Evolution of anterior fontanel size in normal infants in the first year of life.

To analyze cranial growth and size of anterior fontanel during the first year of life, we undertook a cohort study with a sample of 33 infants assessed at birth and reexamined at 1, 2, 3, 4, 5, 6, 9, and 12 months. Examination included assessment of head circumference, anterior fontanel size, anteroposterior distance, biauricular distance, and cephalic index. All infants were neurologically normal. Mean size of the anterior fontanel at birth was 1.77 cm(2) and, in disagreement with literature data, fontanel size increased up to 2 months of age; fontanel was closed at 1 year for 27.3% of infants. Significant differences in cranial anthropometry were not found in relation to method of delivery (vaginal or cesarean section), gender and gestational age. Our results indicate the need to reevaluate anthropometric examination data and to establish patterns of normality, particularly for miscegenated populations that have not been widely investigated.