Effect of sterile vs clean gloves for cervical checks in labor on maternal infection at term: a randomized trial

Abstract

Intrapartum infection usually warrants immediate delivery and impacts 5-12% of term pregnancies, with the most commonly identified pathogenic organism being of the Ureaplasma genus. When performing cervical examinations during labor, providers in the United States commonly use sterile gloves, although there are no data currently to support that this practice reduces rates of infection. Furthermore, in nearly all other settings of Gynecologic care, aside from surgery in an operating room, nonsterile gloves are used. Even though the uterus could be sterile in normal pregnancies, the provider performing the cervical examination must traverse the milieu of vaginal bacteria in order to reach the cervix to perform the exam, introducing vaginal microbiota into the uterus regardless of the type of glove used. This prospective randomized controlled study examines whether the type of glove used (sterile vs clean) impacts the rates of intrapartum infection in patients receiving cervical examinations during labor or induction of labor at term.. This study aimed to evaluate if the glove type (sterile vs clean) used for cervical examinations during labor affects the rates of intrapartum and postpartum infection. This randomized controlled trial assigned eligible and consenting participants to receive cervical examinations during labor with either sterile powder-free polyvinyl chloride examination gloves (current routine practice, control group) or clean powder-free nitrile examination gloves (nonsterile, experimental group). The primary outcome was rates of intrapartum infection (chorioamnionitis). Sample size calculations estimated that 300 participants would be needed with a rate of infection of 10% in the control group and 20% in the experimental group to demonstrate difference between the groups; however, the rates of infection were much lower than expected, at 5.4% and 4.4% in the sterile and clean glove group, respectively. At this point, it was determined futile to continue the study because a sample size of >29,000 participants would be needed, which would not be achievable at a single tertiary care referral center with approximately 3500 deliveries per year. The study was approved by the Eastern Virginia Medical School Institutional Review Board (IRB 21-09-FB-0206), and was registered at ClinicalTrials.gov (identifier NCT05603624; https://clinicaltrials.gov/ct2/show/NCT05603624). A total of 163 participants with singleton pregnancies completed the study; 74 (45%) were randomized to the sterile glove group, and 89 (55%) were randomized to the clean glove group. In the sterile glove group, 4 (5.4%) developed intrapartum infection (chorioamnionitis) and 1 (1.3%) developed postpartum infection (endometritis). In the clean glove group, 4 (4.4%) developed intrapartum infection and 2 (2.2%) developed postpartum infection. There was no significant difference in rates of intrapartum infection (P=1.0) or postpartum infection (P=1.0), or combined rates of infection (including both chorioamnionitis and endometritis; P=.99) between the sterile and the clean glove group. When comparing the participants from both groups who had any intrapartum or postpartum infection (n=11) with those who had no infection (n=152), the former were more likely to be nulliparous (P=.01), have lower gravidity (P<.01) and parity (P<.01), have longer times from first cervical examination to delivery (P=.02), have longer times from rupture of membranes to delivery (P=.0001), undergo cesarean delivery (P=.0002), and experience postpartum hemorrhage (P=.001). Although participants who were in labor for a longer time also likely had more cervical examinations, these data could suggest that duration of labor (P=.02) is more closely associated with infectious morbidity compared with the number of cervical examinations (P=.15). Using clean gloves for cervical examinations during labor is unlikely to increase risk of infection, and could reduce cost by up to 92.4% at our institution, saving over $25,000 annually.