In rat reproductive studies, mild fetotoxic effects were observed at dose levels from 5 to 50 mg/kg. This perinatal effect is believed to be directly related to the hypoglycemic action of the drug. No teratogenic effects were found in rats and rabbits. Data from published data and postmarketing experience have not identified drug associated risks for major birth defects, miscarriage, or adverse maternal outcomes, however, neonates born to mothers receiving a sulfonylurea at the time of delivery have experienced prolonged severe hypoglycemia, especially with those having prolonged half-lives. Poorly controlled diabetes during pregnancy is associated with risks to the mother and fetus. In women with pre-gestational diabetes and a HbA1c greater than 7, an estimated background risk of major birth defects of 6% to 10% has been shown, and for women with a HbA1c greater than 10, this has been shown to be as high as 20% to 25%. Sulfonylureas may not be suitable for the treatment of diabetes during pregnancy as significant metabolic changes occurring during this time make control of blood sugar difficult. There are no adequate and well-controlled studies in pregnant women.

AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

Use only if clearly needed and the benefit outweighs the risk

AU TGA pregnancy category: C
US FDA pregnancy category: C (immediate-release); Not assigned (extended-release)

Risk Summary: Drug associated risks for major birth defects, miscarriage, or adverse maternal outcomes have not been identified with use of this drug during pregnancy, however, this drug crosses the placenta and has been associated with neonatal adverse reactions such as hypoglycemia; poorly controlled diabetes in pregnancy is associated with risks to the mother and fetus.

Comments:
-Insulin is recommended during pregnancy to maintain blood glucose levels as normal as possible.
-If this drug is used during pregnancy, it should be discontinued at least 2 to 4 weeks before the expected delivery date.

See references

Benefit should outweigh risk

Excreted into human milk: Yes

Comments:
-If diet alone is inadequate for controlling blood glucose, insulin should be considered as alternative therapy.
-Breastfed infants should be monitored closely for signs of hypoglycemia; if there is a concern, blood glucose monitoring is advisable.

Limited data suggests low levels of this drug are present in breast milk. Based on milk concentrations in 2 women, it is estimated that the maximum dose a fully breastfed infant would receive is less than 27% of the weight-adjusted maternal dose. Due to the potential for hypoglycemia in the nursing infant, the manufacturer suggests women who are not able to manage their blood sugar on diet alone consider insulin therapy while breastfeeding.

See references