Summary

Background:

The prevalence of pregestational diabetes mellitus (PGDM) in women of reproductive age has surged globally, contributing to increased rates of adverse pregnancy outcomes. Hemoglobin A1c (HbA1c) is a crucial marker for diagnosing and monitoring PGDM, with periconceptional levels influencing the risk of congenital anomalies and complications.

Objectives:

To evaluate the association between periconceptional HbA1c levels and perinatal complications in pregnant women with poorly controlled PGDM.

Methods:

We conducted a retrospective analysis of prospectively collected data of pregnancies between 2010 and 2019, HbA1c > 6% at 3 months prior to conception or during the first trimester. Outcomes of periconceptional HbA1c levels were compared.

Results:

The cohort included 89 women: 49 with HbA1c 6–8%, 29 with HbA1c 8–10%, and 11 with HbA1c > 10%. Higher HbA1c levels were more prevalent in type 1 diabetics and were associated with increased end-organ damage risk. Women with elevated HbA1c levels tended toward unbalanced glucose levels during pregnancy. The cohort exhibited high rates of preterm delivery, hypertensive disorders, cesarean delivery, and neonatal intensive care unit admission. Overall live birth rate was 83%. While a significant correlation was found between HbA1c levels and preterm delivery, no consistent association was observed with other adverse outcomes.

Conclusions:

Periconceptional glycemic control in PGDM pregnancies is important. Elevated HbA1c levels are associated with increased risks of adverse outcomes. Beyond a certain HbA1c level, risks of complications may not proportionally escalate.