BackgroundBreastfeeding provides ideal infant nutrition, conferring several health benefits to children and their mothers. Women with inverted nipples, however, face difficulties that force them to prematurely terminate breastfeeding. Whereas available conservative measures for the correction of inverted nipples are of limited success, the use of an inverted syringe may be effective in achieving high rates of infant latching and exclusive breastfeeding. This technique, however, has not been investigated in a clinical trial.Methods/designThis open-label randomized controlled trial aims to investigate whether, in women with inverted nipples, the use of an inverted syringe increases the rate of exclusive breastfeeding at one month compared to standard care. One-hundred healthy women with grade 1 or 2 inverted nipples will be recruited as of 37 weeks of gestation. They will be randomly allocated to standard care (control group) or to an intervention group. The intervention consists of using an inverted syringe to evert the nipple before every breastfeed, starting with the first feed after delivery. The primary outcome measure is the rate of exclusive breastfeeding at 1 month. Secondary outcome measures include exclusive breastfeeding rates at 3 and 6 months, nipple eversion rate, successful latching rate, rates of any breastfeeding at 1, 3, and 6 months, breastfeeding-associated complications, maternal satisfaction with breastfeeding, maternal quality of life, and adverse events. Descriptive and regression analysis will be conducted under the intention to treat basis.DiscussionThe use of the inverted syringe to evert inverted nipples is a simple, inexpensive, and safe technique that can be performed by mothers with inverted nipples. Findings of this trial, if positive, will provide much needed evidence for a safe, affordable, readily available, and simple intervention to treat inverted nipples, and improve breastfeeding practice among affected women.Trial registrationClinicalTrials.gov, NCT03529630. Registered May 8, 2018.