Pregnancy loss and risk of subsequent type 2 diabetes

By Rebecca Jenkins
Women who lose a pregnancy have a significantly increased risk of later developing type 2 diabetes, a case–control study suggests, with the risk rising with every pregnancy loss.

Using a Danish nationwide cohort, researchers identified 24,774 women born between 1957 and 1997 who were diagnosed with type 2 diabetes between 1977 and 2017 and matched them with 247,740 controls without diabetes.

Women who had ever been pregnant and lost a pregnancy were 18% more likely to go on to develop diabetes compared with women who had ever been pregnant and not lost a pregnancy, the analysis showed.

Women who had lost two pregnancies had a 38% increased risk of developing type 2 diabetes and this rose to 71% for women who had lost three or more pregnancies.

‘Future studies should explore whether this association is due to common background factors or whether prediabetic metabolic conditions are responsible for this association,’ the researchers wrote in Diabetologia.

‘A follow-up strategy using HbA1c measurements, similar to that used in women with gestational diabetes, could perhaps prove beneficial to women with ≥3 pregnancy losses,’ they wrote.

The association was robust when adjusted for obesity and gestational diabetes, the researchers noted, and it was strongest in predefined subgroups of women who had a high likelihood of euploid pregnancy losses and a suspected immunological aetiology behind their losses.

Professor Jeremy Oats, Professorial Fellow, Melbourne School of Population and Global Health, University of Melbourne and previous Secretary General of the International Association of Diabetes in Pregnancy Study Groups, called the Danish study intriguing and agreed it could be worth monitoring glucose intolerance in this population.

‘With the “epidemic” of diabetes we are experiencing with reports of about 30% of women in the reproductive age group in the US either having overt or prediabetes, a check for glucose intolerance using either fasting glucose or an HbA1c measurement can be justified and likely to be more productive than measuring vitamin D levels for example,’ he told Medicine Today.

Professor Oats sounded a note of caution about the accuracy of reporting of previous pregnancy loss, observing that it came from routinely collected past obstetric history data.

‘It is possible that women with diabetes or perceived to be at higher risk may have a more carefully documented past obstetric history,’ he said.
Diabetologia 2020; https://doi.org/10.1007/s00125-020-05154-z.