Hypoglycemia in Pregnant Women with Type 1 Diabetes: Is It Inevitable?

Barak M. Rosenn; Jane C. Khoury; Francis Mimouni; Shelley Ehrlich; Menachem Miodovnik

doi:10.1055/a-2442-7305

American Journal of Perinatology, Table of Contents

Am J Perinatol 2025; 42(11): 1381-1388
DOI: 10.1055/a-2442-7305

Review Article

Hypoglycemia in Pregnant Women with Type 1 Diabetes: Is It Inevitable?

Authors

Barak M. Rosenn

¹Department of Obstetrics, Gynecology, and Reproductive Health, Rutgers New Jersey Medical School, Jersey City Medical Center, Jersey City, New Jersey
Jane C. Khoury

²Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio

³Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio

⁴Division of Endocrinology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
Francis Mimouni

⁵Department of Pediatrics and Research Institute, Leumit Health Services, and the Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
Shelley Ehrlich

²Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio

³Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio

⁶Department of Environmental and Public Health Sciences, University of Cincinnati, College of Medicine, Cincinnati, Ohio
Menachem Miodovnik

⁷Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Inova Health System, Fairfax, Virginia

Abstract

The human body has abundant mechanisms to counteract hypoglycemia and prevent neuroglycopenia primarily involving the secretion of glucagon and adrenalin. Within several years from the onset of diabetes, people with type 1 diabetes lose their ability to mount a counterregulatory response to hypoglycemia and develop hypoglycemia unawareness, thus being at risk for deteriorating to a state of severe hypoglycemia and neuroglycopenia. Pregnant individuals with type 1 diabetes are particularly prone to experience severe hypoglycemia during the first half of pregnancy. This may be not only due to the institution of strict glycemic control and the nausea and vomiting prevalent during the early months of pregnancy, but also because the counterregulatory responses are further diminished during pregnancy. Severe hypoglycemia during early pregnancy does not appear to increase the risks of spontaneous abortion or congenital fetal malformations, but the potential long-term effects on the fetus are unknown. Recent technological advances have contributed to improved glycemic control and time in range as well as decreased risk of hypoglycemia in people with diabetes. These advances include treatment with insulin analogs, use of continuous glucose monitors, and closed-loop systems for administration of insulin. Limited studies have demonstrated that pregnant individuals with type 1 diabetes may also benefit from these modalities. While ongoing research continues to explore the adjustment of closed-loop systems for optimal use during pregnancy, more effort is needed to explore the optimal use of these modalities in pregnancy.

Key Points

People with type 1 diabetes have diminished counterregulatory responses to hypoglycemia and frequently develop hypoglycemia unawareness.
Pregnant individuals with type 1 diabetes are at increased risk for severe hypoglycemia particularly during the first half of pregnancy.
Use of insulin analogs and newer technologies for insulin administration may lower the risk of hypoglycemia in pregnant individuals with type 1 diabetes.

Keywords

hypoglycemia - diabetes - type 1 diabetes - counterregulatory hormones

Full Text

References

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