Repeat miscarriages linked to heart attacks, study suggests

Losing a pregnancy is a sharp reminder of how cruel nature can be. Miscarriage is something many women experience, yet few of us talk about. And the pain of loss can feel worse when—as is usually the case—you don't know why it happened.

It may be that either the sperm or egg had chromosomal defects, meaning the blueprint to continue building the baby simply wasn't there. That's probably the most common reason for early miscarriage, although there's no way of knowing which pregnancies ended for this reason.

But new research is making progress on understanding why some women repeatedly experience miscarriage. And while it may lead to new treatments, it also throws up some disturbing implications for their health.

But those factors also suggest that women who experience miscarriage or stillbirth may be at higher risk of cardiovascular disease. And a new study from Germany seems to confirm just that.

The headline figures from the study were alarming. Women who'd had more than three miscarriages were nine times more likely to have a heart attack, and women who'd had a stillbirth were three times more likely. One, two, or three miscarriages showed a slight increase in risk, although it was small enough that it could have been due to chance.

After the researchers adjusted their figures to take account of the women's general health and lifestyle—including whether they smoked, were overweight, how old they were, and what their cholesterol level was—the risk reduced slightly, to a five-fold increase for more than three miscarriages, and a two-fold increase for stillbirth. The overall risk of heart attacks for this group of women was also quite low, because they were relatively young (35 to 66). We don't know whether miscarriage and stillbirth would also affect the heart attack risk of older women.

But those are still significant increases in risk. While it seems unlikely that recurrent miscarriage or stillbirth directly cause heart attacks, it seems clear that something about women who've experienced these things is putting them at higher risk.

The researchers say that doctors should view recurrent miscarriage and stillbirth as independent risk factors for heart disease in women. This means they should consider these women at higher risk because of their experiences, independent of other factors such as cholesterol measurements. This may make a difference to whether women are prescribed drugs to protect the heart, such as statins or aspirin.

What you need to know. The heartbreak of pregnancy loss may not be confined to the emotions. If you've had repeated miscarriages or a stillbirth, you may be at increased risk of heart disease. Make sure your doctor knows about your pregnancy history when you are discussing your cardiovascular risk.

—Anna Sayburn, patient editor, BMJ Group

ConsumerReportsHealth.org has partnered with The BMJ Group to monitor the latest medical research and assess the evidence to help you decide which news you should use.

—Aaron Bailey