The impact of intrapartum analgesia on labour and delivery outcomes in nulliparous women.

OBJECTIVE:

To determine if nulliparous women intending to have epidural analgesia have a similar labour profile and delivery outcome to women who intend to have their labour managed using alternative forms of pain relief.

MATERIALS AND METHODS:

A prospective randomised controlled clinical trial conducted at a tertiary obstetric institution. Nulliparous women intending to deliver vaginally with a term singleton fetus were eligible for recruitment.

RESULTS:

1159 women were recruited, of whom 992 were subsequently randomised to receive continuous midwifery support (CMS) or epidural analgesia (EPI) on presentation for delivery. The duration of labour was shorter in the CMS group compared with EPI (10.7 hours (inter quartile (IQ) 7.0,15.2) versus 11.4 hours (IQ 8.2,15.2), p = 0.039). The median duration of the first stage was 8.9 hours (IQ 6,12.5) versus 9.5 hours (IQ 7,12.7) (p = 0.069), and the median duration of the second stage was 1.33 hours (IQ 0.6,2.5) versus 1.48 hours (IQ 0.77,2.6) (p = 0.034). The requirement for oxytocin augmentation in spontaneous labour was 39.8% CMS versus 46.2% EPI (p = 0.129). There was no significant difference in the caesarean section rates. The need for any operative delivery was significantly lower in CMS (43.9% CMS versus 51.5% EPI, p = 0.019).

CONCLUSIONS:

Nulliparous women have a high usage of epidural analgesia, regardless of their prelabour intentions. In women who do not intend to use epidural analgesia, the temporal delay in insertion compared with those who use epidural analgesia as their primary analgesic modality is associated with a small but statistically significant reduction in overall labour duration and operative delivery rates.