Gestational Diabetes Risk Increases With History of Spontaneous Abortion

Women with a history of spontaneous abortion (SAB) were associated with an increased risk of gestational diabetes in later pregnancies, according to new findings.

Data from a recent study show pregnant women who experienced only spontaneous abortion or both spontaneous abortion and induced abortion were at higher risk of developing gestational diabetes, although no association between the history of induced abortion and gestational diabetes was observed.

As one of the most common complications of pregnancy, gestational diabetes has raised concerns with both adverse perinatal outcomes and increased long-term cardiovascular and metabolic health risk in mothers and their offspring.

Data show up to 30% of all pregnancies terminate in spontaneous aboriton, which has been associated with later maternal risk of cardiovascular disease, venous thromboembolism, and type 2 diabetes.

The current retrospective study examined the association between abortion history and the subsquent risk of gestational diabetes in a cohort of pregnant women at a tertiary care hospital in Shanghai, China. The patients visited the clinic on a regular basis from January 2014 - December 2019.

Investigators reviewed 125,430 pregnant women’s medical records and those with complete medical records and underwent a standard oral glucose tolerance test (OGTT) at 24 - 28 gestational weeks were included in the study for a total of 109,263 women. Women were categorized if they experienced only spontaneous abortion, only induced abortion, or both spontaneous and induced abortion.

The study outcomes of interest was gestational diabetes diagnosed with a 75-g OGTT and based on the following criteria

• Fasting blood glucose levels ≥92 mg/dL
• 1-hour blood glucose levels ≥180 mg/dL
• 2-hour blood glucose levels ≥153 mg/dL

In analysis, a multivariable-adjusted log-binomial analysis was used to estimate the relative risk (RR) and 95% CI for the association of different types of abortion with incidence GD.

From the population of 102,259 women (mean age, 29.8 years), 14,579 (14.3%) experienced only spontaneous abortion, 17,935 (17.5%) experienced only induced abortion, and 4017 (3.9%) experienced both.

From OGTT, investigators identified 12,153 cases of gestational diabetes, for a prevalence of 11.9% in the cohort. The corresponding prevalence of gestational diabetes was

• 10.7% (7018 of 65 728 women) in the no abortion history group
• 15.7% (2282 of 14 579 women) in the spontaneous abortion only group
• 12.3% (2213 of 17 935 women) in the induced abortion group
• 15.9% (640 of 4017 women) in the both spontaneous and induced abortion group

In comparison to those with no abortion history, the risk of gestational diabetes increased by 25% (RR, 1.25; 95% CI, 1.18 - 1.31) for preganant women who experienced only spontaneous abortion and by 15% (RR, 1.15; 95% CI, 1.05 - 1.27) for pregnant women who experienced both spontaneous and induced abortion.

Data show the RR for gestational diabetes increased by 18% (RR, 1.18; 95% CI, 1.11 - 1.26) for pregnant women with 1 spontaneous abortion, by 41% (RR, 1.41; 95% CI, 1.27 - 1.57) for those with two, and by 43% (RR, 1.43; 95% CI, 1.22 - 1.67) for those with more than two.

“Our findings suggest that pregnant women with a history of SAB, especially those with a history of recurrent SAB, should attend more antenatal visits to monitor their blood glucose and implement early prevention and intervention (eg, eating more healthfully and doing regular physical activity),” wrote lead investigator Liping Jin, MD, Shanghai Key Laboratory of Maternal Fetal Medicine, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University.

The study, “Association of History of Spontaneous or Induced Abortion With Subsequent Risk of Gestational Diabetes,” was published in JAMA Network Open.