If you’re a woman who has been pregnant or anyone who works in labor and delivery/perinatal care, you may have heard of this popular herbal therapy. Raspberry leaf – commonly consumed in tea form. It’s a centuries old herbal therapy – said to have effects on contractions that increase their strength and effectiveness, and shorten the length of labor. Claims have also been made that it ripens the cervix, and relieves nausea in pregnancy.
But are these claims based in fact? Is it safe to use in pregnancy? Let us explore this a little bit more.
*Disclaimer: This blog is intended for informational purposes only. The information on this blog should not be used as a substitute to medical advice or medical treatment. As always, your Primary Care Provider, a doctor, or another health professional is your best resource for specific questions and medical advice. If you believe you or a loved one are experiencing a medical emergency, please contact 911.*
What do and don’t we know about this therapy?
First of all, I can tell you that it is understudied. This is common with women’s health subjects, especially relating to pregnancy due to the ethical challenges of studying this population (and also y’know, gender bias). A quick search in the literature brings up very little data, especially anything very recent. I was able to find a few sources – one being an older review from 2009, which also concluded that there was limited research on the therapy.
There was one clinical trial done with humans found by the review, dating back to 2001. A small sample of pregnant women was studied – one group had raspberry leaf tablets twice daily from 32 weeks forward and the other had a placebo tablet. Results showed no significant differences between the groups in regards to C-section rates, pain relief needed during labor, or need for augmentation of labor. Labor was about 9.6 min shorter in length for the group that received the raspberry leaf tablets, however it was not considered to be statistically significant.
Notably, the two human studies they reviewed showed no side effects from the use of raspberry leaf during pregnancy – but the authors highlight the fact that both human studies had sample sizes of under 100 people (which is not representative of the population and therefore, not necessarily a reliable result).
The review found that there were mixed results from animal experimentation with raspberry leaf in regards to its effects on the uterus. Overall, their conclusion was – dun, dun, dun…. – that more studies are needed.
I tried to look for more studies and was able to find very little. I found one article from 2016 from Midwife Today where the midwife concluded, after looking at this same review (and one other study from 2010), that although she used the leaf during her own pregnancy and had yet to see any negative effects in women from it, she would not recommend it to any patients until more studies are done on its safety.
The most recent article I could find that examined the use of raspberry for labor induction and/or augmentation was from 2019 and it was still citing studies from prior to 2001 with the same conclusions – results are up in the air because there are very few studies on the subject, and the ones that exist have limited sample populations.
One thing is known for sure: the use of raspberry leaf, and many other herbs, can of course be a cultural norm, passed on through generations. This same article mentions that there is however, often a misunderstanding that natural = safe.
So, this herb has been used for a long time, appears to be generally safe in regards to side effects (based on the limited data that is available + experiences from providers and moms), however there is a serious lack of evidence regarding both its safety AND its efficiency at doing what people claim it does. More studies are needed!
So what’s the verdict on raspberry leaf?
I point you back to the paragraph above, and I also point you in the direction of your primary care provider. Ask for their advice – don’t be afraid. I always, always highlight this but your healthcare professional is there to help you and provide advice (if that is in their scope of practice) and guidance.
Right now, there is only a little evidence that it is beneficial and flimsy evidence that it is safe – as you can see, small “differences” were seen in time but it was 9 minutes and it was not deemed to be significant.
Risks appear to be low, but again, this is based on firsthand accounts/experiences and studies that are not representative or recent (I also didn’t see any longitudinal studies – looking at changes/impact overtime in mom and/or baby – this would certainly be something important to look at, to me anyways).
I repeat: more studies are needed. Discuss with your provider if you have questions specific to your situation. And always report to your provider and/or pharmacist any herbal treatments you are taking when they ask for medical history – these can have interactions with other medications, and risks during pregnancy! Better yet – don’t take anything without first consulting your provider to make sure it is safe for you and your baby.