Perinatal hypoxia continues to represent a important cause of death, hypoxic ischemic encephalopathy, and cerebral palsy in the world. It is estimated that 23% of neonatal deaths per year occur due to intrapartum complications. The present work will seek to determine if the low cerebroplacental index is a risk factor for adverse perinatal outcome in pregnancies with adequate fetal growth. The study will be analytical, prospective, observational, which will include the pregnant women who come for delivery care at the Víctor Lazarte Echegaray Hospital during the period January - December 2020 and who meet the following selection criteria A cohort study will be carried out in which the relationship between the variables will be evaluated by calculating the relative risk. The 95% confidence interval of the corresponding statistician will be calculated.