The birth of a baby should be a very special time for every woman, but perineal pain can sometimes interfere and cause problems. The perineum is a diamond-shaped area between the vagina and the anus. Perineal pain can arise from bruising or tearing that sometimes occurs as the baby is born. Pain can also arise from a cut which may be used to enlarge the perineal outlet for the baby to be born (episiotomy). Episiotomies require stitches (also called sutures), and natural tears also may need stitches. Any trauma and stitches can cause discomfort and pain. In addition, there is often pain if forceps or ventouse have been used to help the baby into the world. Reducing the chance of perineal trauma and thus perineal pain is clearly important for women. However, this review is part of a series of reviews looking at drugs to help relieve perineal pain once it is there in the early days after the birth. This review identified 10 studies, involving 1367 women, looking at how effective paracetamol might be in helping with this pain. The studies were quite old and thus not of high quality. However, they showed that paracetamol (either in a single 500 mg to 600 mg or a single 1000 mg dose) was effective at reducing the perineal pain, mostly caused by episiotomies. The studies did not look carefully at potential adverse effects but generally paracetamol at these doses causes few problems. There are also generally no identified problems for breastfed babies when mothers take paracetamol, but these outcomes were not specifically assessed in any of the included studies. The comparison of how effective paracetamol is compared with other drugs is being assessed in the other reviews in the series.
More women experienced pain relief, and fewer had additional pain relief, with paracetamol compared with placebo, although potential adverse effects were not assessed and generally the quality of studies was unclear.
Perineal pain is a common but poorly studied adverse outcome following childbirth. Pain may result from perineal trauma due to bruising, spontaneous tears, surgical incisions (episiotomies), or in association with operative births (ventouse or forceps assisted births).
To determine the efficacy of a single administration of paracetamol (acetaminophen) systemic drugs used in the relief of acute postpartum perineal pain
We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 6 November 2012.
Randomised controlled trials (RCTs) assessing paracetamol (acetaminophen) in a single dose compared with placebo for women with early postpartum perineal pain. We excluded quasi-RCTs and cross-over studies.
Two review authors assessed each paper for inclusion and extracted data. One review author reviewed the decisions and confirmed calculations for pain relief scores.
We did not identify any new trials from the updated search so the results remain unchanged as follows.
We have included 10 studies describing two dosages of paracetamol. Of these, five studies (526 women) assessed 500 mg to 650 mg and six studies (841 women) assessed 1000 mg of paracetamol. We chose to use random-effects meta-analyses because of the heterogeneity in dosage used. Studies were from the 1970s to the early 1990s, and there was insufficient information to assess the risk of bias adequately, hence the findings need to be interpreted within this context.
More women experienced pain relief with paracetamol compared with placebo (average risk ratio (RR) 2.14, 95% confidence interval (CI) 1.59 to 2.89, 10 studies, 1279 women). In addition, there were significantly fewer women having additional pain relief with paracetamol compared with placebo (RR 0.34, 95% CI 0.21 to 0.55, eight studies, 1132 women). Both the 500 mg to 650 mg and 1000 mg doses were effective in providing more pain relief than placebo.
Maternal and neonatal potential adverse drug effects were not assessed in any of the included studies. Indeed few secondary outcomes were assessed.