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Metformin / pioglitazone Pregnancy and Breastfeeding Warnings

Medically reviewed by Last updated on Mar 30, 2023.

Metformin / pioglitazone is also known as: ActoPlus Met, ActoPlus Met XR

Metformin / pioglitazone Pregnancy Warnings

Benefit should outweigh risk

US FDA pregnancy category: Not Assigned

Risk summary: Abnormal blood glucose concentrations during pregnancy are associated with a higher incidence of congenital anomalies, increased neonatal morbidity, and mortality. Most experts recommend insulin use during pregnancy to maintain blood glucose concentrations as close to normal as possible.

Comment: Premenopausal anovulatory women may be at risk for pregnancy with use of pioglitazone; these women should be informed of pregnancy risk.

Published studies with metformin use during pregnancy have not reported a risk of major birth defects or miscarriage risk. Animal studies using pioglitazone at 10 to 40 times the maximum recommended human dose have shown increased rates of postimplantation loss, delayed development, reduced fetal weights, and delayed parturition. There are no adequate and well-controlled studies in pregnant women.

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.

See references

Metformin / pioglitazone Breastfeeding Warnings

UK: Use is contraindicated.
US: A decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.

Excreted into human milk: Yes, in small amounts (metformin); Unknown (pioglitazone)
Excreted into animal milk: Yes (metformin); Yes (pioglitazone)

Comments: The effects in the nursing infant are unknown.

See references

References for pregnancy information

  1. "Product Information. Actoplus Met (metformin-pioglitazone)." Takeda Pharmaceuticals America (2005):
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  3. "Product Information. Actoplus Met XR (metformin-pioglitazone)." Takeda Pharmaceuticals America (2016):

References for breastfeeding information

  1. "Product Information. Glucophage (metformin)." Bristol-Myers Squibb (2001):
  2. "Product Information. Actoplus Met (metformin-pioglitazone)." Takeda Pharmaceuticals America (2005):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.