Study procedure: randomization and vaginal seeding.
’s mouth
STERILE, OBESE, VAGINA, BLIND
On the day of the scheduled C-section, a team member blind to treatments inserted a gauze moistened with sterile saline into the mother’s vagina. The gauze was incubated in the vagina for approximately 1 h and then removed and placed into a lidded sterile container prior to the mother receiving perioperative antibiotics (with the exception of 2 mothers who were penicillin allergic and received clindamycin and gentamicin when the gauze was still in the vagina due to the longer antibiotic infusion time) and kept at room temperature. Shortly after the insertion of the vaginal gauze, a control gauze was also made by identical preparation of the gauze (i.e., folding of the gauze and moistening with sterile saline following the same protocol as the vaginal gauze) but without insertion into the mother’s vagina. The control gauze was also placed in a separate lidded sterile container and kept at room temperature. A team member not blind to the treatments then randomized the mother to either the vaginal seeding arm or the control arm. Randomization occurred in a 1:1 ratio and was also stratified to the following 3 prepregnancy BMI strata: normal weight, overweight, and obese.In the operating room, after C-section delivery of the infant and prior to the infant having skin-skin contact with its mother, the infant was wiped down with the vaginal seeding gauze or the control gauze by a team member who was blind to the treatments. The gauze was wiped first over the infant’s mouth, followed by the face and the rest of the body in a standardized manner as described previously, typically just after the 1-min Apgar score was taken (