Management of Diabetes and Hypertension in Pregnancy

Introduction to Management

• The American Diabetes Association recommends insulin as the preferred first-line medication for managing both type 1 and type 2 diabetes during pregnancy, with strict glycemic targets of fasting glucose <95 mg/dL and 1-hour postprandial <140 mg/dL, while ACE inhibitors and ARBs must be immediately discontinued due to teratogenicity 1, 2

Preconception Management

• The American College of Obstetricians and Gynecologists suggests target A1C <6.5% before conception to minimize congenital malformations, preeclampsia, and preterm birth 3, 4
• Prescribe effective contraception and maintain its use until glycemic targets are achieved, as recommended by the American Diabetes Association 2, 3

Glycemic Targets During Pregnancy

• The American Diabetes Association recommends fasting plasma glucose <95 mg/dL, 1-hour postprandial glucose <140 mg/dL, and 2-hour postprandial glucose <120 mg/dL 1, 3
• Optimal A1C goal is <6% if achievable without significant hypoglycemia, as suggested by the American Diabetes Association 1, 3

Insulin Management

• The Endocrine Society recommends insulin as the preferred agent because it does not cross the placenta to a measurable extent 5, 3
• Implement physiologic basal-bolus regimens with rapid-acting insulin for meals and long-acting insulin for basal coverage, as recommended by the American Diabetes Association 4

Hypertension Management

• The American College of Cardiology suggests target blood pressure of 110-135/85 mmHg to reduce risk of accelerated maternal hypertension while minimizing impaired fetal growth 6
• Never use ACE inhibitors or ARBs during pregnancy due to fetotoxicity in the second and third trimesters, as recommended by the American Diabetes Association 1, 2

Preeclampsia Prevention

• The American College of Obstetricians and Gynecologists recommends low-dose aspirin 100-150 mg/day starting at 12 to 16 weeks of gestation to lower the risk of preeclampsia 6

Retinopathy Monitoring

• The American Academy of Ophthalmology recommends comprehensive ophthalmologic examination at baseline and as needed throughout pregnancy for women with preexisting diabetic retinopathy 1, 3
• Rapid implementation of tight glycemic control in the setting of retinopathy is associated with worsening of retinopathy, as noted by the American Diabetes Association 5, 3

Medical Nutrition Therapy

• The Academy of Nutrition and Dietetics recommends consistent carbohydrate intake to match insulin dosing and avoid glucose fluctuations 3, 4
• The food plan should provide adequate calories to promote fetal/neonatal and maternal health, achieve glycemic goals, and promote appropriate gestational weight gain, as suggested by the American Diabetes Association 3

Postpartum Management

• The American College of Obstetricians and Gynecologists recommends close monitoring and rapid insulin dose reduction in the immediate postpartum period to prevent hypoglycemia 6, 5, 3
• Women with gestational diabetes should be tested for persistent diabetes or prediabetes at 4-12 weeks postpartum with a 75-g oral glucose tolerance test using nonpregnancy criteria, as recommended by the American Diabetes Association 6, 3

Medication Review in Pregnancy

Immediate Teratogenic Risk

• ACE inhibitors and ARBs cause fetotoxicity in the second and third trimesters and must be stopped at conception or immediately upon pregnancy recognition, according to the American Diabetes Association 7
• Statins are also potentially harmful in pregnancy and should be avoided in women of childbearing age not using reliable contraception, as recommended by the American Diabetes Association 7

Safe Antihypertensive Alternatives

• Target blood pressure should be 110-135/85 mmHg to reduce risk of accelerated maternal hypertension while minimizing impaired fetal growth, as suggested by the American Diabetes Association 7

Why Other Options Are Less Urgent

• The critical window for neural tube closure is 3-4 weeks gestation, making folic acid supplementation less time-sensitive than medication review at 14 weeks gestation, according to the American Heart Association 8
• There is no immediate life-threatening indication for ECG at this booking visit unless the patient has symptoms of cardiac disease, as stated by the American Heart Association 8

Additional Critical Actions After Medication Review

• Start low-dose aspirin 100-150 mg/day immediately (ideally 12-16 weeks gestation) as this patient has multiple high-risk factors: hypertension, diabetes, and likely first antenatal visit, as recommended by the American Diabetes Association 7
• Women with both hypertension and diabetes have significantly increased risk for preeclampsia, according to the American Heart Association 8
• Establish baseline proteinuria assessment with urine albumin-to-creatinine ratio, as suggested by the American Heart Association 8
• Implement frequent self-monitoring of blood glucose with preprandial and postprandial testing, as recommended by the American Diabetes Association 9

Common Pitfall to Avoid

• Do not delay medication review until a later visit - every day of exposure to teratogenic medications increases fetal risk, according to the American Diabetes Association 7
• The booking visit at 14 weeks may already represent delayed presentation, making immediate action even more critical, as stated by the American Heart Association 8

Early Pregnancy Management of Type 2 Diabetes (First Trimester)

Medication Review & Initiation of Insulin

• Discontinue ACE inhibitors, ARBs, and statins immediately because they cause fetal renal anomalies and teratogenicity; initiate insulin as the first‑line agent for glycemic control, since insulin does not cross the placenta and has the best safety profile in pregnancy. 10

Glycemic Targets for the First Trimester

• Aim for fasting plasma glucose < 95 mg/dL (5.3 mmol/L). [11][10]12
• Aim for 1‑hour post‑prandial glucose < 140 mg/dL (7.8 mmol/L). [11][10]12
• Aim for 2‑hour post‑prandial glucose < 120 mg/dL (6.7 mmol/L). [11][10]12
• Target A1C < 6 % (42 mmol/mol) if achievable without significant hypoglycemia; a relaxed target of < 7 % (53 mmol/mol) is acceptable when hypoglycemia risk is high. [11][10][12][13]
• An A1C > 6.5 % during the first 10 weeks of gestation (organogenesis period) is linked to higher rates of anencephaly, microcephaly, congenital heart disease, renal anomalies, and caudal regression. 12

Glucose Monitoring Strategy

• Perform self‑monitoring of fasting and post‑prandial glucose 4–6 times daily (before meals and at bedtime). [10][12]
• Add continuous glucose monitoring (CGM) to assist in reaching A1C targets and to lower hypoglycemia risk. [10][13]
• CGM metrics should supplement, not replace, finger‑stick glucose measurements for achieving pre‑ and post‑prandial goals. [10][13]
• Do not use estimated A1C or glucose‑management‑indicator calculations during pregnancy because they are inaccurate. [10][13]

Folic Acid Supplementation

• Prescribe 400 µg (micrograms) of folic acid daily immediately; this is routine for all pregnant women with diabetes. [11][10]13

First‑Trimester Screening & Assessment

Ophthalmologic Evaluation

• Conduct a dilated comprehensive eye examination as soon as pregnancy is confirmed (or before conception if possible). [10][12]13
• Schedule follow‑up eye exams each trimester and for one year postpartum, with frequency adjusted according to the severity of retinopathy. [10][12]13

Renal Function Assessment

• Measure serum creatinine and urine albumin‑to‑creatinine ratio (instead of only protein‑to‑creatinine ratio) to establish baseline kidney status. [10][14][12][13]

Thyroid Function

• Check thyroid‑stimulating hormone (TSH) level at the first prenatal visit. [11][10][14][13]

Cardiovascular Assessment

• Obtain an electrocardiogram (ECG) for patients aged ≥ 35 years or those with cardiac symptoms or risk factors; pursue further cardiac evaluation if the ECG is abnormal. [11][10]13

Additional Laboratory Screening

• Perform a lipid panel, a comprehensive foot examination, and anemia screening as part of the initial work‑up. [11][10]13

Multidisciplinary Team Coordination

• Arrange care involving an endocrinologist, a maternal‑fetal medicine specialist, a registered dietitian nutritionist, and a diabetes education specialist. [10][12]
• This team‑based approach markedly reduces congenital malformations, preterm delivery, and neonatal intensive‑care admissions. 12

Contraception Planning for Future Pregnancies

• Provide ongoing contraception counseling, emphasizing long‑acting reversible methods until glycemic targets are consistently achieved before attempting another conception. [10][12]

Common Pitfalls & Safety Recommendations

• Do not rely solely on A1C: Pregnancy‑related increased red‑blood‑cell turnover lowers A1C values; therefore, frequent pre‑ and post‑prandial glucose monitoring is essential. [11][10]
• Do not use oral hypoglycemic agents as first‑line therapy: Although metformin and glyburide are used in some settings, insulin remains the preferred first‑line medication with the most robust safety data. 14
• Do not assume normal glucose tolerance after delivery: All women with type 2 diabetes during pregnancy require continued diabetes management and monitoring postpartum. 12