Fetal heart rate and neonatal condition related to epidural analgesia in women reaching the second stage of labour.

The relationship between epidural analgesia and a number of labour and delivery factors, relevant to fetal and neonatal condition, was considered in a prospective study of 200 labours reaching the second stage of labour. The group was representative of the hospital population with regard to the proportion of nulliparous women, the incidence of instrumental vaginal deliveries and the incidence of epidural analgesia (37%). The 8% of labours requiring fetal blood sampling during the first stage, and the labours with fetal heart rate (FHR) decelerations in the hour prior to second stage (25%) and during pushing (50%) were significantly more likely to have been given an epidural. Nulliparity (55%), induced labour (34%), a first stage longer than eight hours (37%), a second stage longer than 60 min (43%), maternal pushing for longer than 36 min (50%), forceps delivery (28%) and a 1 min Apgar score less than 7 (12%) were also factors associated with significantly higher rates of epidural analgesia whereas meconium (15%), a small baby (16%) and umbilical arterial metabolic acidaemia (13%) were not. FHR decelerations in labours reaching the second stage with an epidural reflect adjustments to fetal cardiovascular control and not acidaemia.