Here's a summary of a research study done by Simpson, M. Parsons, M. Greenwood, J. Wade, K (2001):
OBJECTIVE: Many women consume the raspberry leaf herb during their pregnancies in the belief that it shortens labor and makes labor "easier." METHODOLOGY: Because of the paucity of research regarding this herb, particularly in relation to pregnancy and birth, the authors undertook a double-blind, randomized, placebo-controlled trial. The sample consisted of 192 low-risk, nulliparous women who birthed their babies between May 1999 and February 2000 at a large tertiary-level hospital in Sydney, Australia. The aim of the study was to identify the effect and safety of raspberry leaf tablets (2 x 1.2 g per day), consumed from 32 weeks' gestation until labor, on labor and birth outcomes. RESULTS: Raspberry leaf, consumed in tablet form, was found to cause no adverse effects for mother or baby, but contrary to popular belief, did not shorten the first stage of labor. The only clinically significant findings were a shortening of the second stage of labor (mean difference = 9.59 minutes) and a lower rate of forceps deliveries between the treatment group and the control group (19.3% vs. 30.4%). No significant relationship was found between tablet consumption and birth outcomes. CONCLUSION: The lack of significant differences between the groups on measures expected to demonstrate the effect of raspberry leaf ingestion during pregnancy on labor prompted consideration of the issue of effectiveness of dosage level. Suggestions for further research are offered.
Another study by Parsons, M. Simpson, M. Ponton, T. (1999) found that:
The findings suggest that the raspberry leaf herb can be consumed by women during their pregnancy for the purpose for which it is taken, that is, to shorten labour with no identified side effects for the women or their babies. The findings also suggest ingestion of the drug might decrease the likelihood of pre and post-term gestation. An unexpected finding in this study seems to indicate that women who ingest raspberry leaf might be less likely to receive an artificial rupture of their membranes, or require a caesarean section, forceps or vacuum birth than the women in the control group.
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Hope this info helps anyone having a raspberry dilemma!