Long Term Outcome After Umbilical Artery Acidaemia at Term Birth: Influence of Gender and Duration of Fetal Heart Rate Abnormalities

Objective: To study the outcome after acidaemia at term birth, and the relation to gender and duration of pathological fetal heart rate changes.

Design: Population based study of 154 infants with umbilical artery pH < 7.05 at term birth. Neonatal outcome and the result of developmental screening at age four years were compared with a control group with pH > 7.10. Fetal heart rate traces in infants with acidaemia were reviewed, and the relation between duration of fetal heart rate changes and outcome was analysed.

Results: Of the 154 newborns with acidaemia at birth, 10 had encephalopathy, of which two died and two developed cerebral palsy. Nine of these 10 infants were boys, and eight had pH < 7.00. Male newborns (n = 39) more often had pronounced acidaemia (pH < 7.00) than females (n = 22). Although few infants had severe impairment, infants born with acidaemia significantly more often had speech problems at follow up than controls (19/102 versus 8/98; P = 0.03). In infants with acidaemia, duration of abnormal fetal heart rate changes was significantly associated with neonatal encephalopathy and speech problems at age four years.

Conclusions: Acidaemia at term birth was associated with neonatal encephalopathy and with speech problems at four years of age. Boys had more often pronounced acidaemia and a complicated course. A protracted abnormal fetal heart rate trace was associated with poor outcome.