Efficacy and Safety of Meropenem in Pregnant Women with Upper Urinary Tract Infections: A Retrospective Cohort Study in Romania

Introduction: Upper urinary tract infections (UUTIs) are among the most common serious infections during pregnancy and may be associated with maternal and fetal complications. The increasing prevalence of multidrug-resistant pathogens has led to the use of broader-spectrum antibiotics, including meropenem. However, data regarding the safety and efficacy of meropenem in pregnant women remain limited. The aim of this study was to evaluate the indications, efficacy, and safety of meropenem treatment in pregnant women with UUTIs and its impact on maternal and fetal outcomes. Methods: We conducted a retrospective study over a 12-year period including pregnant women hospitalized with UUTIs who received meropenem. The control group consisted of pregnant women with UUTIs who were treated with ceftriaxone during the same period. Results: Pregnant women treated with meropenem were more frequently diagnosed in the third trimester of pregnancy (p = 0.01) and were more often multiparous (p = 0.006). Sepsis and septic shock occurred significantly more frequently in the study group (p < 0.01), and multivariate analysis identified them as the main indications for meropenem administration (OR 10.54, 95% CI 3.30–33.70 for sepsis; OR 3.28, 95% CI 1.01–10.62 for septic shock). Patients in the study group had a higher rate of transfer to the obstetrics clinic (p = 0.032), a longer duration of antibiotic therapy (p = 0.031), and a longer hospital stay (p < 0.01). No maternal deaths were reported in either group. The rate of adverse pregnancy outcomes was similar between the two groups, except for the Apgar score, which was lower in the meropenem group (p = 0.007). Escherichia coli and Klebsiella pneumoniae were the most frequently isolated pathogens in both groups. Conclusions: Meropenem therapy in pregnant women with UUTIs was mainly indicated in cases of sepsis and septic shock and was associated with favorable maternal clinical evolution, even in patients with severe infections. The rate of adverse pregnancy outcomes was similar between the two groups, although a lower Apgar score was observed in the meropenem group; the severity of illness in the meropenem group should be considered when interpreting the lower Apgar scores. Further prospective multicenter studies are needed to better evaluate the safety and clinical effectiveness of meropenem during pregnancy.