Reference guides for the safe use of drugs during pregnancy: a systematic review and comparative analysis.

Purpose: To comprehensively evaluate and compare all the available reference guides for the safe use of drugs during pregnancy, with the goal of determining the scientificity and reliability of these reference guides.

Methods: We searched PubMed, EMbase, CNKI, Wanfang Database, and VIP database to comprehensively identify the available reference guides. Moreover, we selected 103 drugs based on relevant literatures, and compared the recommendations of each drug from different reference guides.

Results: A total of 14 available reference guides were identified. However, none of these reference guides assessed the risk of bias of original studies or the quality of current evidence. Seven reference guides adopted expert consensus method to formulate pregnancy recommendations, while the rest reference guides did not report the formation method. Moreover, 77.7% of the selected drugs had inconsistent recommendations among different reference guides. In addition, the referenced human and animal studies for the same drug differed among different reference guides.

Conclusion: Our results indicate that current reference guides for the safe use of drugs during pregnancy are less scientific and reliable, and there are considerable discrepancies in recommendations from different reference guides concerning drug use during pregnancy. The reasons for the discrepancies in recommendations include ① the literature search in most reference guides was not comprehensive, ② none of the available reference guides assessed the risk of bias of original studies or the quality of current evidence, and ③ the method adopted by current reference guides to formulate recommendations had obvious subjectivity and lacked of scientificity.