Scientists from the University of Colorado and Shady Grove Fertility in Colorado report that a survey of 95 women revealed the use of a wide range of dietary supplements, ranging from ginger to echinacea, and including cannabidiol (CBD).
Writing in F&S Reports, the researchers noted that their results, “call for further investigation of clinically relevant supplement interactions with infertility therapies.
“Understanding the use of herbal supplements could guide clinical counseling of patients regarding potential drug interactions with supplements and could also influence education efforts among patients and providers regarding increased disclosure of supplement use.”
The study objective was to measure the patterned usage of dietary supplements, including herbal supplements, and evaluate potential supplement-drug interactions among patients seeking infertility treatment.
The cross-sectional survey study, conducted between January 2021 and July 2021, included 95 reproductive-aged patients (24–45 years). Survey data showed that 68.4% of patients used supplements. Current use of vitamins and herbal supplements was reported by 93.7% and 53.7%, respectively, with the median of 2 (range 19) supplements used per patient.
The most commonly used herbal supplements, in the form of pills/capsules (23.8%) and tea (42.3%), were: green tea, chamomile, peppermint, turmeric, elderberry, ginger, maca, garlic, goji berry, cranberry/echinacea, and cannabidiol (CBD)/Ashwagandha/Ginseng/Vitex/Combination products, to support general health and wellness (24.5%), immune function (16.2%), and stress (14.0%).
Patients reported using maca, chasteberry, goji berry, ginger, yam-based progesterone, and combination products specifically for fertility purposes (15%). Participants reported learning about these supplements from their friends and family (43.9%), the internet (28.0%), alternative medicine providers (20.2%), and general health care providers (7.9%).
Researchers assessed supplement-drug interactions between the most commonly used herbal supplements and the most commonly reported treatments used for infertility: vitro fertilization (26.3%), intrauterine insemination (24.2%), letrozole (16.8%), clomiphene citrate (11.6%), and other hormonal injections (9.5%).
Using the Natural Medicines Interaction Checker, researchers identified 41 moderate-risk, supplement-drug interactions meaning, “Use cautiously or avoid combination; warn patients that a significant interaction or adverse outcome could occur.” The Natural Medicines Interaction Checker is a peer-reviewed scientific database determining theoretical interactions based on the mechanisms of action of herbal compounds and drugs with similar mechanisms of action.
The most common moderate-risk interactions were via CYP3A4 and CYP2C19 inhibition between letrozole and CBD, chamomile, cranberry, echinacea, garlic, and peppermint. The theoretical inhibition could increase levels of both letrozole and herbal supplements, resulting in increased therapeutic benefit as well as increased adverse effects. No moderate-risk interactions were detected between clomiphene citrate and herbal supplements.
The researchers could not assess interactions between commonly used drugs for in vitro fertilization (menotropins, follitropins, gonadotropins) and intrauterine insemination (human chorionic gonadotropin, leuprolide) and herbal supplements because these medications are currently not included in the Natural Medicines Interaction Checker.
The authors stated: “Our study is the first to our knowledge to elucidate the potential for herbal-drug interactions among infertility medications and calls for further clinical studies to be performed to directly assess these interactions.”
Although the study has limitations, they added that “the level of detail we captured with our survey still helps address a major knowledge gap within the field regarding what specific supplements and herbal medicine are commonly used.”
Source: F&S Reports
March 2023, Volume 4, Issue 1, Pages 104-111, doi: 10.1016/j.xfre.2022.12.001
“Herbal supplement use among reproductive-aged women in an academic infertility practice"
Authors: J. Friedman, et al.