Analgesia for labour pain – analysis of the trends and associations in the Grampian region of Scotland between 1986 and 2001

BACKGROUND: Although intrapartum analgesia has been in use since Victorian times, there have been few attempts to study its usage from routinely collected data. This population based epidemiological study aimed to analyse retrospective data on the distribution of different types of labour analgesia used by women in the Grampian region of Scotland between 1986 and 2001 in order to examine time trends and associations. METHODS: Data records on all deliveries occurring in the years 1986 to 2001 were extracted from the Aberdeen Maternity and Neonatal Databank. The rates of the use of epidural, opioid and Entonox or no analgesia for pain relief in labour in each year were calculated. Maternal, pregnancy, labour and delivery characteristics were compared among the users of three different analgesics by univariate and multivariate analyses. RESULTS: A total of 81,418 deliveries were analysed. Of these, 12,659 (15.5%) women had epidural, 33,819 (41.5%) had used opioids and 26,974(33.1%) received either Entonox or no analgesia at all. The women who received epidural analgesia were younger, shorter and heavier and had larger babies (OR = 1.05, 95% CI 1.01, 1.08). Three quarters of them were primigravidae and had longer periods of gestation. They were also more likely to have suffered pregnancy related complications (OR = 2.11, 95% CI 1.8, 2.4). Labour was more likely to have been induced (OR = 2.8, 95% CI 2.6, 2.9) and to have lasted longer in this group of women. Women in this group were 5 times more likely to have an instrumental delivery (95% CI 4.9, 5.1) and 7 times more likely to have a Caesarean section (95% CI 5.7, 9.3). CONCLUSION: Non epidural analgesia was found to be the most popular choice for pain relief in labour in the Grampian region between 1986 and 2001, although an increase in the uptake of epidural services is starting to occur. The type of labour analgesia used is associated with the epidemiological characteristics of the women's pregnancy, labour and delivery.