Trying to figure out your chances of miscarrying? Sadly, you are going to have a hard time finding good information.
Many websites claim to tell you your risk of miscarriage, citing statistics that look like these:
But problems abound with their numbers.
Problem 1: These sites rarely provide their sources, so you cannot tell whether their information is reliable.
Problem 2: These sites do not breakdown miscarriage risk by other known risk factors, like the mother’s age.
Problem 3: Nearly all these sites derive their statistics from just two small studies, one which tracked 222 women from conception through just the first 6 weeks of pregnancy, and another which tracked 697 pregnancies, but only after a fetal heartbeat had been detected–a key point, because heartbeat detection dramatically lowers the chances of a miscarriage.
The lack of good information frustrated me when I was pregnant, and I bet it frustrates you too. So I have compiled a summary of the best research on risk of miscarriage. Where possible, I break down the risk by…
- pregnancy week
- before a heartbeat has been detected
- after a heartbeat has been detected
- fetal heart rate
- mother’s age
- father’s age
- number of prior miscarriages
Edit: I also have a new post on how morning sickness signals a lower risk.
Risk of Miscarriage by Pregnancy Week
Miscarriage risk drops as pregnancy progresses. The risk is highest early in the first trimester. Fortunately, for most women by 14 weeks their chance of a miscarriage is less than 1%.
Miscarriages rates declined between 6 to 10 weeks, according to a study of 697 pregnancies with a confirmed fetal heartbeat:
- 9.4% at 6 weeks
- 4.6% at 7 weeks
- 1.5% at 8 weeks
- 0.5% at 9 weeks
- 0.7% at 10 weeks
A similar study of 668 pregnancies with a confirmed fetal heartbeat between 6 and 10 weeks, found a similar decline in miscarriage risk by week:
- 10.3% at 6 weeks
- 7.9% at 7 weeks
- 7.4% at 8 weeks
- 3.1% at 9 weeks
But for women in their mid to late 30s and early 40s, these studies understate the risk. Even after confirmation of a fetal heartbeat, miscarriage risk remains high for women 40 and older through 12 weeks, according to a study of 384 women 35 and older.
Despite the higher risk for this age group overall, a normal ultrasound result from 7 weeks remains a promising sign. Women who entered the study in their 4th to 5th week of pregnancy had about a 35% risk of miscarriage. Women who entered the study later, and who therefore had a normal ultrasound and heartbeat at 7-10 weeks, had a risk under 10%.
Miscarriage Risk by Fetal Heart Rate
A fetal heartbeat often indicates a healthy, viable pregnancy. But a fetal heart rate that is too slow can instead signal an impending miscarriage.
The chance of a first trimester miscarriage varies by fetal heart rate, according to a study of 809 pregnancies. The lower the heart rate, the higher the miscarriage risk. (Normal fetal heart rates change with fetal age, so these tables break down the risk by pregnancy week.)
Up to 6 weeks 2 days gestation:
Between 6 weeks 3 days and 7 weeks 0 days:
After 7 weeks, the fetal heart rate was at or above 120 beats per minute for almost all ongoing pregnancies.
Miscarriage Risk by Week Before Confirmation of a Heartbeat
Many women will not have an ultrasound and fetal heartbeat confirmation until sometime between 8-10 weeks. What are their chances of a miscarriage before that crucial piece of news?
In a large prospective study of 4,887 women trying to conceive, 4070 became pregnant. Their rate of miscarriage was 4-5% in week 6. By week 7, this risk fell to 2.5%. Rates hovered around 2% per week until week 13, when chances of a miscarriage dipped below 1%
Personal Risk Factors
Your personal characteristics and behaviors alter your miscarriage risk. The most important risk factor, as is well known, is the woman’s age: Miscarriage rates climb as women age, especially after the late 30s. The man’s age matters too, especially after they turn 40.
Risk of Miscarriage by the Woman’s Age
Anne-Marie Nybo Anderson, of the Danish Epidemiology Science Centre led the largest population-based study ever conducted on age and miscarriage. Anderson tracked every “reproductive outcome”– every pregnancy, miscarriage, birth, stillbirth, or abortion–in Denmark between the years of 1978 and 1992–ultimately tracking outcomes of over a million pregnancies.
What did she find? Miscarriage risk rises sharply during a woman’s late 30s and reached nearly 100% by age 45.
Rates of ectopic pregnancy also rose with age:
As did the chances of a stillbirth:
(In Anderson’s study, stillbirth was defined as a loss after 28 weeks. In the U.S., any loss after 20 weeks is usually considered a stillbirth)
Take heart though: as scary as the rise in stillbirths sounds, the risk remains under 1% through age 45.
Anderson’s study’s findings parallel those of another large and well-studied sample: U.S. pregnancies conceived via IVF.
Just as in Anderson’s study of Danish pregnancies, the uptick in miscarriage risk among IVF pregnancies begins at age 38.
Intriguingly, the overall miscarriage rates among IVF pregnancies is lower than in the Denmark sample. This is probably due to selection effects. Only some women manage to become pregnant through IVF, and embryos transferred during IVF are chosen based on early signs of normal development. Passing through these early hurdles likely ups the odds of a successful pregnancy.
Risk of Miscarriage by the Man’s Age
Researchers often ignore the man’s age when studying miscarriage. Most women marry men who are about the same age, so researchers have trouble teasing apart the effects of the woman’s age from the man’s age.
Fortunately, several studies have now included couples in which either the woman or the man is much older than their partner.
These studies provide a clear and consistent picture: older prospective fathers raise the risk of miscarriage by about 25-50%. One study found an a 60% increase in the odds of a miscarriage if the father was over 40. Another reported a roughly 25% increase in the risk of miscarriage for fathers over the age of 35.
Other studies report similar effects; all showing most marked rise after age 40 (see here and here).
Risk by the Couple’s Combined Age
A young partner can offset some of your personal age-based miscarriage risk, especially if you are a man. Men whose partners are young, under 30, have relatively low chances of miscarriage regardless of their own age, according to large retrospective European study.
For women, alas, young partner only partially offset their age-based risk. Women over 35 with relatively young partners, under age 40, still face double to triple the odds of women in their 20s.
Older partners do, however, compound the risk for women in their 30s. A woman in her early 30s with a partner over 40 has roughly triple the odds of a woman with a partner the same age or younger.
Risk of Miscarriage After Confirmation of a Fetal Heartbeat for Older Women
On a more positive note, women in their late 30s and early 40s have a good chance of an ongoing pregnancy after confirmation of fetal heartbeat.
For women over 40, once a heartbeat has been detected at 7-10 weeks, the risk of a miscarriage falls to around 10%. After 20 weeks, the risk plummets to less than 1%.
How Does a Prior Miscarriage Affect Your Risk of Miscarriage?
Aside from age, the best predictor of whether a woman will miscarry is the number miscarriages she has already suffered. Most websites quote these statistics:
From these statistics, one prior miscarriage seems inconsequential; while just two prior miscarriages appears to dramatically raise your chances of another miscarriage.
Fortunately, these statistics are too dire for women who have had two prior miscarriages. The outcomes from a study over a million pregnancies paints a much more reassuring picture, at least for women who have had fewer than 3 prior miscarriages
Here’s the risk of a subsequent miscarriage for women who have never given birth before:
And for women who have given birth before:
The Bottom Line
In early pregnancy, miscarriage risk falls with each passing week, with significant drops around the 7-week mark, and again after the 12-week mark.
Your age, your partner’s age, and your number of prior miscarriages all affect your overall risk of miscarriage. Miscarriage risk rises dramatically after about age 37 for women, and age 40 for men.
References
Ammon Avalos, L., Galindo, C. and Li, D.-K. (2012), A systematic review to calculate background miscarriage rates using life table analysis. Birth Defects Research Part A: Clinical and Molecular Teratology, 94: 417–423. doi: 10.1002/bdra.23014
Cohen-Overbeek TE, Hop WC, den Ouden M, Pijpers L, Jahoda MG, Wladimiroff JW. Spontaneous abortion rate and advanced maternal age: consequences for prenatal diagnosis. Lancet. 1990 Jul 7;336(8706):27-9.
Doubilet PM, Benson CB. Embryonic heart rate in the early first trimester: what rate is normal? J Ultrasound Med. 1995 Jun;14(6):431-4.
Kleinhaus K, Perrin M, Friedlander Y, Paltiel O, Malaspina D, Harlap S. Paternal age and spontaneous abortion. Obstet Gynecol. 2006 Aug;108(2):369-77.
Makrydimas, G., Sebire, N. J., Lolis, D., Vlassis, N. and Nicolaides, K. H. (2003), Fetal loss following ultrasound diagnosis of a live fetus at 6–10 weeks of gestation. Ultrasound Obstet Gynecol, 22: 368–372. doi: 10.1002/uog.204
Mukherjee S, Velez Edwards DR, Baird DD, Savitz DA, Hartmann KE. Risk of miscarriage among black women and white women in a U.S. Prospective Cohort Study. Am J Epidemiol. 2013 Jun 1;177(11):1271-8. doi: 10.1093/aje/kws393.
de la Rochebrochard E, Thonneau P. Paternal age and maternal age are risk factors for miscarriage; results of a multicentre European study. Hum Reprod. 2002 Jun;17(6):1649-56
Slama R, Bouyer J, Windham G, Fenster L, Werwatz A, Swan SH. Influence of paternal age on the risk of spontaneous abortion. Am J Epidemiol. 2005 May 1;161(9):816-23.
Tong S, Kaur A, Walker SP, Bryant V, Onwude JL, Permezel M. Miscarriage risk for asymptomatic women after a normal first-trimester prenatal visit. Obstet Gynecol. 2008 Mar;111(3):710-4. doi: 10.1097/AOG.0b013e318163747c.
Wilcox AJ, Weinberg CR, O’Connor JF, Baird DD, Schlatterer JP, Canfield RE, Armstrong EG, Nisula BC. Incidence of early loss of pregnancy. N Engl J Med. 1988 Jul 28;319(4):189-94.
Thank you very much for your very complete list including all ages. I am 36, have a five year old and 8 year old, but have also had three miscarriages. Finding information for my situation (currently almost 8 weeks again), had been impossible and very stressful. I am glad to see from your info that even at my age, if I have a good ultrasound tomorrow, the odds of this baby surviving are much higher than I thought with my profile! Thank you again, this is really a blessing for us “older” ladies especially.
You’re very welcome! I’ll keep my fingers crossed that you get good news tomorrow.
Thank you very much. Excellent report !! Great compilation !!!
I stumbled across this just now while trying to research miscarriage with a friend…
Apologies, but your facts about age are outdated and use very old research and studies. While there is an increased risk for miscarriage in AMA pregnancies, there is now far more research done on a woman’s health and fitness level in association with her age. Age alone does not have the same risk level as it once was thought and updated studies and research is proving that many women in their late 30’s and early 40’s and beyond have healthy, low risk pregnancies. In the past there were fewer pregnancies that occurred at that age, and committed health and fitness lifestyles were not as common. Fast forward to today when many more women are delaying childbirth for various reasons, as well as living active, healthy lives with better access to prenatal care, information and guidance, as opposed to an acceptance of aging, poor diet, sacrificing all your time to your children etc….the list of socioeconomic and social determinants goes on and on… people used to think 40 was old, and now 40+ year olds are just entering their prime. Your chart about the risk of miscarriage at 45 years old nearing 100% is from a study from 1978-1992- there’s no way to argue that things haven’t changed since then. At that point in time in prenatal care they also told women not to elevate their heart rate or exercise…
Please don’t scare women in their late 30′ and 40’s into having a stressful pregnancy with outdated information.
Signed, a 40 year old woman, competitive endurance athlete, and person with 2 low risk pregnancies at ages 39 and 40 (will be 41 at time of second baby’s birth).
Also, I have a triathlete friend that gave birth to a healthy baby girl after a low risk pregnancy at almost 47.
Thank you so much for this. Its impossible to find accurate information. I’m 34 and 7 weeks pregnant with my first baby. Every twinge or pull or even sneeze I think is going to turn into a problem. Turns out I tested positive for something called Group B Strep too so I’m on antibiotics and this is something I carry on my body that I can pass on during delivery and it had some pretty awful illnesses for the baby if contacted. I’m trying so hard not to stress myself out, but it’s nearly impossible. At least here I see 7weeks is a good drop and that 34 isn’t necessarily a fertility death sentence. I wish all of you ladies luck and healthy pregnancies. Thanks again, so much for this easily readable, accurate information.
You need to delete this page. Your title is lies and miscarriage statistics, yet all you have on this page are these “damn miscarriage statistics”. Every case is different. For instance, you have “how does a prior miscarriage affect your risk”? So you have that 95-100% of women who have had 4 miscarriages have another miscarriage after their 4th? You basically made a page full of miscarriage statists that have no accuracy. Each pregnancy and case is so diverse there is really no way to put numbers on this type of thing. And for women out there that have had miscarriages, or fear miscarriages (just about every women) this website I’m sure just raised their anxiety ten-fold. So I hope you take this into account and get rid of these “lies”.
I disagree. Amy is a trained researcher who interprets the current scientific literature on miscarriage for us lay people who have a hard time understanding what the statistics mean. Yes, of course, every miscarriage is different and every woman is different which is why every woman who has had a miscarrige should talk to their own Dr about their own risks.
Keep in mind that just because you have had 4 miscarriages in a row, doesn’t mean you will have more- it just means that your chances without intervention aren’t good. I know women who have had 4 miscarriages in a row who went on to have 2 successful pregnancies after taking clomid and using progesterone suppositories. This is why working with a dorctor is so important.
Thank you! I agree. If you have had three or more miscarriages in a row, seeing a reproductive specialist is recommended.
Kathleen, your assertion is completely and utterly incorrect. It absolutely IS possible to “put numbers on this kind of thing”. That’s what epidemiology statistics are for. The researcher studies large groups and can then examine the actual outcomes for that group. With a large enough data-set, this can then be applied to other large groups. One can’t say what the outcome will be for an individual, but one can say that X members of a group of X size will statistically have a particular outcome. Pretty much every medical statistic works this way. Every cancer patient is unique, but it still possible to predict 5 year survival rates for certain cancers with a reasonable degree of accuracy. This is no different
I disagree as well. And women that are stressed have a CHOICE to read her information or not . She doesn’t need to desensitiZe her page or delete it because it doesn’t suit you.
Kathleen, I’m afraid you’re very mistaken. As a researcher I can attest to the utility of epidemiological research in determining rates of risk. Keep in mind these are rates of probability not a magic 8 ball perfectly determining the future of any single person’s pregnancy.
I agree. This article made me feel worse and I question its accuracy. I’ve read so many studies on miscarriage risk and each one contradicts the next. This article is more of the same. Just remember, your baby’s life is in God’s hands. It doesn’t have to be subject to statistics.
I never understand, when people say at “8 weeks” does this mean the start or the end of the 8th week? For example, I am now 7 weeks and 4 days so I would officially say that I am already in my 8th week? Is this correct?
He’s, it is super confusing and the terminology is all over the place. Here I use 8 weeks to mean 8 completed weeks.
This article does not address miscarriage rates for women over 40 who use donor eggs. The rates presented above look dire. The risk rises by 100% at age 45?? What if the pregnancy is achieved through donor eggs? The risk would be way lower. Are you saying women over 40 cannot physically carry a baby to term due to extremely high miscarriage risk? It’s not uncommon for women to give birth up until 50 or beyond. I would like to see clarification that the miscarriage rates for over-40 women is linked to the egg quality or age of the eggs, not her physical age.
Thanks for the comment. I intended this article for women who became pregnant with their own eggs, but you make a very legitimate point. The miscarriage rates for donor eggs are lower.
As a proxy, use the age of your donor.
I agree, the info on age is totally outdated.
This is sad as your study s show that at my age I shudnt be pregnant wow this helps so because I’m not being sick it’s bad and that I shud cut my losses did you not think to say that women don’t always have to be sick to keep their baby this is yes fact ? But hurt full to those who go on every word you have put sorry if people think I’m wrong but I just feel very scared now as I’m 6 was on thur and now the worry I will now face for the next few weeks is going to kill me thanks again plz don’t leave my comments I will be blocking this page as left me very sat and scared 😕😖😔😟
I’m 39, husband is 37. I’m 13 weeks pregnant and this article scared the hell out of me. Thanx a lot for making me think my ancient body is a HIGH RANKED fetus grave yard.. 🙁
Do NOT thing that. It’s not true. My mom had my brother after 35 and another son after 40. Your body is beautiful, strong and life-giving. You need to believe it, because it’s true.
Yes, your body is not as fertile as it used to be, but it is far, far from a graveyard. You have a body that can support and grow a child inside, from a single cell to a complete baby, with arms, legs, eyes, a heart, a smile, a whole world of wonder. It’s breath-taking, and it’s happening inside you right now. So take care of yourself and be kind to yourself. You’ll do amazing. 🙂
Had my first daughter at 37 and the second when I was 40. Did not have a single problem during pregnancies. My hubby one year older than me.
I recommend not reading a page about miscarriage statistics if you’re going to be afraid about having a miscarriage!! You were ASKING for anxiety!! That’s not just for you, that’s for every other woman on here complaining this page of upset them and now they have to block it. Well they knew what the Articles were about why did they read them??? I have had a miscarriage and I knew the numbers could be scary but she didn’t just pull them out of a hat!
Any idea of the evidence for miscarriage risk regarding twin pregnancies, or if these stats apply to twin pregnancies also?
These stats are only for singleton pregnancies. But, good point! I should try to do a post specific to twin pregnancies. Someday!
Probably hard to find since most miscarriages happen before you know they are twins. There would be no way to analyze.
Thanks. I’m 9 and a bit weeks, no ultrasound yet, 36 and with three previous live births (no miscarriages); nice to know that my odds are decent for a good outcome.
Thank you for this! As a researcher and newly pregnant mother-to-be I’ve found the endless mommy blogs and online resources horrendously patronizing, lacking any citations, and quite obviously misleading. This site and your piece are godsends.
Great article based on comprehensive study’s. ThaThank you for compiling. Lets just hope the stats work in our favour….
Comprehensive? The age studies are 20-40+ years old?!?
Thank you so much. As on over 40 pregant perosn, it’s so hard finding statistics that apply to me. Appreciate all you hard work pulling this together.
Thank you so much for this information! I am also a researcher and I always appreciate getting some real data. I’m 32 and had my first miscarriage two months ago at 5.5 weeks. I’m now 6 weeks 1 day and so nervous about losing another one. This really helped put things into perspective, at least statistically. Of course every person’s experience is different. But knowing the overall averages really helps put things into perspective. I have my first ultrasound on four days…hoping to hear that (fast!) heartbeat!
Thank you for doing all this research ❤
Thanks so much! This is a difficult and much neglected topic that we lack clarity on in both the scientific and cultural spheres. Fantastic job.
Great job on compiling all the data. I’m having a situation where I’m bleeding (dark red currently) so went to the E.R.. They did blood work and a transvaginal ultrasound, the blood work came back good and the ultrasound did also with a heartbeat of 167 bpm. They determined that I was between 7 and 8 weeks pregnant. The bleeding stopped the next day but came back the following day so went into the E.R. again. They didn’t do the ultrasound this time but they did do another blood test with the h.c.g. levels showing a slight drop (e.r. doc said around 140,000 to 120,000). As I’m all kinds of worried now and have been scouring the internet looking for stats that would help me understand my chances of this pregnancy still being viable, I’m coming to the conclusion there are none. So if you get the chance and feel up to it, if you could include a chart with complications factored in, I would be extremely grateful as I already am for what you have done.
Thank you for all your hard work on this! I believe another nightmare is missed miscarriage. I find more and more women have these. Also PCOS sufferers like myself have apparently higher changes of miscarriage according to some sources.
Funnily I find many women miscarriage because they lack adequate care from their doctors. I had to dictate mine what bloods I want to have. Progesterone & TSH was my pick at 4tt. My progesterone was fine( I was also using natural progesterone cream to boost it) but I just found out my TSH is slightly above the recommended level. I will talk to my doctor as soon as possible to have more testing done. Some women had multiple miscarriages and doctors are unwilling to offer them any additional testing. I find it very upsetting
Great job on compiling that info, however I couldn’t see the miscarriage rates in first pregnancy age <35 if a fetal heartbeat hasn’t been detected (as in, not yet had scan)
Hi,
Thank you so much for compiling this data and these statistics. I had a question about the term “weeks” used by each of the studies. Did the studies refer to “weeks” starting from the date of conception, or from the first day of your last cycle?
Thanks so much!
Thank you so much for this! I was looking for something a little more concrete than “after 6 weeks your chance of miscarriage reduces week by week”. So informative, thank you so much for doing this!
I’m now 10 weeks! This time there was a heartbeat at 7 weeks 4 days! I’m terrified not because of this study .. I lost identical twins about 8 and a half months ago .. I was told I had one baby no heartbeat I didn’t believe it so I went and got a few other opinions and that’s when they found baby A 👼🏼 baby B 👼🏼This study is kinda crazy to me because I lost them around the end of week 8 almost 9 so my odds were like a 0.5 😭 ? with my twins it sounds crazy but I felt everything! a double boop it was implantation or them splitting, them wiggling around and around week 7 I was having pain like back labor getting huge overnight day by day just big and I knew something was wrong the pain stopped I didn’t feel pregnant anymore I never spotted or bled my placenta measured at over 12 weeks when I lost them I was 8 weeks 😢 And did the pill thing lost them at home then a dnc or something like it
Thank you for writing this. It has been good for me to read. We had a miscarriage in ’16 at 11 weeks and are pregnant again, but we fear a 2nd miscarriage (we are in week 8). This shed a little light and relief to what we’ve been reading elsewhere. I am going to share this with my wife in hopes to put her mind a little more at ease as every day is a concern and every spotting pad she has is worry…
Thank you again.
This is such a great article! Thank you for the time you put into collecting reliable data. ❤
As someone that had a loss at 15 weeks, I found this post extremely valuable! A lot of posts are written by content writers that will say anything to come up with a few thousand words. Greatly appreciated!
Great article Amy! I am wondering if you (or anyone else) knows when these studies count missed miscarriages at: the estimated time of fetal death, or time of mmc discovery? Thanks!
I feel that there is no where in science that allows a 100% rate of anything. I am sure there are many women who have had 4 or more miscarriages and then gone onto deliver a healthy baby
Also with regards to the heart rate- surely it’s crazy to presume that every baby with a heart rate in week 6 or < 80 will end in miscarriage?
This article was so helpful!!!! I have had two miscarriages in the past and I’m now 5w5d pregnant. This article makes me both hopeful and encouraged. Thank you for such helpful information and providing a little bit of peace in quite emotional weeks for me. ❤️
I had a daughter. Four miscarriages (three of those missed miscarriages) over a three year period and then had a healthy baby boy. He was worth the wait and pain. I was 38 when he was born. He’s not 1. Hang in there and never give up hope!
Great article, extremely helpful, thank you!
This was very helpful! My only question is the miscarriage, is that in a row or total? I had a miscarriage, healthy pregnancy and baby girl now 3, then a miscarriage last year, and last month… I also did have a termination due to chromosomal abnormalities after healthy pregnancy. Would that count as anything?
Yes, it’s in a row. And having had a healthy pregnancy generally boosts your chances of having another.
Excellent article. I love the title. So much medical information is a lie or simply irrelevant. The other big problem in the case of miscarriages is how many go unreported. This is a difficult thing to quantify but I am sure it is a significant percentage.
Thank you so much. I’m so thankful to have found your article. This needs to be marked as most reliable and credible!