Key Points
- Maternal hyperglycemia in the first few weeks of pregnancy increases the risk of fetal malformations, spontaneous abortions, and perinatal mortality.
- There is a continuous graded relationship between higher maternal glucose and increasing frequency of caesarian section, preeclampsia, fetal macrosomia, and fetal morbidity.
- Before conception, glycemic control should be as close to normal as possible when this can be safely achieved.
- At the first prenatal visit (before 13 weeks gestation or as soon as possible thereafter) all women not known to already have diabetes should be tested for diabetes.
- At 24-28 weeks gestation, all pregnant women not known to already have gestational or overt diabetes should be tested for gestational diabetes.
Preconception Care
Preconception Care of Women with Diabetes
- 1.1. The Endocrine Society (ES) recommends preconception counseling be provided to all women with diabetes who are considering pregnancy. (1|⊕⊕◯◯)
- Preconception counseling can optimally be provided by a multidisciplinary team that includes the diabetes specialist, diabetes educator, dietitian, obstetrician, and other healthcare providers, as indicated.
- If possible, and with the patient’s consent, the woman’s partner can be included as part of a supportive and mentoring therapeutic relationship.
- Preconception counseling should include a discussion regarding:
- the need for pregnancy to be planned and to occur only when the woman has sufficient glycemic control, has had appropriate assessment and management of comorbidities including hypertension and retinopathy, has discontinued potentially unsafe (during pregnancy) medications, and has been taking appropriate folate supplementation beforehand
- the importance of smoking cessation
- the major time commitment and effort required by the patient in both self-management and engagement with the healthcare team, both before conception and during pregnancy
- the importance of notifying the healthcare team without delay in the event of conception.
Preconception Glycemic Control
- 1.2. ES suggests women with diabetes seeking to conceive strive to achieve blood glucose and HbA1c levels as close to normal as possible when they can be safely achieved without undue hypoglycemia. (2|⊕⊕◯◯) (see Recommendations 3.2a-d and Table 3.)
Insulin Therapy
- 1.3a. ES recommends insulin-treated women with diabetes seeking to conceive be treated with multiple daily doses of insulin or continuous SC insulin infusion in preference to split-dose, premixed insulin therapy, because the former are more likely to allow for the achievement and maintenance of target blood glucose levels before conception and, in the event of pregnancy, are more likely to allow for sufficient flexibility or precise adjustment of insulin therapy. (1|⊕⊕◯◯)
- 1.3b. ES suggests a change to a woman’s insulin regimen, particularly when she starts continuous SC insulin infusion, be undertaken well in advance of withdrawing contraceptive measures or otherwise trying to conceive to allow the patient to acquire expertise in, and the optimization of, the chosen insulin regimen. (U)
- 1.3c. ES suggests insulin-treated women with diabetes seeking to conceive be treated with rapid-acting insulin analog therapy (with insulin aspart or insulin lispro) in preference to regular (soluble) insulin. (2|⊕⊕◯◯)
- 1.3d. ES suggests women with diabetes successfully using the long-acting insulin analogs insulin detemir or insulin glargine before conception may continue with this therapy during pregnancy. (2|⊕⊕◯◯)
Folic Acid Supplementation
- 1.4. ES recommends, beginning 3 months before withdrawing contraceptive measures or otherwise trying to conceive, a woman with diabetes take a daily folic acid supplement to reduce the risk of neural tube defects. (1|⊕⊕◯◯) ES suggests a daily dose of 5 mg based on this dose’s theoretical benefits. (2|⊕⊕◯◯)
Ocular Care (preconception, during pregnancy, and postpartum)
- 1.5a. ES recommends all women with diabetes who are seeking pregnancy have a detailed ocular assessment by a suitably trained and qualified eye care professional in advance of withdrawing contraceptive measures or otherwise trying to conceive (1|⊕⊕⊕⊕), and if retinopathy is documented, the patient should be apprised of the specific risks to her of this worsening during pregnancy. If the degree of retinopathy warrants therapy, we recommend deferring conception until the retinopathy has been treated and found to have stabilized. (1|⊕⊕⊕⊕)
- 1.5b. ES recommends women with established retinopathy be seen by their eye specialist every trimester, then within 3 months of delivering, and then as needed. (1|⊕◯◯◯)
- 1.5c. ES suggests pregnant women with diabetes not known to have retinopathy have ocular assessment performed soon after conception and then periodically as indicated during pregnancy. (2|⊕⊕◯◯)
Renal Function (preconception and during pregnancy)
- 1.6a. ES suggests all women with diabetes considering pregnancy have their renal function assessed (by measuring their urine albumin-to-creatinine ratio, serum creatinine, and estimated GFR) in advance of withdrawing contraceptive measures or otherwise trying to conceive. (U) ES suggests that a woman with diabetes who has a significantly reduced GFR be assessed by a nephrologist before pregnancy, both for baseline renal assessment and to review the woman’s specific risk of worsening renal function in the event of pregnancy. (U)
- 1.6b. ES suggests all women with diabetes and preconception renal dysfunction have their renal function monitored regularly during pregnancy. (U)
Management of Hypertension
- 1.7a. ES recommends satisfactory BP control (<130/80 mm Hg) be achieved and maintained before withdrawing contraception or otherwise trying to conceive. (1|⊕⊕◯◯)
- 1.7b. ES recommends a woman with diabetes who is seeking conception while taking an ACE inhibitor or ARB in almost all cases should discontinue the medication before withdrawing contraceptive measures or otherwise trying to conceive. (1|⊕⊕◯◯)
- 1.7c. ES suggests in the exceptional case where the degree of renal dysfunction is severe and there is uncertainty about when conception will occur, physicians and patients be engaged in shared decision-making about whether to continue ACE inhibitors or ARBs. These patients should be informed about the possible loss of renal protective properties if the medication is discontinued and the risk of teratogenesis if it is continued. (U)
- 1.7d. ES recommends when ACE inhibitors or ARBs have been continued up to the time of conception that the medication should be withdrawn immediately upon the confirmation of pregnancy. (1|⊕⊕◯◯)
Elevated Vascular Risk
- 1.8a. ES recommends that if a woman with diabetes has sufficient numbers of vascular risk factors (particularly the duration of the woman’s diabetes and her age), screening studies for CAD be undertaken in advance of withdrawing contraceptive measures or otherwise trying to conceive. (1|⊕◯◯◯)
- 1.8b. ES recommends if a woman with diabetes is seeking pregnancy and has CAD, its severity should be ascertained, treatment instituted, and counseling provided as to the potential risks of pregnancy to the woman and fetus before the woman withdraws contraception or otherwise tries to conceive. (1|⊕⊕⊕⊕)
Management of Dyslipidemia
- 1.9a. ES recommends against the use of statins in women with diabetes who are attempting to conceive. (1|⊕⊕◯◯)
- 1.9b. in view of their unproven safety during pregnancy, ES suggests against the routine use of fibrates and/or niacin for women with diabetes and hypertriglyceridemia attempting to conceive. (2|⊕⊕◯◯)
- 1.9c. ES suggests bile acid-binding resins may be used in women with diabetes to treat hypercholesterolemia. However, this is seldom warranted. (2|⊕⊕◯◯)
Thyroid Function
- 1.10. For women with type 1 diabetes seeking conception, ES recommends measurement of serum TSH and, if their thyroid peroxidase status is unknown, measurement of thyroid peroxidase antibodies before withdrawing contraceptive measures or otherwise trying to conceive. (1|⊕◯◯◯)
Overweight and Obesity
- 1.11. ES recommends weight reduction before pregnancy for overweight and obese women with diabetes. (1|⊕⊕⊕◯)