Threatened preterm labor is a risk factor for impaired cognitive development in early childhood.

The aim of this study was to evaluate threatened preterm labor during pregnancy as a risk factor of neurodevelopmental deficits of children at 2 years of age. Two-year-old children who were born late preterm (n=22) or at term after threatened preterm labor (n=23) were compared with at-term control children (n=42). Neurodevelopment was evaluated at a corrected age of 24-29 months with the use of the Merrill-Palmer-Revised Scales of Development. Children who were born at term after threatened preterm labor had lower scores than control children on global cognitive index (95.4 vs 104.2; P=.011), cognition (95.1 vs 103.1; P=.021), fine motor (95.2 vs 103.4; P=.003), gross motor (84.7 vs 99.8; P=.001), memory (92.9 vs 100.4; P=.015), receptive language (93.9 vs 102.9; P=.03), speed of processing (105.7 vs 113.3; P=.011), and visual motor coordination (98.8 vs 106.7; P=.003) subtests. Children born at term after threatened preterm labor had an increased risk of mild neurodevelopmental delay compared with control children (odds ratio for global cognitive index, 2.06; 95% confidence interval, 1.09-3.88; P=.033). There were no significant differences in any cognitive domain between children who were born late preterm and children who were born at term after threatened preterm labor. CONCLUSIONS: Threatened preterm labor is a risk factor for impaired cognitive development at 2 years of age, even if birth occurred at term