Two-weekly self-monitoring of blood glucose okay for monitoring women with lifestyle-controlled gestational diabetes

In women with gestational diabetes mellitus (GDM) whose blood sugar is well controlled on a diet alone, the optimum SMBG frequency to control blood sugar is not established. University Malaya Medical Centre advised that SMBG should be less frequent than weekly for GDM patients. Self-monitoring blood glucose by finger-prick blood testing, usually four times daily, is recommended for controlling blood sugar in women with gestational diabetes.

Cheow Teng Thye, Universiti Malaya, Kuala Lumpur, Malaysia, and colleagues aimed to compare one day of four-point blood sugar monitoring every week to 1 day every two weeks, using HbA1c level as the marker of blood sugar control, which is an integrated measure of the average blood glucose level over the last 2-3 months.

The study included 104 patients with lifestyle-controlled gestational diabetes. They were randomized to 2-weekly or weekly 4-point per day (fasting on awakening and 2-h post-meals) SMBG. The primary outcome was the change in HbA1c levels from enrollment to 36 weeks of pregnancy across trial arms. The non-inferiority margin was an HbA1c rise of 0.2%.

The study revealed the following findings:

• The mean difference for change in HbA1c from enrollment to 36 weeks was 0.003%, within the 0.2% non-inferiority margin.
• The change in HbA1c level increased significantly within both trial arms—0.275% ± 0.241% in the 2-weekly arm versus 0.277% ± 0.236% in the weekly arm.
• Participants randomized to 2-weekly SMBG were significantly less likely to receive anti-glycemic treatment—9.6% versus 28.0% (relative risk 0.34).
• All secondary outcomes—maternal weight gain, preterm delivery, cesarean delivery, birthweight, and neonatal admission—were not significantly different.

The researchers conclude, "Two-weekly SMBG appeared adequate for monitoring women with lifestyle-controlled gestational diabetes."

Reference:

Thye, C. T., Hamdan, M., Sethi, N., Rajaratnam, R. K., Hong, J., & Tan, P. C. Self-monitoring of blood glucose two-weekly versus weekly in gestational diabetes on nutrition therapy: A randomized trial. International Journal of Gynecology & Obstetrics. https://doi.org/10.1002/ijgo.14861