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Conjugated estrogens Pregnancy and Breastfeeding Warnings

Brand names: Cenestin, Enjuvia, Premarin, Premarin Intravenous

Medically reviewed by Drugs.com. Last updated on Feb 29, 2024.

Conjugated estrogens Pregnancy Warnings

AU, US: Use is contraindicated.
UK: Use should be avoided.

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

Comments:
-Discontinue treatment with this drug immediately if pregnancy occurs.
-This drug is not an oral contraceptive, nor will it restore fertility. Woman of child bearing potential should use non-hormonal methods of contraception if taking this drug.

Studies indicated little or no teratogenic or fetotoxic effect to inadvertently fetal exposure to estrogens and progestins during pregnancy.

AU TGA pregnancy category D: Drugs which have caused, are suspected to have caused or may be expected to cause, an increased incidence of human fetal malformations or irreversible damage. These drugs may also have adverse pharmacological effects. Accompanying texts should be consulted for further details.

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

Conjugated estrogens Breastfeeding Warnings

Use should be avoided.

Excreted into human milk: Yes

Comments: Estrogen administration to nursing women has been shown to decrease the quantity and quality of the breast milk.

See references

References for pregnancy information

  1. Heinonen O, Shapiro S; Kaufman DW ed., Slone D. Birth Defects and Drugs in Pregnancy. Littleton, MA: Publishing Sciences Group, Inc. 1977;297.
  2. Product Information. Premarin (conjugated estrogens). Wyeth-Ayerst Laboratories. 2001;PROD.
  3. Cerner Multum, Inc. UK Summary of Product Characteristics.
  4. Product Information. Enjuvia (conjugated estrogens). Barr Pharmaceuticals Inc. 2015.

References for breastfeeding information

  1. Committee on Drugs, 1992 to 1993. The transfer of drugs and other chemicals into human milk. Pediatrics. 1994;93:137-50.
  2. Product Information. Premarin (conjugated estrogens). Wyeth-Ayerst Laboratories. 2001;PROD.
  3. Cerner Multum, Inc. UK Summary of Product Characteristics.
  4. Cerner Multum, Inc. Australian Product Information.
  5. Product Information. Enjuvia (conjugated estrogens). Barr Pharmaceuticals Inc. 2015.

Further information

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