In response to the 2015-2017 Zika virus outbreak, New York City (NYC) identified and monitored infants with birth defects potentially related to congenital Zika virus. Administrative data matches were used to describe the birth characteristics of children born in 2016 meeting screening criteria for birth defects potentially related to congenital Zika virus infection relative to other NYC births and to monitor mortality and Early Intervention Program use through age 2. Among 120,367 children born in NYC in 2016, 463 met screening criteria and 155 met the Centers for Disease Control and Prevention's case definition for birth defects potentially related to congenital Zika virus infection (1.3 per 1000; 95% confidence interval [CI], 1.1-1.5). Post-neonatal deaths occurred among 7.7% of cases (12) and 5.2% of non-cases (8). Odds of referral to the Early intervention Program among children who met screening criteria were lower among children of mothers who were married (OR, 0.60; 95% CI, 0.37-0.97) and among children not classified as cases whose mothers were born in Latin America and the Caribbean (OR, 0.59; 95% CI, 0.37-1.09). Prevalence of birth defects potentially related to congenital Zika virus infection was similar to that seen in other jurisdictions without local transmission. Birth defects attributable to congenital Zika virus infection may also have been present among screened children who did not meet the case definition.