乌鸦传媒

Spontaneous abortion -- commonly known as miscarriage -- was linked to a higher risk for subsequent gestational diabetes, a retrospective cohort study found.

Among over 100,000 pregnant women, those who previously experienced a miscarriage had a 25% higher relative risk for developing gestational diabetes during a subsequent pregnancy (RR 1.25, 95% CI 1.18-1.31), reported Liping Jin, MD, of Tongji University in Shanghai, and colleagues in .

This association was number-dependent, the group noted, with women who experienced more miscarriages seeing successively higher relative risks for gestational diabetes:

• One spontaneous abortion: RR 1.18 (95% CI 1.11-1.26)
• Two spontaneous abortions: RR 1.41 (95% CI 1.27-1.57)
• Three or more spontaneous abortions: RR 1.43 (95% CI 1.22-1.67)

That being said, Jin's group did not find a significant link between intentionally induced abortions and risk of gestational diabetes.

"Spontaneous abortion is one of the most common adverse outcomes in early pregnancy," they pointed out, noting that about 30% of all pregnancies worldwide end this way.

This isn't the first study to identify this link, they added, as found an even higher risk for gestational diabetes tied to a history of miscarriage.

Although the exact reason behind this association hasn't been determined yet, Jin's group said the source could be oxidative stress and inflammation, which increases one's risk for cardiovascular and metabolic disease -- in this case, gestational diabetes.

Given the ballooning rate of diabetes worldwide, the researchers advised all pregnant women with a history of miscarriage -- and in particular those with recurrent spontaneous abortion -- to attend more antenatal visits in order to monitor blood glucose regularly. These women should also be mindful of healthy eating and engaging in regular exercise, the group recommended.

"Considering the short- and long-term adverse effects of gestational diabetes on both mothers and their offspring, our findings may also have potential public health implications," Jin's group noted.

A total of 102,259 women (mean age 30) who visited one of the largest prenatal healthcare tertiary care hospitals in Shanghai from 2014 to 2019 were included in the final analysis. Those with multiple pregnancies, a history of gestational diabetes, or chronic diseases like hypertension, diabetes, kidney disease, and thyroid dysfunction were excluded from the study.

About 14% of the cohort had experienced a spontaneous abortion, 17.5% had experienced an induced abortion, and 3.9% had experienced both.

All participants underwent a standard fasting oral glucose tolerance test at 24 to 28 weeks of gestation, and 11.9% of the cohort were diagnosed with gestational diabetes.

Among women without an abortion history, median fasting blood glucose levels were 77 mg/dL compared with 79 mg/dL for those with a history of any type of abortion.

One limitation to the study was that data on spontaneous abortion were self-reported; due to the sensitive nature of this topic, Jin and colleagues noted that this number could very well have been underestimated. There were also no data on the timing between experiencing a miscarriage and the subsequent diagnosis of gestational diabetes, which could be a topic for future study.

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