Repeated administration to pregnant rats and rabbits during the period of organogenesis resulted in embryofetal loss in all pregnant rats and one-half of pregnant rabbits. There were no malformations of the surviving fetuses. In an analysis of human pregnancy exposures from 1999 to 2015 in which women had taken doses of 30 mg or greater during conception or pregnancy, no maternal or fetal deaths were reported. The analysis reviewed data for 784 pregnancies of which 462 had outcome data; 302 elective abortions (2 for fetal anomalies including 1 with trisomy 21); 63 spontaneous abortions, 13 ectopic pregnancies, and 84 births. Of the 84 births, 5 infants had congenital anomalies (4 major malformations [2/4 with genetic syndromes]). From this analysis, it appears that a single-dose of this drug was not associated with a pattern of increased risk of adverse outcomes. There are no controlled data in human pregnancy.

A pregnancy registry in the UK is suggested for any pregnancy in a woman who has taken this drug for emergency contraception : www.hra-pregnancy-registry.com

Most women taking a therapeutic dose of this drug have anovulation, however, the level of fertility while taking multiple doses has not been studied. Ovulation and menstruation may be expected to resume 1 month after the end of treatment.

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.

Contraindicated

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

Risk Summary: Postmarketing studies have not shown a signal of concern regarding pregnancy complications with single-dose emergency contraceptive use during early pregnancy.

Comments:
-This drug is contraindicated for use during an existing or suspected pregnancy.
-Because concomitant administration of this drug with progestin-containing contraceptives may decrease the effectiveness of both drugs, progestin-containing oral contraceptives should not be started or resumed for at least 5 days after use of this drug; a reliable barrier method of contraception should be used with subsequent acts of intercourse that occur in that same menstrual cycle.

See references

This drug and its active metabolite are present in breastmilk in small amounts. For women taking a single 30-mg dose, a fully breastfed infant would be expected to receive a weight-adjusted dose of approximately 0.8% on day 1 and approximately 1% of the maternal dose over following 5-days. There is no information on the effects of this drug on the breastfed child or the effects on milk production. It has been suggested that breastfeeding be avoided for 1 week and mothers should express and discard their breast milk in order to stimulate lactation.

Use is not recommended

Excreted into human milk: Yes

Comments:
-When used as a single-dose emergency postcoital contraceptive (30-mg dose), some authorities recommend withholding breastfeeding for 24 hours, other authorities recommend waiting 1-week after dosing.
-When taking this drug daily (5-mg dose) to treat the symptoms of uterine fibroids, breastfeeding is not recommended as a risk to the newborn/infant cannot be excluded.

See references