John Cutler is the researcher in question. He was a public health medical officer. His study was conducted for 2 years in the mid 40s. He exposed prostitutes that already had syphilis or gonorrhea to the Guatemalan prisoners.

Pregnant mothers infected with the disease can pass it to the baby developing in their womb. This is called congenital syphilis.
Syphilis is widespread in the United States. It mainly affects sexually active adults ages 20 to 29.