Abstract
Background
Preterm birth with its complications is one of the leading causes of perinatal morbidity and mortality, as well as maternal morbidity, especially in low and middle-income countries. Cervical cerclage is a well-established preventive tool in women at high risk of preterm birth; however, subclinical maternal infection might still cause failure of this method. Thus, adding prophylactic antibiotics, namely macrolides, could prevent preterm birth.
Patients and methods
This was a randomized controlled clinical trial involving two groups of women who underwent vaginal cerclage at Ain Shams University Maternity Hospital. One group received azithromycin 500mg one tablet orally once daily for 3 days every month from 14th week to 34th week gestation, in addition to routine antenatal care; while the other group received usual antenatal care without antibiotic prophylaxis after cerclage. Follow-up was done and we compared the outcomes in each group: gestational age at delivery, birth weight, mode of delivery, maternal complications, and perinatal complications. ClinicalTrials.gov Identifier NCT04278937.
Results
Gestational age at delivery was significantly higher in the azithromycin group (36.8weeks vs 34.1weeks; P = 0.017), with significant prolongation of gestation in the azithromycin group (23.7weeks vs 21.1weeks; P = 0.005). As regards birth weight, it was significantly higher in the azithromycin group (2932.6gm vs 2401.8gm; P = 0.006); however babies with low birth weight (birth weight <2500gm) were non-significantly less frequent in the azithromycin group (3cases vs 7cases; P = 0.165). There was no significant difference between the two groups as regards other outcomes (miscarriage, stillbirth, neonatal intensive care unit admission, antepartum hemorrhage, postpartum pyrexia, need for blood transfusion).
Conclusion
Adding azithromycin as antenatal prophylaxis in women undergoing vaginal cerclage prolongs pregnancy and reduces risk of PTB, with slight increase in birth weight. However, there was no clear effect on incidence of low birth weight, or perinatal morbidity/mortality.