Funding was provided by the Saving Newborn Lives program of Save the Children Federation, Inc. We thank Ellen Boundy, Roya Dastjerdi, Sandhya Kajeepeta, Stacie Constantian, Tobi Skotnes, and Ilana Bergelson for reviewing and abstracting data. Rodrigo Kuromoto and Eduardo Toledo reviewed non-English articles. We acknowledge Kate Lobner for developing and running the search strategy.