Preexisting Diabetes in Pregnancy

Full Guideline: Preexisting Diabetes and Pregnancy: An Endocrine Society and European Society of Endocrinology Joint Clinical Practice Guideline 

JCEM | July 2025 (online July 2025) 

Jennifer A. Wyckoff (Chair), Annunziata Lapolla (Co-Chair), Bernadette D. Asias-Dinh, Linda A. Barbour, Florence M. Brown, Patrick M. Catalano, Rosa Corcoy, Gian Carlo Di Renzo, Nancy Drobycki, Alexandra Kautzky-Willer, M. Hassan Murad, Melanie Stephenson-Gray, Adam G. Tabák, Emily Weatherup, Chloe Zera. Naykky Singh-OspinaShape 

A Systematic Review Supporting the Endocrine Society Clinical Practice Guidelines on the Management of Preexisting Diabetes in Pregnancy [LINK COMING; PLEASE LINK THIS WHOLE TITLE] 

Resources 

• Clinician Education Presentation (Free CME) | Endocrine Society LINK COMING 
• Guidelines Pocket Card | Guideline Central LINK COMING 
• Guideline Feature Article | Endocrine News LINK COMING 

Essential Points 

• Pre-existing diabetes (PDM) increases the risk of maternal and perinatal mortality and morbidity.
  • Reduction of maternal hyperglycemia prior to and during pregnancy can reduce these risks.
• Despite strong evidence that preconception care (PCC), which includes achieving strict glycemic goals, reduces the risk of congenital malformations and other adverse pregnancy outcomes, only a minority of individuals receive PCC.

List of Recommendations

Question 1. Should a screening question about pregnancy intention vs. no screening question be used in every healthcare provider appointment for individuals with diabetes mellitus who have the possibility of becoming pregnant?

Recommendation 1

In individuals with diabetes mellitus who have the possibility of becoming pregnant, we suggest asking a screening question about pregnancy intention at every reproductive, diabetes and primary care visit. Screening for pregnancy intent should also be addressed at urgent care/emergency room visits when clinically appropriate. (2 | ⊕OOO)

Technical remarks:

• There are no data supporting a specific timing or frequency of screening.
• A critical component of preconception care (PCC) is optimization of glycemia to reduce adverse pregnancy outcomes, including congenital malformations. The GDP suggests that for screening for pregnancy intent to be effective, three actions are required:
  • Provision of basic counseling about the benefits of PCC
  • Evaluation of contraception needs and/or family planning referral
  • Referral for PCC to achieve goals of therapy.
• This recommendation applies to individuals with all types of PDM, including T1DM and T2DM.

Question 2. Should contraception vs. no contraception be used in individuals with diabetes mellitus who have the possibility of becoming pregnant?

Recommendation 2

In individuals with diabetes mellitus who have the possibility of becoming pregnant, we suggest use of contraception when pregnancy is not desired.  (2 | ⊕⊕OO)

Technical remarks:

• Clinician counseling about contraception should be noncoercive and patient-centered. Shared decision-making should prioritize an individual’s autonomy and be informed by the clinician’s expertise.

Question 3. Should discontinuation of Glucagon-Like Peptide-1 Receptor Agonist (GLP-1RA) before pregnancy vs. GLP-1RA discontinuation between the start of pregnancy and the end of the first trimester be used in individuals with pre-existing type 2 diabetes?

Recommendation 3

In individuals with type 2 diabetes, we suggest discontinuation of Glucagon-Like Peptide-1 Receptor Agonist (GLP-1RA) before conception rather than discontinuation between the start of pregnancy and the end of the first trimester.  (2 | ⊕OOO)

Technical remarks:

• Sudden discontinuation of GLP-1RA may cause hyperglycemia and weight gain, which increases the risk for congenital malformations and spontaneous abortion. Timely transition and titration of alternative antihyperglycemic agents after discontinuing GLP-1 RAs is necessary to minimize hyperglycemia.
• The timing of discontinuation prior to pregnancy is individualized based on the anticipated likelihood of conception after discontinuing contraception, type of GLP-1 RA used, and risks of prolonged time off GLP-1 RAs prior to pregnancy.
• Active management of glycemia is required after GLP1RA discontinuation.

Question 4. Should insulin vs. insulin with the addition of metformin be used in pregnant individuals with pre-existing diabetes type 2?

Recommendation 4

In pregnant individuals with type 2 diabetes mellitus (T2DM) already on insulin, we suggest against routine addition of metformin. (2 | ⊕OOO)

Question 5. Should a carbohydrate restricted (<175 g per day) diet vs. usual diet (>175 g per day) during pregnancy be used in individuals with pre-existing diabetes mellitus (PDM)?

Recommendation 5

In individuals with pre-existing diabetes mellitus (PDM), we suggest either a carbohydrate-restricted diet (<175 g per day) or usual diet (>175 g per day) during pregnancy. (2 | ⊕OOO)

Technical remarks:

• There is no clear evidence on the optimal amount of carbohydrate intake during pregnancy; however, lower and higher extremes are harmful based on indirect evidence.

Question 6. Should a continuous glucose monitor (CGM) vs. no CGM (self-monitoring blood glucose [SMBG] as standard of care) be used in pregnant individuals with type 2 diabetes mellitus (T2DM)?

Recommendation 6

In pregnant individuals with type 2 diabetes mellitus (T2DM), we suggest either continuous glucose monitor (CGM) or self-monitoring of blood glucose (SMBG). (2 | ⊕OOO)

Technical remarks:

• Both CGM and SMBG are considered reasonable alternatives for monitoring glucose during pregnancy, however, in individuals with T2DM, there is limited direct evidence of superiority of CGM use. CGM may offer a potential advantage over SBGM in certain subgroups of preexisting Type 2 diabetes.
• Ideal glycemic ranges, CGM metrics, and % Time in Range (TIR) for individuals for T2DM may be different compared to those which have demonstrated to improve clinical outcomes in T1DM.

Question 7. Should a single continuous glucose monitor (CGM) target < 140 mg/dl (7.8mmol/L) be used vs standard of care pregnancy glucose targets of fasting <95 mg/dl (5.3 mmol/L), 1 hr. post prandial <140 mg/dl (7.8 mmol/L), 2hr post prandial < 120 md/dl (6.7mmol/L) in individuals with pre-existing diabetes mellitus (PDM) using CGM?

Recommendation 7

In individuals with pre-existing diabetes mellitus (PDM) using a continuous glucose monitor (CGM), we suggest against the use of single 24 hour continuous glucose monitor (CGM) target < 140 mg/dl (7.8mmol/L) in place of standard of care pregnancy glucose targets of fasting <95 mg/dl (5.3 mmol/L), 1 hr. post prandial <140 mg/dl (7.8 mmol/L), 2hr post prandial < 120 md/dl (6.7mmol/L) (2 | ⊕OOO)

Technical remarks:

• When CGM is used in individuals with preexisting diabetes, providers and patients should use fasting and postprandial glucose targets (whether measured by CGM or SMBG) as the basis for insulin adjustment and not a single glucose target of 63-140 mg/dl.
• When using CGM in conjunction with HCL, providers should be aware that not all HCL algorithms can meet these targets.
• This recommendation applies to all types of PDM, including T1DM and T2DM.
• There is limited data on the appropriate lower limit of the target for fasting or post prandial glucose in pregnancy.

Question 8. Should a hybrid closed loop pump (pump adjusting automatically based on continuous glucose monitor (CGM)) vs. insulin pump with CGM (without an algorithm) or multiple daily insulin injections with CGM be used in individuals with Type 1 diabetes mellitus (T1DM) who are pregnant?

Recommendation 8

In individuals with Type 1 diabetes mellitus (T1DM) who are pregnant, we suggest the use of a hybrid closed loop pump (pump adjusting automatically based on continuous glucose monitor (CGM)) rather than an insulin pump with CGM (without an algorithm) or multiple daily insulin injections with CGM. (2 | ⊕OOO)

Technical remarks:

• Not all HCL algorithms are appropriate for use in pregnancy. The individual algorithms used in HCL technology vary in their effects on glucometrics and, presumably, on clinical outcomes as well. The decision to use HCL technology—and which specific system to choose—should be made by the patient in collaboration with a clinician experienced in both diabetes management during pregnancy and diabetes technology.

Question 9. Should early delivery based on risk assessment vs. expectant management be used in individuals with pre-existing diabetes mellitus (PDM)?

Recommendation 9

In individuals with pre-existing diabetes mellitus (PDM), we suggest early delivery based on risk assessment rather than expectant management. (2 | ⊕OOO)

Technical remarks:

• There are no validated obstetric risk assessment tools for individuals with pre-existing diabetes.
• Risk-assessment criteria that may be useful to inform ideal delivery timing include the history of diabetes-related complications, measures of glycemia, ultrasound assessment of fetal growth and amniotic fluid volume, and presence of other comorbidities associated with adverse perinatal outcomes.
• Risks may outweigh any benefits of expectant management beyond 38 weeks gestation, even among those with ideal glycemic management.

Question 10. In postpartum individuals with pre-existing diabetes mellitus (PDM) (including those with pregnancy loss or termination), should postpartum endocrine care (comprehensive diabetes management), in addition to usual obstetric care vs. usual obstetric care be used?

Recommendation 10

In individuals with pre-existing diabetes (including those with pregnancy loss or termination), we suggest post-partum endocrine care (diabetes management), in addition to usual obstetric care. (2 | ⊕OOO)

Technical remark:

• In addition to routine obstetric care, immediate postpartum care for individuals with pre-existing diabetes mellitus (PDM) should prioritize glycemic management to support healing, promote lactation, and facilitate the transition to interpregnancy and long-term diabetes management.
• Ideally, postpartum diabetes care should be delivered by a multidisciplinary team that includes physicians specializing in diabetes and/or endocrinology, as well as nurses, dietitians, and certified diabetes care and education specialists. This team should also support ongoing, long-term established follow-up.
• In many cases, postpartum care also serves as preconception care (PCC) for a future pregnancy. Approximately half of all deliveries occur among individuals who already have at least one child, highlighting the opportunity for postpartum care to contribute meaningfully to PCC. There is strong evidence that preconception care improves several pregnancy outcomes in individuals with PDM.