Pregnancy loss and recurrent pregnancy losses are strongly and consistently associated with an increased risk for later type 2 diabetes (T2D), according to study results published in Diabetologia.1
Pregnancy loss was previously found to be associated with later atherosclerotic disease and ischemic heart failure, and a recent prospective study2 revealed an association between pregnancy loss and later maternal T2D. The goal of the current study was to explore the association between pregnancy loss and recurrent pregnancy loss and T2D.
The study cohort included 24,774 individuals from a Danish nationwide cohort that included women diagnosed with T2D between 1977 and 2017. For each case, the researchers included 10 randomly selected control individuals without T2D from the Danish general population who were matched for educational level and birth year.
Of 24,774 women with T2D, 3227 (19.1%) had 1 pregnancy loss, 729 (4.3%) had 2 pregnancy losses, and 358 (2.1%) had ≥3 pregnancy losses. Of 247,740 control individuals, 31,144 (16.8%), 5981 (3.2%), and 2402 (1.3%) had 1, 2 and ≥3 pregnancy losses, respectively.
The risk for T2D was higher for women with a history of pregnancy loss and increased further for those with recurrent pregnancy loss. Compared with ever-pregnant women without pregnancy losses, the odds ratios for later T2D were 1.18 (95% CI, 1.13-1.23) for women with 1 pregnancy loss, 1.38 (95% CI, 1.27-1.49) for those with 2 pregnancy losses, and 1.71 (95% CI, 1.53-1.92) for those with ≥3 pregnancy losses.
Women who had never achieved a pregnancy had an odds ratio for T2D of 1.56 (95% CI, 1.51-1.61) compared with ever-pregnant women with any number of losses.
Pregnancy loss remained a significant risk factor for later T2D after adjustment for gestational diabetes and obesity. The researchers noted that the observed association was strongest in women with increased likelihood of euploid pregnancy loss and a suspected immunologic etiology behind their losses.
The study had several limitations, including those associated with the case-control epidemiologic design and potential missed diagnoses of pregnancy losses not treated in the hospital or very early losses.
“Whether metabolic conditions at the time of pregnancy loss explain the association with type 2 diabetes or the association is caused by a shared [etiology] need to be explored in future studies,” wrote the researchers.
Disclosure: This study was supported in part by Novo Nordisk. Please see the original reference for a full list of authors’ disclosures.
1. Egerup P, Mikkelsen AP, Kolte AM, et al. Pregnancy loss is associated with type 2 diabetes: a nationwide case-control study [published online May 19, 2020]. Diabetologia. doi:10.1007/s00125-020-05154-z
2. Horn J, Tanz LJ, Stuart JJ, et al. Early or late pregnancy loss and development of clinical cardiovascular disease risk factors: a prospective cohort study. BJOG. 2019;126(1):33-42.