Few studies have examined the associations between screen time and child outcomes to decipher their directionality. This study sought to determine the directionality of the association between poor performance on a developmental screening questionnaire and increased screen time. The study subjects were 2441 women (mean age = 30.60) and their infants (who were followed at 24, 36, and 60 months). At each time point, the mothers completed screening questionnaires to identify developmental delays in their children’s communication, gross motor, fine motor, problem solving, and personal-social domains. Mothers also reported on their children’s screen time (hours per week). Screen time at 24 months and 36 months predicted poor achievement of developmental milestone at 36 and 54 months, respectively. The obverse association was not found. These data indicate that high levels of early childhood screen time place children at risk of poor developmental outcomes later in childhood. Pediatricians and other health care professionals should develop personalized media plans with families with young children, in accordance with young recommended guidelines.