Glycemic control may not improve outcomes in women with GDM and twin pregnancies

In a recent study conducted at a single tertiary center, maternal glycemic control and its complications in twin pregnancies complicated by gestational diabetes mellitus (GDM) was shown. The findings were published in American Journal of Obstetrics and Gynecology.

The study included 105 patients with GDM in a twin pregnancy and a matched control group of patients with twin pregnancies but without GDM, in a 1:3 ratio. Glycemic control was evaluated based on the proportion of fasting, postprandial, and overall glucose values within the target range. Good glycemic control was defined as a proportion of values within target above the 50th percentile.

The findings revealed that good glycemic control did not lead to a reduction in the risk of composite neonatal morbidity compared to suboptimal glycemic control. Surprisingly, it was observed that good glycemic control was associated with a higher risk of SGA infants when compared to non-GDM pregnancies, particularly in the subgroup of patients with mild GDM who were managed with dietary interventions.

Specifically, in diet-treated GDM pregnancies, the incidence of SGA infants was significantly higher in those with good glycemic control compared to suboptimal control. This association was evident for both SGA below the 10th centile and SGA below the 3rd centile. Conversely, the rate of SGA in GDM pregnancies with suboptimal control did not significantly differ from non-GDM pregnancies. Additionally, a left-shift of the distribution of birthweight centiles was observed in cases of diet-treated GDM with good glycemic control, while the distribution in pregnancies with suboptimal control was similar to that of non-GDM pregnancies.

These findings raise important questions regarding the applicability of glycemic targets and diagnostic criteria used in singleton pregnancies to twin pregnancies. It challenges the assumption that the same glycemic control guidelines can be applied universally, emphasizing the need for tailored approaches in the management of GDM in twin pregnancies. The study also highlights concerns of potential over diagnosis and overtreatment of GDM in twin pregnancies, which may inadvertently result in harm to neonates. While these results are preliminary and further research is warranted, they provide valuable insights for healthcare professionals involved in the care of twin pregnancies complicated by GDM.

Source:

Berezowsky, A., Ardestani, S., Hiersch, L., Shah, B. R., Berger, H., Halperin, I., Retnakaran, R., Barrett, J., & Melamed, N. (2023). Glycemic Control and Neonatal Outcomes in Twin Pregnancies with Gestational Diabetes. In American Journal of Obstetrics and Gynecology. Elsevier BV. https://doi.org/10.1016/j.ajog.2023.06.046