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Megestrol Pregnancy and Breastfeeding Warnings

Brand names: Megace, Megace ES

Medically reviewed by Drugs.com. Last updated on Aug 10, 2023.

Megestrol Pregnancy Warnings

Use is contraindicated.

AU TGA pregnancy category: D
US FDA pregnancy category: Not assigned.

Risk Summary: Based on animal data, this drug can harm a developing fetus. There are no available human data to assess for any drug-associated risks of miscarriage, birth defects, or adverse maternal or fetal outcomes.

Comments:
-Adequate methods of contraception should be encouraged.
-Verify negative pregnancy status in females of reproductive potential prior to initiating therapy.
-If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential harm to the fetus.

Animal studies showed a reduction in fetal weight and number of live births, and feminization of male fetuses at doses below maximum recommended clinical dosing based on body surface area. There are no controlled data in human pregnancy.

US FDA pregnancy category D: There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or 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.

See references

Megestrol Breastfeeding Warnings

The Centers for Disease Control and Prevention recommend that HIV-1 infected mothers not breastfeed their infants to avoid risking postnatal transmission of HIV-1.

Use is not recommended.

Excreted into human milk: Yes

Comments:
-The effects in the nursing infant are unknown.
-Animal studies have shown that high doses of progestogens can cause masculinization of the female fetus.
-Because of the potential for HIV transmission and adverse effects on a breastfed infant, breastfeeding is not recommended while taking this drug.

See references

References for pregnancy information

  1. Cerner Multum, Inc. UK Summary of Product Characteristics.
  2. Cerner Multum, Inc. Australian Product Information.
  3. Product Information. Megestrol Acetate (megestrol). Par Pharmaceutical Inc. 2019.

References for breastfeeding information

  1. Cerner Multum, Inc. UK Summary of Product Characteristics.
  2. Cerner Multum, Inc. Australian Product Information.
  3. Product Information. Megestrol Acetate (megestrol). Par Pharmaceutical Inc. 2019.

Further information

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