.R. Weinberg, J.F. O'Connor, D.D. Baird, J.P. Schlatterer, R.E. Canfield, E.G. Armstrong, and B.C. Nisula, "Incidence of Early Loss of Pregnancy." New England Journal of Medicine 1988. Accessed 8 Feb 2008.
Question: When Do Most Miscarriages Occur?
Many women wonder at what point in pregnancy they will be able to breathe a sigh of relief and stop worrying so much about miscarriages.
Answer:
Pregnancy is obviously a time of anxiety as well as anticipation, and a lot of pregnant women worry -- especially those who have had a miscarriage before. Some seek comfort in statistics, feeling a greater sense of relief after passing specific milestones in pregnancy at which statistical odds of miscarriage decrease.
Overall Miscarriages
If you search for information on miscarriage statistics, you will find a wide range -- different sources claim that anywhere from 10 to 75% of conceptions end in miscarriage.
The top of that range sounds scarier than it is; the 75% number is speculated on the number of fertilized eggs that may pass through the woman's body without implanting.
By the time you actually get a positive pregnancy test, your risk of miscarriage will be at the lower end of that range. In a 1988 study, researchers followed 221 women over a combined total of 707 menstrual cycles, with 198 total pregnancies. They found that 22% of the pregnancies ended before they could be detected clinically (such as by standard urine pregnancy tests). The total miscarriage rate was 31% (including the early miscarriages).
Most cited references estimate that anywhere between 10 and 25% of clinically recognized pregnancies will end in miscarriage.
Risk of miscarriage drops significantly after a doctor detects a heartbeat on ultrasound.
Pregnancy Loss Rates by Trimester
As pregnancy progresses, miscarriage risk decreases. Most estimates state that 80% of miscarriages happen before 12 weeks of pregnancy.
Because 80% of miscarriages happen in the first trimester, the overall risk of miscarriage after the first trimester is about 3%.
Most pregnancy losses after 20 weeks are classified in one of two ways -- either a stillbirth, or a neonatal death (if the baby is born alive, but passes away within the first month of life). Risk for both stillbirth and neonatal death is about 1 in 200.
Sources:
National Center for Health Statistics, "Health, United States 2005." Accessed 8 Feb 2008.
Tulandi, Togas, "Patient information: Miscarriage." UpToDate Patient Information. Aug 2007. Accessed 8 Feb 2008.
Wilcox, A.J., C.R. Weinberg, J.F. O'Connor, D.D. Baird, J.P. Schlatterer, R.E. Canfield, E.G. Armstrong, and B.C. Nisula, "Incidence of Early Loss of Pregnancy." New England Journal of Medicine 1988. Accessed 8 Feb 2008.