Incidence of severe perineal laceration
Six trials involving 2180 women were included in this outcome, 2143 women contributed data. The result of meta-analysis indicated that women in lubricant group had no statistically difference in the incidence of severe perineal laceration when compared with those in standard care group (RR 0.3, 95%CI 0.05 to 1.88; I2=0%; low due to serious risk of bias and serious imprecision) (Table 1, Figure S19). Subgroup analysis showed that there was not significant subgroup effect between lubricants type subgroups (Pinteraction=0.93) (Figure S20).
When analyzed based on parity, there was not significant in the incidence of severe perineal laceration in lubricant group versus standard care group for nulliparous women (RR 0.28, 95%CI 0.23 to 2.69; I2=0%) (Figure S21). There was insufficient data to perform subgroup analysis for this outcome for multiparous women.