He oversaw early clinical trials of the first oral contraceptive pill in Puerto Rican women and later became a professor of human reproduction at the University of Pennsylvania.
He soon moved to Boston to work at Harvard Medical School with Rock, commuting frequently to Puerto Rico to manage the contraceptive pill trials.
García was hired by Pincus as a senior scientist at the Worcester Foundation for Biomedical Research in 1960 and became chief of the infertility clinic at Massachusetts General Hospital in 1962.
In Pennsylvania, he pioneered what he called "conservational surgery" for fallopian tube defects, which in the pre-IVF era was the only fertility-preserving treatment for women with tubal disease.
[2] After a sabbatical in Germany with Kurt Semm, García established one of the first programs for minimally invasive laparoscopic surgery in the United States.