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Clinical OpinionVolume 235, Issue 1p72-77July 2026

A proposed classification of diabetes mellitus in pregnancy

Rodney McLaren, Jr., MD 0000-0002-5013-3456
Correspondence
Corresponding author: Rodney McLaren Jr, MD.
Affiliations
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Maimonides Medical Center, Brooklyn, NY
a Send email to rmclaren@maimo.org
Sarah Crimmins, DO
Affiliations
Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Rochester Medical Center, Rochester, NY
b
Vincenzo Berghella, MD
Affiliations
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA
c
Janet Stein, MD, MS
Affiliations
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Maimonides Medical Center, Brooklyn, NY
a
Kavisha Khanuja, MD
Affiliations
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA
c
Affiliations & Notes
aDivision of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Maimonides Medical Center, Brooklyn, NY
bDepartment of Obstetrics, Gynecology, and Reproductive Sciences, University of Rochester Medical Center, Rochester, NY
cDivision of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA
Article Info
Publication History:
Received October 19, 2025; Revised January 16, 2026; Accepted January 28, 2026; Published online February 2, 2026
Footnotes:
The authors report no conflict of interest.
Copyright: © 2026 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
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Cover Image - American Journal of Obstetrics & Gynecology, Volume 235, Issue 1

Abstract

Pregnancies complicated by diabetes mellitus are at increased risk of adverse perinatal outcomes. The American College of Obstetricians and Gynecologists recommends universal screening for gestational diabetes mellitus during pregnancy at 24 to 28 weeks of gestation. However, there is controversy on the utility of screening or identification of patients with early gestational diabetes mellitus. In this clinical perspective, an evidence-based classification of diabetes in pregnancy (ie, diagnostic criteria for standard gestational diabetes mellitus vs early gestational diabetes mellitus vs pregestational diabetes mellitus) has been provided to help define subgroups along the spectrum of glucose intolerance/insulin resistance to inform future outcome-based studies.

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Key words

  1. diabetes mellitus
  2. diabetes of pregnancy
  3. gestational diabetes mellitus
  4. screening and diagnosis

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