Race and Pregnancy Outcomes in the Twentieth Century: A Long-Term Comparison
研究发现20世纪初约翰霍普金斯医院中，未治疗的梅毒解释了黑人婴儿早产率高于白人婴儿的三分之一，而早产率差异又解释了死产和出生体重差距的相当部分；黑人婴儿因母乳喂养率更高，住院前十天死亡率更低、体重增长更快。
Untreated syphilis explained one-third of the higher prematurity rates of black relative to white babies born at Johns Hopkins in the early twentieth century. Differences in prematurity rates explained 41 percent of the black-white stillbirth gap and one-quarter of the black-white birth weight gap. Black babies had lower mortality and higher weight gain than white babies during the first ten days of life spent in the hospital because of higher black breast-feeding rates. Historically low birth weights may have a long reach: in 1988 maternal birth weight accounted for 5–8 percent of the gap in black-white birth weights.