No Association Between Umbilical Cord pH and Special Educational Needs Among Children With Normal 5-Minute Apgar Scores

AIM: Most infants with a low cord pH have reassuring 5-min Apgar scores of 7-10, but their long-term outcomes have been poorly studied. We examined whether cord pH predicted later special educational needs (SEN).

METHOD: This nationwide register-based study was conducted in Denmark, which provides universal cord pH screening. It comprised singletons born after 35 weeks of gestation from 2006 to 2013, with 5-min Apgar scores of 7-10 and cord pH values of < 7.0, 7.0-7.09, and ≥ 7.1. Information on SEN was obtained from national registers until June 3, 2020, when the children were 6.5-14.5 years of age. Associations between cord pH and SEN were analysed using multivariable Cox regression, and eight-year cumulative incidence estimates were calculated.

RESULTS: We found that 1121 of the 318 486 (0.4%) infants had cord pH values of < 7.0 and 8582 (2.7%) had 7.0-7.09. The adjusted hazard ratio for SEN was 0.95 (p = 0.73) for a cord pH of < 7.0 and 0.98 (p = 0.72) for 7.0-7.09, compared with a pH of ≥ 7.1. The eight-year cumulative incidence of SEN was similar in the groups.

CONCLUSIONS: Cord pH was not associated with later SEN in children born after 35 weeks of gestation who had reassuring 5-min Apgar scores.