A woman who has had recurrent miscarriages has five times the risk of a heart attack later on during her life, compared to women who never had a miscarriage, German researchers revealed in the medical journal Heart. Approximately up to 1 in every 5 pregnancies ends in miscarriage, the authors write; it is one of the most common pregnancy complications.

Dr Elham Kharazmi and team from the German Cancer Research Center, Division of Cancer Epidemiology, Heidelberg, Germany, say their findings are based on over 11,500 women who took part in the Heidelberg arm of EPIC (European Prospective Investigation into Cancer and Nutrition), a European study which is examining the effects of lifestyle and diet on cancer and other diseases.

All the 11,500 females had been pregnant at least once. The researchers focused on those who miscarried, had an abortion, or those whose babies had been stillborn.

25% (2,876) of all the women had had at least one miscarriage, 18% had had one or more abortions, and 2% had a stillborn baby.

Sixty-nine of the women had had at least three miscarriages; the researchers noticed they weighed more than the other women. There was a higher incidence of diabetes and hypertension among the women who had stillborn babies. Diabetes and hypertension (high blood pressure) are independent risk factors for stroke and heart disease.

112 women had a stroke and 82 a heart attack over a 10-year period.

The investigators were not able to link miscarriages, abortions or stillbirths to stroke risk. However, they did find clear associations between miscarriage, stillbirths and heart attack.

The women who had had more than three miscarriages were 9 times more likely to suffer a heart attack, compared to the other women. Those with one stillbirth or more had a 3.5 higher risk of heart attack.

After making adjustments for certain factors that also increase heart attack risk, such as alcohol intake, smoking status and body weight, the risk of heart attack among women with more than three miscarriages dropped to 5 times higher than other women.

They worked out that each miscarriage brought with it a 40% higher risk of heart attack.

The authors wrote: "These results suggest that women who experienced spontaneous pregnancy loss are at a substantially higher risk of (heart attack) later in life.

Recurrent miscarriage and stillbirth are strong gender predictors for (this) and thus should be considered as important indicators for monitoring cardiovascular risk factors and preventive measures." "Pregnancy loss and risk of cardiovascular disease: a prospective population-based cohort study (EPIC-Heidelberg)"
Elham Kharazmi, Laure Dossus, Sabine Rohrmann, Rudolf Kaaks
Heart doi:10.1136/hrt.2010.202226