Mary Delgado’s first pregnancy went according to plan, but when she tried to get pregnant again seven years later, nothing happened. After 10 months, Delgado, now 34, and her partner, Joaquin Rodriguez, went to see an OB-GYN. Tests showed she had endometriosis, which was interfering with conception. Delgado’s only option, the doctor said, was in vitro fertilization. “When she told me that, she broke me inside,” Delgado said, “because I knew it was so expensive.” Delgado, who lives in New York City, is enrolled in Medicaid, the federal-state health program for low-income and disabled people. Th…