Antenatal Corticosteroids and Their Effects on Maternal Glycemic Status: A Prospective Observational Study From an Indian Tertiary Referral Center.

Background Antenatal corticosteroids prevent multiple fetal complications and improve overall neonatal survival but at the cost of adverse effects including maternal hyperglycemia. This study aimed to understand the effect of antenatal corticosteroids on maternal glycemic control. Methodology This prospective observational study included 93 pregnant women with singleton pregnancies between 32 and 37 weeks gestation admitted for potential preterm labor. We assessed their glucose tolerance and categorized 56 participants with normal glucose tolerance in group 1, while 37 who had diabetes mellitus (DM) were categorized in group 2. Of the women with DM, 30 had gestational diabetes mellitus and seven had pre-existing type 2 diabetes. Betamethasone was administered as per the standard of care, two doses of 12 mg each, 24 hours apart. To assess the effect of corticosteroids on maternal blood glucose control, we monitored capillary blood glucose levels at specific time intervals for three days following the steroid administration. Fasting and post-meal glucose levels were checked a week after the administration of the steroid therapy, and it was observed that participants from group 1 had developed steroid-related hyperglycemia. Blood glucose levels ≥140 mg/dL were considered significant hyperglycemia, while blood glucose levels ≥160 mg/dL were considered severe hyperglycemia. Following this observation, we documented any modifications in the diabetes management plan during or after the corticosteroid treatment, including medical nutrition therapy, addition of oral anti-diabetic medications, commencement of insulin, or increasing insulin dosage. Standard software programs such as Microsoft Excel and SPSS (IBM Corp., Armonk, NY, USA) were used to analyze the collected data, summarize the findings, and identify any statistically significant relationships between the variables descriptive and inferential statistics, respectively. Results Participants from both groups demonstrated worsening glycemia requiring treatment involving insulin, following corticosteroid administration. The percentages of significant hyperglycemic participants from groups 1 and 2 were 72% and 92%, respectively. Severe hyperglycemia was seen in 43% and 84% of the participants from groups 1 and 2, respectively. An intervention involving insulin administration was required by group 2 participants with pre-existing diabetes within six hours of steroid administration, followed by those with gestational diabetes requiring intervention within 12-24 hours, and by group 1 participants at 24-48 hours. One week after the administration of antenatal corticosteroids, hyperglycemia persisted in 20 (35.71%) of the 56 participants in group 1, of which six (30%) participants required insulin therapy. On the other hand, 18 (48.64%) participants from group 2 required additional insulin therapy after a week of administration of steroids when compared to pre-steroid administration status. Conclusions The findings of this study demonstrate that antenatal betamethasone therapy resulted in worsening hyperglycemia in most pregnant women, regardless of pre-existing glycemic status. These findings highlight the need for close monitoring of blood glucose levels and potential adjustments to medication regimens following antenatal betamethasone administration, irrespective of the pre-existing glycemic status.