Spotlight on pregnancy in women with diabetes

Recent studies looked at aspects of pregnancy in women with pre-existing type 1 or 2 diabetes, including rates of adverse outcomes, useful biomarkers, and typical dietary patterns.

Having a baby that is of large gestational age (LGA) is the most frequent complication of pregnancy in women with type 1 or type 2 diabetes, but a number of other issues are also common, according to a study published by The Lancet Diabetes & Endocrinology on Jan. 28. The British cohort study included 8,690 pregnancies in women with type 1 diabetes (median duration of diabetes, 13 years) and 8,685 in women with type 2 diabetes (median duration of diabetes, 3 years). Preterm delivery occurred in 42.5% and 23.4% of pregnancies, respectively. Rates of LGA birthweight were 52.2% and 26.2%, respectively. Prevalence of congenital anomalies and stillbirth was similar with either type of diabetes (44.8 vs. 40.5 per 1,000 and 10.4 vs. 13.5 per 1,000, respectively), but neonatal death was higher with type 2 diabetes (7.4 per vs. 11.2 per 1,000). Independent risk factors for perinatal death included having a third trimester HbA1c level of 6.5% or higher, being in the highest deprivation quintile, and having type 2 versus type 1 diabetes.

The authors noted that they identified maternal glycemia and body mass index as modifiable risk factors, highlighting the importance of dietary and psychosocial support. “Improving pregnancy outcomes is a shared challenge that requires better integration of diabetes health-care systems across primary care, paediatric and young adult clinics, and adult diabetes, obesity, and maternity services,” they wrote.

Traditional markers of glycemic control better predict obstetric and neonatal outcomes in pregnancies of women with type 1 diabetes than newer alternatives, according to a study published by Diabetes Care on Jan. 25. The secondary analysis of the Continuous Glucose Management (CGM) in Pregnant Women With Type 1 Diabetes Trial compared HbA1c levels, CGM data, and alternative biochemical markers (glycated CD59, 1,5-anhydroglucitol, fructosamine, glycated albumin) to predict pregnancy complications (preeclampsia, preterm delivery, LGA, neonatal hypoglycemia, admission to neonatal ICU). Time in the range of 63 to 140 mg/dL (3.5 to 7.8 mmol/L) and above 140 mg/dL (7.8 mmol/L) were the most consistently predictive CGM metrics, the authors found. They noted that HbA1c level was also a consistent predictor and that some of alternative laboratory markers “showed promise, but overall, they had lower predictive ability than HbA1c.”

Finally, pregnant women with type 1 diabetes eat an acceptable amount of carbohydrates but less fiber than recommended, according to a review published in the January Food Science & Nutrition. With a narrative literature search, researchers identified five observational studies with a total of 810 pregnant women with type 1 diabetes, which they compared to 15 studies with more than 100,000 pregnant women without diabetes. The women with diabetes had a mean total carbohydrate intake of 218 g/d, which was 20% lower than the average in women without diabetes but still within the acceptable range of 45% to 64% of energy intake. However, their mean intake of dietary fiber was lower than recommended for pregnant women regardless of presence of diabetes. The authors called for a focus on sufficient fiber intake and “additional studies of total carbohydrate intake including data on fiber and sugar intake with their relation to glycemic control and pregnancy outcome.”