Aspirin (single dose) for perineal pain in the early postpartum period.Cochrane Database Syst Rev. 2020 07 24; 7:CD012129.CD
Perineal trauma, due to spontaneous tears, surgical incision (episiotomy), or in association with operative vaginal birth, is common after vaginal birth, and is often associated with postpartum perineal pain. Birth over an intact perineum may also lead to perineal pain. There are adverse health consequences associated with perineal pain for the women and their babies in the short- and long-term, and the pain may interfere with newborn care and the establishment of breastfeeding. Aspirin has been used in the management of postpartum perineal pain, and its effectiveness and safety should be assessed. This is an update of the review, last published in 2017.
To determine the effects of a single dose of aspirin (acetylsalicylic acid), including at different doses, in the relief of acute postpartum perineal pain.
For this update, we searched the Cochrane Pregnancy and Childbirth's Trials Register (4 October 2019), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (4 October 2019) and screened reference lists of retrieved studies.
Randomised controlled trials (RCTs), assessing single dose aspirin compared with placebo, no treatment, a different dose of aspirin, or single dose paracetamol or acetaminophen, for women with perineal pain in the early postpartum period. We planned to include cluster-RCTs, but none were identified. We excluded quasi-RCTs and cross-over studies.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included RCTs. Data were checked for accuracy. The certainty of the evidence for the main comparison (aspirin versus placebo) was assessed using the GRADE approach.
We included 17 RCTs, 16 of which randomised 1132 women to aspirin or placebo; one RCT did not report numbers of women. Two RCTs (of 16) did not contribute data to meta-analyses. All women had perineal pain post-episiotomy, and were not breastfeeding. Studies were published between 1967 and 1997, and the risk of bias was often unclear, due to poor reporting. We included four comparisons: aspirin versus placebo (15 RCTs); 300 mg versus 600 mg aspirin (1 RCT); 600 mg versus 1200 mg aspirin (2 RCTs); and 300 mg versus 1200 mg aspirin (1 RCT). Aspirin versus placebo Aspirin may result in more women reporting adequate pain relief four to eight hours after administration compared with placebo (risk ratio (RR) 2.03, 95% confidence interval (CI) 1.69 to 2.42; 13 RCTs, 1001 women; low-certainty evidence). It is uncertain whether aspirin compared with placebo has an effect on the need for additional pain relief (RR 0.25, 95% CI 0.17 to 0.37; 10 RCTs, 744 women; very low-certainty evidence), or maternal adverse effects (RR 1.08, 95% CI 0.57 to 2.06; 14 RCTs, 1067 women; very low-certainty evidence), four to eight hours after administration. Analyses based on dose did not reveal any clear subgroup differences. 300 mg versus 600 mg aspirin It is uncertain whether over four hours after administration, 300 mg compared with 600 mg aspirin has an effect on adequate pain relief (RR 0.82, 95% CI 0.36 to 1.86; 1 RCT, 81 women) or the need for additional pain relief (RR 0.68, 95% CI 0.12 to 3.88; 1 RCT, 81 women). There were no maternal adverse effects in either aspirin group. 600 mg versus 1200 mg aspirin It is uncertain whether over four to eight hours after administration, 600 mg compared with 1200 mg aspirin has an effect on adequate pain relief (RR 0.85, 95% CI 0.52 to 1.39; 2 RCTs, 121 women), the need for additional pain relief (RR 1.32, 95% CI 0.30 to 5.68; 2 RCTs, 121 women), or maternal adverse effects (RR 3.00, 95% CI 0.13 to 69.52; 2 RCTs, 121 women). 300 mg versus 1200 mg aspirin It is uncertain whether over four hours after administration, 300 mg compared with 1200 mg aspirin has an effect on adequate pain relief (RR 0.62, 95% CI 0.29 to 1.32; 1 RCT, 80 women) or need for additional pain relief (RR 2.00, 95% CI 0.19 to 21.18; 1 RCT, 80 women). There were no maternal adverse effects in either aspirin group. None of the included RCTs reported on neonatal adverse effects. No RCTs reported on secondary review outcomes of: prolonged hospitalisation due to perineal pain; re-hospitalisation due to perineal pain; fully breastfeeding at discharge; mixed feeding at discharge; fully breastfeeding at six weeks; mixed feeding at six weeks; perineal pain at six weeks; maternal views; or maternal postpartum depression.