Maternal fever in term labour in relation to fetal tachycardia, cord artery acidaemia and neonatal infection

OBJECTIVE: To determine 1. whether maternal fever during term labour is associated with acidaemia at birth and neonatal infection and 2. whether fetal tachycardia precedes maternal fever and is associated with neonatal infection. DESIGN: Retrospective matched-pair case-control study. SUBJECTS: Two hundred and forty-eight newborn infants whose mothers developed fever during term labour (cases) and 248 control infants. The women were matched for parity and duration of labour. MAIN OUTCOME MEASURES: Cord artery acid-base status, Apgar scores, neonatal infections, and fetal heart rate before maternal fever. RESULTS: Mean pH, as well as the rate of cord artery acidaemia at birth (pH < 7.10) was equal in cases and controls (in both groups 7.24% and 6%, respectively). Signs of septicaemia and/or pneumonia were identified in 17 case newborns (7%) and in one control (0.4%; OR 17.0, P < 0.001). Of 212 pairs with complete heart rate data, fetal tachycardia preceded maternal fever in 39 cases (18%) and in 16 controls (8%) (OR 2.6, P = 0.003). Tachycardia before maternal fever was not associated with increased neonatal infectious morbidity. CONCLUSIONS: Maternal fever during term labour was associated with perinatal infection, but not with acidaemia at birth. Elevated fetal heart rate preceded maternal fever in a minority of cases and was not associated with perinatal infection.