INTRODUCCION: The problem regarding perinatal complications remains a concern in the health sector, both globally and nationally; and its association with inadequate prenatal control is of a significant proportion. The main complications for the newborn are prematurity and low birth weight, while in the mother is Preeclampsia. OBJECTIVE: To determine the association between inadequate prenatal control and perinatal complications at the Sergio E. Bernales National Hospital in the period January to July 2019. METHODS AND ANALYSIS PLAN: A retrospective, observational, analytical, case - control study was conducted. It was performed with a total of 507 patients, made up of newborns treated in the Neonatology service of the Sergio E. Bernales National Hospital in the period from January to June 2019. This sample consisted of 169 cases, including pregnant women and / or newly born who presente...