This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus; according to some authorities, use is contraindicated.

AU TGA pregnancy category: B3
US FDA pregnancy category: C

Animal studies have revealed evidence of fetotoxicity at higher oral doses; these studies have failed to reveal evidence of teratogenicity at such doses (11 times the maximum recommended human dose [MRHD] based on mg/m2 or 50 times based on mg/kg in pregnant rats and 4 times the MRHD based on mg/m2 or 10 times based on mg/kg in pregnant rabbits). Decreased fetal body weight and increased fetal mortality were observed at doses 50 (rats) and 10 (rabbits) times the MRHD (based on mg/kg); minor skeletal variations were observed in rats at the same dose. There are no controlled data in human pregnancy; surveillance studies have not reported an increased risk of major birth defects.

Of 549 cases reported by the European Network of Teratology Information Services involving fluoroquinolone exposure (including this drug), congenital malformations were reported in 4.8%; however, this was not higher than the background rate.

Cartilage damage and arthropathy have been reported in immature animals of various species giving rise to concern over possible toxic effects on human fetal bone formation. Because safer alternatives are generally available, some experts consider fluoroquinolones contraindicated during pregnancy, especially during the first trimester.

AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

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.

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LactMed: Use is considered acceptable with monitoring of the infant for possible effects on the gastrointestinal flora (e.g., diarrhea or candidiasis [thrush, diaper rash]); avoiding breastfeeding between 4 to 6 hours after maternal dosing should decrease the infant's exposure to this drug in breast milk.
-According to some authorities, use is contraindicated.
-According to other authorities, 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

Comments:
-The effects in the nursing infant are unknown; potential risk of serious side effects in the nursing infant.

Breast milk drug levels were similar to plasma drug levels in lactating women administered a single 200 mg oral dose.

Cartilage erosion and arthropathy have been observed in immature animals giving rise to concern over toxic effects in the developing joints of nursing infants; however, some studies suggest risk is low. Absorption of the small amounts of fluoroquinolones in milk may be blocked by the calcium in milk; data insufficient to prove or disprove.

Postpartum (time not specified), 10 lactating women received 400 mg orally every 12 hours for 3 doses. At 2 hours after the third dose, milk drug levels were highest and averaged 2.41 mg/L. Milk levels then declined and averaged 1.91 mg/L at 4 hours, 1.25 mg/L at 6 hours, 0.64 mg/L at 9 hours, 0.29 mg/L at 12 hours, and 0.05 mg/L at 24 hours after the dose. Based on peak milk levels in this study, an exclusively breastfed infant would receive up to 0.36 mg/kg daily (estimated) with this maternal dose regimen.

This drug was part of multidrug regimens to treat 2 pregnant women with multidrug-resistant tuberculosis; use was throughout pregnancy and postpartum in 1 patient and postpartum only in the other patient. Their infants were breastfed (extent and duration not specified). At 4.6 and 5.1 years of age, development was normal except for a mild speech delay in 1 child and hyperactivity in the other child.

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