Gliclazide Should Not Be Used During Pregnancy
Gliclazide is not recommended for use during pregnancy and should be replaced with insulin, which is the preferred and safest medication for managing diabetes in pregnant women. 1
Why Gliclazide Is Not Appropriate
Lack of Safety Data and Guideline Recommendations
All major diabetes guidelines explicitly state that insulin is the preferred agent for managing both type 1 and type 2 diabetes during pregnancy. 1
Sulfonylureas (the drug class that includes gliclazide) are known to cross the placenta, with studies showing umbilical cord concentrations reaching approximately 70% of maternal levels. 1
The American Diabetes Association specifically states that metformin and glyburide should not be used as first-line agents, and all oral agents lack long-term safety data. 1
While gliclazide specifically has minimal published data, the available evidence on sulfonylureas as a class shows associations with increased neonatal hypoglycemia and macrosomia compared to insulin. 1
Evidence Specific to Gliclazide
Only one small comparative study exists (n=108 exposed pregnancies) comparing gliclazide to metformin, which found no significant differences in maternal hospitalizations or neonatal outcomes, but this study is severely limited by sample size and does not compare gliclazide to the gold standard (insulin). 2
The few case reports of gliclazide exposure during pregnancy describe normal outcomes but explicitly state these do not indicate safety and should not be interpreted as acceptable indications for use. 3, 4
There are no long-term follow-up studies on children exposed to gliclazide in utero, which is a critical gap given emerging concerns about metabolic programming. 1
What to Do Instead
Immediate Action Required
Switch to insulin immediately as it does not cross the placenta to a measurable extent and has decades of safety data in pregnancy. 1
Start with basal insulin (NPH, detemir, or glargine) at 0.1-0.2 units/kg/day, with dose adjustments based on blood glucose monitoring. 1
Multiple daily injections or continuous subcutaneous insulin infusion are both acceptable delivery methods, with neither shown to be superior during pregnancy. 1
Glycemic Targets During Pregnancy
- Fasting glucose: <95 mg/dL 1
- One-hour postprandial: <140 mg/dL 1
- Two-hour postprandial: <120 mg/dL 1
- HbA1c: <6% if achievable without significant hypoglycemia 1
Critical Pitfalls to Avoid
Do not continue oral agents during pregnancy based on convenience or patient preference alone—the lack of long-term safety data on offspring is a serious concern that outweighs short-term convenience. 1
Do not assume that one or two case reports of normal outcomes indicate safety—these explicitly do not establish safety and contribute only minimally to knowledge about human exposure. 3, 4
Do not delay switching to insulin—early and optimal glycemic control is essential for reducing risks of congenital anomalies, macrosomia, and other adverse pregnancy outcomes. 1
If the patient was using gliclazide for polycystic ovary syndrome to induce ovulation, it should have been discontinued by the end of the first trimester at the latest. 1, 5
Special Considerations
Women with diabetes in pregnancy require low-dose aspirin (81 mg/day) starting by the end of the first trimester to reduce preeclampsia risk. 1
Insulin requirements will change dramatically throughout pregnancy, with increased resistance in the second and third trimesters, followed by a rapid drop immediately after delivery. 1
Education on hypoglycemia prevention, recognition, and treatment is essential for both the patient and family members, as pregnancy alters counterregulatory responses. 1