Prevalence and associated factors of minor neuromotor dysfunctions at age 5 years in prematurely born children

Objectives: To assess the frequency of minor neuromotor dysfunctions ( MNDs) at age 5 years according to gestational age, to test their association with behavioral and learning difficulties, and to find determining neonatal factors. Design: Prospective population- based cohort study of children born in 1997 and followed up from birth to age 5 years. Setting: All maternity wards in 9 regions of France. Participants: A total of 1662 children born before 33 completed weeks of gestation and 2 control groups including 245 children born at 33 to 34 weeks and 332 children born at 39 to 40 weeks. Main Exposure: Birth before 33 weeks. Main Outcome Measure: Short version of the Touwen neurological examination classifying children as healthy, having mild MND ( MND- 1), or having moderate MND ( MND- 2) depending on the number of abnormal neuromotor signs found. Results: Of children born before 33 weeks, 41.4% had MND- 1 and 3.0% had MND- 2. These proportions were 30.8% and 0.5%, respectively, for children born at 33 to 34 weeks and 22.0% and 0.7%, respectively, for children born at 39 to 40 weeks. Minor neuromotor dysfunction was independently associated with learning difficulties at age 5 years ( odds ratio [ OR], 1.6; 95% confidence interval [ CI], 1.1- 2.2). In very preterm children, factors associated with MND- 1 were postnatal corticotherapy ( OR, 1.8; 95% CI, 1.3- 2.6), multiple births ( OR, 0.7; 95% CI, 0.6- 0.9), and, in singletons, breast-feeding ( OR, 0.8; 95% CI, 0.6- 0.99). Being a boy ( OR, 3.1; 95% CI, 1.5- 6.4), having had acute fetal distress ( OR, 2.8; 95% CI, 1.4- 5.5) or severe abnormalities on early cranial ultrasonography ( OR, 2.7; 95% CI, 1.2- 6.2), and having had postnatal corticotherapy ( OR, 2.7; 95% CI, 1.2-6.1) increased the risk of MND- 2. Conclusions: The high rate of MNDs and their association with an increased risk for learning difficulties justify their screening in case of ( even moderate) prematurity.