Effect of antenatal azithromycin for Ureaplasma spp. on neonatal outcome at ≤30 weeks' gestational age.

BACKGROUND: Ureaplasma spp. in the maternal genitourinary tract has come to attention as a cause of preterm labor, spontaneous abortion, chorioamnionitis and adverse outcomes. A few controversies, however, still remain, namely, whether it should be treated aggressively or not. The aim of this study was to evaluate the effect of maternal azithromycin (AZ) treatment for Ureaplasma colonization on neonatal morbidities including bronchopulmonary dysplasia (BPD).

METHODS: A retrospective case-control study of preterm babies delivered at ≤30 weeks of gestational age (GA) from 2012 to 2016 was conducted. Infants whose mothers had confirmed Ureaplasma colonization and treatment with AZ (m-AZ, cases) were matched by GA to control subjects whose mothers did not have Ureaplasma colonization. A subgroup analysis (nUU(+), infants with neonatal respiratory Ureaplasma colonization; nUU(-), infants without colonization) was also performed.

RESULTS: Fifty-five control subjects were matched to 110 m-AZ subjects. The incidence of preterm premature rupture of membranes (P = 0.003) and of moderate-severe BPD (P = 0.010) was significantly higher in the m-AZ group. On subgroup analysis with post-hoc analysis (m-AZ + nUU(+) [I, n = 55] vs m-AZ + nUU(-) [II, n = 55] vs controls [n = 55]), the incidence of moderate-severe BPD was significantly different: 26% (I) vs 22% (II) vs 7% (controls), P = 0.033.

CONCLUSIONS: Maternal Ureaplasma colonization was associated with moderate-severe BPD despite the use of AZ treatment. In addition, if the neonatal respiratory tract was colonized, then moderate-severe BPD developed even with maternal AZ treatment. Hence, selective antenatal and postnatal treatment of Ureaplasma colonization would be needed to control BPD development.