Early motor development of breech- and cephalic-presenting infants

This study was conducted to determine whether breech-presenting infants have a different pattern of early neuromotor development than cephalic-presenting infants--regardless of mode of delivery-thus explaining both the failure to assume cephalic version at the end of gestation and the higher rates of childhood motor impairments associated with breech presentation.

Ninety morphologically normal, term, breech-presenting singletons with birthweights greater than 2,500 g were paired with a similar cephalic-presenting infant, matched for gender and mode of delivery (n = 180; 100 delivered abdominally and 80 delivered vaginally). Data on neurological status (Neurological Assessment of the Preterm and Full-term Newborn Infant) and motor performance (Alberta Infant Motor Scale, Peabody Developmental Motor Scales, and age of walking) were collected prospectively over the first 18 months of life. This study was designed with a power of .80 to detect a "medium" effect size for motor development using the Alberta Infant Motor Scale. The data were analyzed using analysis of variance techniques.

Breech-presenting infants had minor transient differences compared with cephalic-presenting infants. First, they had more open popliteal angles at birth (P < .001). Second, they had significantly lower motor scores at 6 weeks than the normative sample (P < .001). At 18 months, three infants were diagnosed with neurological problems, all of whom were delivered electively in the cesarean-breech group.

As a group, breech-presenting infants do not have a persistent, inherently different pattern of motor development than cephalic-presenting infants. Mode of delivery did not explain the excess neuromotor impairment detected in the subgroup of breech infants.