Oral herbal medicine for women with intrahepatic cholestasis in pregnancy: a systematic review of randomized controlled trials

BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy complication whose range has been calculated to be between 0.01 and 15.6% all around the world. We wanted to systematically evaluate the effect and safety of oral herbal medicine on treatment for ICP. METHODS: Details of the methods could be found in the registered protocol on PROSPERO (CRD42018096013). Trials assessing the effectiveness of herbal medicine for ICP were searched from seven electronic databases from inception to 28th February 2020. RevMan 5.3 software was used to perform all statistical analysis. Meta-analysis, additional analysis, Trial Sequential Analysis (TSA) and Grading of Recommendations Assessment, Development and Evaluation (GRADE) were conducted if data permitted. RESULTS: Totally 43 randomized controlled trials with 3556 patients were included. Meta-analysis showed potential good adjunctive effect of herbal medicine on decreasing the pruritus scores (MD -0.58, 95% CI − 0.79 to − 0.36), the serum TBA scores (MD − 3.99 μmol/L, 95% CI − 4.24 to − 3.74) on the basis with Ursodesoxycholic acid. Compared to the medicine alone, significantly lower incidence of fetal distress (RR 0.41, 95% CI 0.32 to 0.51), asphyxia neonatorum (RR 0.35, 95%CI 0.25 to 0.49), cesarean section (RR 0.73, 95% CI 0.63 to 0.85), postpartum hemorrhage (RR 0.45, 95% CI 0.28 to 0.72) were observed in the combination group. But the comparison between herbal medicine and medicine showed inconsistent results among trials. Insufficient information could be used to evaluate the safety of herbal medicine for ICP. CONCLUSION: This review found the current evidence may support the effectiveness of combination of herbal medicine and conventional medicine for decreasing the maternal pruritus scores, the serum TBA, and the number of fetal distress, or asphyxia neonatorum events related to this condition (which was supported by TSA results). Since there were obvious statistical and clinical heterogeneity among trials, and the methodological quality of the included studies was poor, the level of the evidence could only be defined as “very low” according to the GRADE criteria. Further high quality studies are still needed to testify the effectiveness and safety of herbal medicine for ICP.