Evidence Level
Preliminary
Red raspberry leaf is one of the most widely used herbs in pregnancy worldwide, yet its clinical evidence base is surprisingly limited. Simpson et al. (2001) conducted the most rigorous study — an RCT of 192 first-time mothers randomized to 2 x 1.2g raspberry leaf tablets or placebo from 32 weeks gestation. The treatment group showed a shortened second stage of labor (mean 9.6 minutes shorter) and a lower rate of forceps delivery (19.3% vs 30.4%). An earlier retrospective study by Parsons et al. (1999) of 108 women found similar trends. Both studies found no adverse effects on mother or baby. Despite encouraging results, the evidence base requires larger, multi-center trials to make definitive claims.