Guideline sources The following summarized guidelines for the evaluation and management of diabetes during pregnancy are prepared by our editorial team based on guidelines from the American Diabetes Association (ADA 2023), the Society of Obstetricians and Gynaecologists of Canada (SOGC 2019), the U.S. Preventive Services Task Force (USPSTF 2014), and the Endocrine Society (ES 2013). 1 2 3 4 5 5 6 7 Definition Diabetes during pregnancy is characterized by newly recognized hyperglycemia during pregnancy associated with an increased risk of maternal and neonatal morbidities. 5 Epidemiology Diabetes during pregnancy is caused due to insulin resistance (due to maternal obesity or increased production of diabetogenic placental hormone) in pregnancy and pancreatic -cell dysfunction. 6 Disease course https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 1/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway Diabetes during pregnancy is related to several maternal complications including diabetic ketoacidosis, hypoglycemia, retinopathy, deterioration of nephropathy, gastric neuropathy, miscarriages, pre-eclampsia, polyhydramnios, premature delivery; and perinatal complications including stillbirth, neonatal death, shoulder dystocia, bone fracture, nerve palsy, neonatal hypoglycemia. 7 Prognosis and risk of recurrence There is an increased risk of stillbirth from 36-42 weeks in women with diabetes during pregnancy with a relative risk of 1.34 (95% CI 1.2-1.5) and 17.1 per 10,000 deliveries. 5 Guidelines 1. Screening and diagnosis Indications for screening: As per ADA 2023 guidelines, obtain screening for undiagnosed diabetes in individuals with risk factors planning pregnancy. B Consider testing all individuals of childbearing potential for undiagnosed diabetes. B Show 4 more As per SOGC 2019 guidelines, obtain screening for diabetes in all pregnant individuals between 24-28 weeks of gestation, using a standardized non-fasting 50-g glucose challenge screening test with plasma glucose measured 1 hour later. Do not obtain further testing if the value is < 7.8 mmol/L. Obtain a 2-hour 75-g oral glucose tolerance test with fasting plasma glucose, 1-hour plasma glucose, and 2-hour plasma glucose if the value of the glucose challenge screening is 7.8-11.0. B Show 2 more As per USPSTF 2014 guidelines: Obtain screening for gestational diabetes in asymptomatic pregnant individuals after 24 weeks of gestation. B Insufficient evidence to assess the balance of benefits and harms of screening for gestational diabetes in asymptomatic pregnant individuals before 24 weeks of gestation. I As per ES 2013 guidelines: Obtain screening for diabetes in pregnant individuals at the first prenatal visit, with fasting plasma glucose, HbA1c, or untimed random plasma glucose. B Obtain screening for diabetes in pregnant individuals at 24-28 weeks of gestation, with a 2- hour, 75-g oral glucose tolerance test. B 2. Diagnostic investigations Renal function assessment: consider obtaining renal function assessment (urine albumin-to- creatinine ratio, serum creatinine, and eGFR) in all individuals with diabetes planning conception, before withdrawing contraceptive measures or otherwise trying to conceive. https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 2/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway Show 2 more Thyroid function assessment: measure serum TSH and thyroid peroxidase antibodies, if the thyroid status is unknown, in patients with T1DM planning conception, before withdrawing contraceptive measures or otherwise trying to conceive. B Screening for coronary artery disease: Screen for coronary artery disease in patients with diabetes and several vascular risk factors (particularly the duration of the patient's diabetes and age) planning conception, before withdrawing contraceptive measures or otherwise trying to conceive. B Assess disease severity in patients with diabetes and known coronary artery disease planning conception. Initiate appropriate treatment and provide counseling as to the potential risks of pregnancy to the patient and fetus. A Screening for diabetic retinopathy: As per ADA 2023 guidelines, counsel patients with preexisting T2DM planning pregnancy or who have become pregnant on the risk of development and/or progression of diabetic retinopathy. Obtain dilated eye examinations ideally before pregnancy or in the first trimester, and then monitor patients every trimester and for 1 year postpartum as indicated by the degree of retinopathy and as recommended by the eye care healthcare professional. B As per ES 2013 guidelines, obtain a detailed ocular assessment by a qualified eye care professional in all patients with diabetes planning conception, before withdrawing contraceptive measures or otherwise trying to conceive. A Show 4 more 3. Medical management Setting of care: Manage patients with preexisting diabetes planning a pregnancy ideally beginning in preconception in a multidisciplinary clinic including an endocrinologist, maternal-fetal medicine specialist, registered dietitian nutritionist, and diabetes care and education specialist, when available. B Recognize that telehealth visits for pregnant patients with gestational diabetes mellitus improve outcomes compared with standard in-person care. A Glycemic targets, before pregnancy: consider targeting blood glucose and HbA1c levels as close to normal as possible in patients with diabetes planning to conceive, without causing undue hypoglycemia. C Glycemic targets, during pregnancy: As per ADA 2023 guidelines: Obtain fasting and postprandial blood glucose monitoring in both gestational diabetes mellitus and preexisting diabetes in pregnancy, to achieve optimal glucose levels. Set the following glucose targets: fasting plasma glucose < 95 mg/dL (5.3 mmol/L) and either 1- hour postprandial glucose < 140 mg/dL (7.8 mmol/L) or 2-hour postprandial glucose < 120 mg/dL (6.7 mmol/L). Obtain blood glucose preprandially in some patients with preexisting diabetes. B https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 3/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway Recognize that HbA1c is slightly lower during pregnancy in individuals with or without diabetes due to increased RBC turnover. Set a HbA1c target in pregnancy of < 6% (42 mmol/mol) if this can be achieved without significant hypoglycemia. Consider relaxing the target to < 7% (53 mmol/mol) if necessary to prevent hypoglycemia. B As per ES 2013 guidelines, target blood glucose levels as close to normal as possible in patients with gestational diabetes. B Show 4 more Glycemic targets, after pregnancy: consider targeting blood glucose levels of 72-126 mg/dL (4.0-7.0 mmol/L) during labor and delivery in patients with overt or gestational diabetes. C Initial management, gestational diabetes: As per ADA 2023 guidelines, offer lifestyle behavior changes for the management of gestational diabetes mellitus. Add insulin if needed to achieve glycemic targets. A As per ES 2013 guidelines: Offer lifestyle measures (medical nutrition therapy and daily moderate exercise for 30 minutes) as first-line treatment for gestational diabetes. B Initiate pharmacological therapy if lifestyle therapy is insufficient to maintain normoglycemia in patients with gestational diabetes. A Initial management, preexisting diabetes: Prescribe insulin as the preferred therapy for both T1DM A and T2DM during pregnancy. B Consider prescribing either multiple daily injections or insulin pump technology in pregnancy complicated by T1DM. C Insulin therapy (before pregnancy): prescribe multiple daily doses of insulin or continuous subcutaneous insulin infusion in preference to split-dose, premixed insulin therapy in insulin- treated patients with diabetes planning to conceive because the former are more likely to allow for the achievement and maintenance of target blood glucose levels preconceptionally and, in the event of pregnancy, are more likely to allow for sufficient flexibility or precise adjustment of insulin therapy. B Show 3 more Insulin therapy (during pregnancy): consider prescribing long-acting insulin analog detemir during pregnancy in patients requiring basal insulin, if NPH insulin, in appropriate doses, has previously resulted in problematic hypoglycemia, or would result in a high risk of problematic hypoglycemia. Consider continuing insulin detemir in patients already successfully taking insulin detemir before pregnancy. B Show 3 more Oral antihyperglycemics: As per ADA 2023 guidelines: Do not use metformin and glyburide as first-line therapy, as both cross the placenta to the fetus. Recognize that other oral and non-insulin injectable glucose-lowering medications lack long-term safety data. D Discontinue metformin by the end of the first trimester, when used for the treatment of PCOS and induction of ovulation. A https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 4/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway As per ES 2013 guidelines, consider offering metformin for glycemic control only in patients with gestational diabetes meeting the following criteria: inadequate glycemic control despite medical nutrition therapy refusal of insulin therapy, or inability to use insulin pregnancy in the second or third trimester. C Show 2 more Low-dose aspirin: initiate low-dose aspirin 100-150 mg/day (162 mg/day may also be acceptable) starting at 12-16 weeks of gestation to lower the risk of preeclampsia in patients with T1DM or T2DM. B Management of hypertension: consider targeting a BP of 110-135/85 mmHg in pregnant patients with diabetes and chronic hypertension in the interest of reducing the risk for accelerated maternal hypertension. B Titrate therapy from a BP threshold of 140/90 mmHg for better pregnancy outcomes with no increase in the risk of small-for-gestational-age birth weight. B Lessen therapy for BP < 90/60 mmHg. C Medications to avoid: As per ADA 2023 guidelines, avoid using potentially teratogenic medications, such as ACEIs, ARBs, and statins, in sexually active females of childbearing age not using reliable contraception. D As per ES 2013 guidelines, discontinue ACEIs and ARBs in patients with diabetes planning to conceive. B Show 4 more 4. Nonpharmacologic interventions Dietary modifications: As per ADA 2023 guidelines, encourage a balanced intake of macronutrients including nutrient-dense fruits, vegetables, legumes, whole grains, and healthy fats with omega-3 fatty acids (including nuts, seeds, and fish) in the eating pattern. B As per ES 2013 guidelines, offer medical nutrition therapy in all pregnant patients with overt or gestational diabetes, to help achieve and maintain desired glycemic control while providing essential nutrient requirements. B Show 3 more Weight reduction: Advise weight reduction before pregnancy in patients with diabetes and overweight or obesity. B Consider following the IOM revised guidelines for weight gain during pregnancy in patients with overt or gestational diabetes. 5. Therapeutic procedures Considerations for delivery: offer induction between 38-40 weeks of gestation depending on glycemic control and other comorbidity factors in pregnant patients with gestational or with https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 5/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway pregestational diabetes mellitus. B Show 2 more 6. Patient education General counseling: As per ADA 2023 guidelines, incorporate preconception counseling into routine diabetes care starting at puberty and continuing in all patients with diabetes and reproductive potential. A Show 2 more As per ES 2013 guidelines, provide preconception counseling to all patients with diabetes planning pregnancy. B Show 2 more 7. Preventative measures Preconception care: As per ADA 2023 guidelines, augment standard preconception care with extra focus on nutrition, diabetes education, and screening for diabetes comorbidities and complications, B in addition to focused attention on achieving glycemic targets. A As per ES 2013 guidelines, initiate folic acid supplementation at a dose of 5 mg/day B in patients with diabetes, beginning 3 months before withdrawing contraceptive measures or otherwise trying to conceive, in order to reduce the risk of neural tube defects. B Show 2 more 8. Follow-up and surveillance Monitoring of glycemic control: As per ADA 2023 guidelines, consider obtaining continuous glucose monitoring in addition to pre- and postprandial blood glucose monitoring to achieve HbA1c targets in diabetes and pregnancy. C Show 3 more As per ES 2013 guidelines, obtain self-monitoring of blood glucose in pregnant patients with overt or gestational diabetes. A Show 2 more Monitoring of fetal health: consider obtaining fetal growth assessment starting at 28 weeks of gestation as a baseline and with subsequent serial assessments every 3-4 weeks to assess the effect of maternal glycemic control on fetal growth rate and amniotic fluid volume in patients with pregestational or gestational diabetes mellitus. C Show 2 more Postpartum care, evaluation of glycemic control: As per ADA 2023 guidelines, evaluate and adjust insulin requirements postpartum as insulin resistance decreases dramatically immediately postpartum and the requirements are often roughly half the prepregnancy requirements for the initial few days postpartum. B https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 6/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway Show 4 more As per SOGC 2019 guidelines, obtain a 75-g oral glucose tolerance test between 6 weeks and 6 months postpartum to detect prediabetes and diabetes in patients with gestational diabetes mellitus. B As per ES 2013 guidelines, measure fasting plasma glucose, or advise patients to perform self-monitoring of fasting blood glucose, for 24 to 72 hours after delivery in women who have had gestational diabetes. B Show 2 more Postpartum care (screening for postpartum thyroiditis): consider screening women with T1DM for postpartum thyroiditis with measurement of TSH level at 3 and 6 months postpartum. C Postpartum care, breastfeeding: As per ADA 2023 guidelines, advise breastfeeding to reduce the risk of maternal T2DM. B As per SOGC 2019 guidelines, advise breastfeeding after delivery in all patients with pre- gestational or gestational diabetes mellitus. B As per ES 2013 guidelines: Advise patients with overt or gestational diabetes to breastfeed their infant, whenever possible. A Continue metformin or glyburide therapy during breastfeeding, if necessary, in patients with overt diabetes, if these medications were used successfully during pregnancy. A Postpartum care (contraception): Discuss and implement a contraceptive plan in all patients with diabetes of reproductive potential. A Include psychosocial assessment and support for self-care in postpartum care. B Studies 2023 TOBOGM In women between 4 weeks and 19 weeks 6 days gestation who had a risk factor for hyperglycemia and a diagnosis of gestational diabetes, immediate treatment was superior to no treatment with respect to adverse neonatal outcome. David Simmons et al. N Engl J Med. 2023 Jun 8. References 1. Blumer I, Hadar E, Hadden DR et al. Diabetes and pregnancy: an endocrine society clinical practice guideline. J Clin Endocrinol Metab. 2013 Nov;98 11 4227 49. Open 2. Steven E. Kahn, Cheryl A.M. Anderson, John B. Buse et al. Standards of Care in Diabetes 2023. Diabetes Care. 2023 Jan;46 Supplement_1 S1 S291. Open 3. Howard Berger, Robert Gagnon, Mathew Sermer. Guideline No. 393 Diabetes in Pregnancy. J Obstet Gynaecol Can. 2019 Dec;41 12 1814 1825.e1. Open https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 7/8 6/29/23, 10:10 PM Diabetes during pregnancy Pathway 4. Moyer VA, U.S. Preventive Services Task Force. Screening for gestational diabetes mellitus: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2014 Mar 18;160 6 414 20. Open 5. Melissa G Rosenstein, Yvonne W Cheng, Jonathan M Snowden et al. The risk of stillbirth and infant death stratified by gestational age in women with gestational diabetes. 2012 Apr;206 4 309.e1 7.2012 Apr;206 4 309.e1 7. Open 6. AbdelHameed Mirghani Dirar and John Doupis. Gestational diabetes from A to Z. World J Diabetes. 2017 Dec 15; 8 12 489 511. Open 7. Fathi I Abourawi. Diabetes mellitus and pregnancy. 2006 Jul 4;1 1 28 41.2006 Jul 4;1 1 28 41. Open 8. American Diabetes Association. 14. Management of Diabetes in Pregnancy: Standards of Medical Care in Diabetes 2019. Diabetes Care. 2019 Jan;42 Suppl 1 S165 S172. Open 9. Melissa G. ROSENSTEIN, Yvonne W. CHENG, Jonathan M. SNOWDEN et al. The Risk of Stillbirth and Infant Death Stratified by Gestational Age in Women with Gestational Diabetes. Am J Obstet Gynecol. 2012 Apr; 206 4 309.e1 309.e7. Open 10. Fathi I Abourawi. Diabetes mellitus and pregnancy. Libyan J Med. 2006; 1 1 28 41. Open https://web.pathway.md/diseases/rec8f7VCPdwpi3vjw 8/8