San Francisco — A new joint clinical practice guideline (CPG) from two endocrinology societies addresses managing preexisting diabetes and pregnancy, starting with a call to screen for pregnancy intention at every clinical encounter.
“The lack of preconception care for patients with preexisting diabetes is a major focus of this guideline. We know from strong meta-analyses that there is a significant reduction in poor pregnancy outcomes with good preconception care ahead of time. There’s a 71% reduction in congenital malformations and reductions in perinatal mortality as well as other negative outcomes. And so, it’s really important to have preconception care,” Jennifer A. Wyckoff, MD, CPG writing chair and clinical professor of internal medicine at the University of Michigan, Ann Arbor, Michigan, told Medscape Medical News.
“Preexisting Diabetes and Pregnancy: An Endocrine Society and European Society of Endocrinology Joint Clinical Practice Guideline,” was presented on July 13, 2025, at ENDO 2025: The Endocrine Society Annual Meeting, and was simultaneously published in the Journal of Clinical Endocrinology and Metabolism.
Cosponsoring the CPG are the Association of Diabetes Care and Education Specialists, the American Pharmacists Association, and the European Association for the Study of Diabetes. It is supported by the Society for Maternal-Fetal Medicine, while the American College of Obstetricians and Gynecologists was a participating organization.
The CPG provides 10 clinical recommendations, covering preconception, pregnancy, labor and delivery, and postpartum care for women with both type 1 diabetes (T1D) and type 2 diabetes (T2D). It was written by a multidisciplinary panel working with a noteworthy absence of data in most areas.
“There are not a lot of randomized controlled trials in diabetes in pregnancy, so there’s not a lot of high-quality data. For this particular guideline, there are no strong recommendations. There are only conditional recommendations worded as ‘suggestions.’…This serves to highlight some of the areas where research is most needed,” said Wyckoff.
The CPG makes the following conditional recommendations:
- For women with T1D or T2D who have the possibility of becoming pregnant, the CPG suggests that they be asked about pregnancy intention at every medical encounter, including primary care, reproductive, and endocrinology, as well as emergency/urgent care when appropriate. This was based on indirect evidence of the strong association between preconception care and reduced glycated hemoglobin and congenital malformations, Wyckoff said in her presentation.
- In those with diabetes capable of becoming pregnant, contraception use when pregnancy is not desired is suggested.
- For those with T2D, the suggestion is to discontinue GLP-1 use before conception, rather than between the start of pregnancy and the end of the first trimester. This is in line with the manufacturer’s labeling and is based on limited data of exposure risk during pregnancy. But regardless of when the GLP-1 is discontinued, active glycemic management is needed afterward.
- For those with T2D already on insulin, the panel suggested against the routine addition of metformin, based on the writing panel’s judgment that the benefit of adding metformin doesn’t outweigh the potential harm.
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The recommendation regarding consumption of > 175 g or < 175 g of carbohydrates per day was made as an “either/or” due to inadequate evidence for or against.
“We had very little data on nutrition…There are data suggesting that extremes of carbohydrate intake, either far too much carbohydrate or far too little carbohydrate, are detrimental. Less than 100 grams of carbs a day would be detrimental. But there is nothing to really clarify what the correct amount should be. It’s quite complex, because it also depends on the individual woman, on her BMI, activity level, and other macronutrients in her diet,” Wyckoff told Medscape Medical News.
- Another either/or suggestion was made for continuous glucose monitoring (CGM) use or fingerstick blood glucose monitoring in those with T2D, given the lack of direct evidence for superiority. (Other guidelines strongly recommend CGM use for T1D, but that wasn’t one of the questions addressed in the current CPG.)
- For those who are using a CGM, the CPG suggests against the use of a single 24-hour CGM target of < 140 mg/dL in place of standard of care pregnancy glucose targets of < 95 mg/dL, 1-hour postprandial < 140 mg/dL, and 2-hour postprandial < 120 mg/dL. However, clinicians should be aware that not all hybrid closed-loop system algorithms can meet those targets.
- For those with T1D who are pregnant, the use of a hybrid closed-loop insulin delivery system is suggested, rather than separate noncommunicating pump and CGM devices or multiple daily injections.
- Early delivery is suggested, based on risk assessment rather than expectant management. This is based on indirect evidence that risks may outweigh the benefits of expectant management beyond 38 weeks gestation and that risk assessment criteria could be useful to inform ideal delivery timing. “It is very difficult to construct strong research studies around timing of delivery,” Wyckoff noted.
- Postpartum endocrine care is suggested in addition to usual obstetric care, based on indirect evidence. “In the postpartum period, there is often a relapse in care. We emphasize that the postpartum is often preconception for the next pregnancy so that intrapartum care is important. We hope to bring attention to that through this guideline,” she said.
Asked to comment, Camille E. Powe, MD, co-director of Diabetes in Pregnancy Programs at Massachusetts General Hospital and Massachusetts General Brigham, Boston, told Medscape Medical News, “The Endocrine Society guideline answered 10 specific important questions for the management of preexisting diabetes in pregnancy, some of which are very controversial and things that clinicians really want to know about. I applaud them for addressing the questions very specifically, with rigor and evidence.”
Powe, who works with the American Diabetes Association (ADA) in several capacities related to diabetes in pregnancy but was not officially speaking for the ADA, noted that this CPG generally aligns with the ADA’s guidance on preexisting diabetes in pregnancy published as a section of its annual Standards of Care, although the CPG goes into more detail with some of the specific recommendations.
“Historically, pregnant women have not been included in clinical research, and we are still dealing with the implications of that. It’s done for good intentions, but I think the unintended consequences of not including pregnant and lactating women in research is that then we have less of an evidence base for which we can treat our pregnant and lactating patients,” Powe noted.
She said the writing panel’s inability to make strong recommendations “speaks to the incredible need for high-quality evidence generation in pregnancy and postpartum for those living with diabetes. It’s really a call to action for scientists, investigators, physicians, funders, and industry partners to do this work because we really should have the evidence in women’s health research to support high-quality care of people with diabetes in pregnancy.”
Wyckoff reported no disclosures. Powe is an associate editor for the ADA journal Diabetes Care and received research support from Dexcom.
Miriam E. Tucker is a freelance journalist based in the Washington, DC area. She is a regular contributor to Medscape Medical News, with other works appearing in The Washington Post, NPR’s Shots blog, and Diatribe. She can be found on X @MiriamETucker and on BlueSky @miriametucker.bsky.social.