Policy support and trend
In order to promote the research and development of innovative drugs in mainland China, the Chinese government has implemented the new priority review and approval procedure in 2015. Since 2016, the NMPA started evaluating the quality and efficacy of generic drugs in order to further reform and optimize drug innovation and improve the efficiency of drug clinical trials. In 2018, the 60-day Investigational New Drug Application System was officially adopted28-33. In 2020, the NMPA issued an announcement on three documents, including the review procedures for breakthrough therapeutic drugs, the review and approval procedures for the conditional approval of drug marketing applications, and the priority review and approval procedures for drug marketing authorization34.However, the results of our study suggested that there is no significant change in the number of trials regarding pregnancy drugs compared to the fast growing number of anti-cancer drug trials. From 2009 to 2018, the annual growth rate of anticancer drug trials in mainland China was 33%35. The long-term follow-up assessment and enrollment are challenging whereas the return and benefit are small, and there is a lack of established laws and regulations to promote the development of drugs for pregnant women. Prospective pregnancy registries to monitor drug-related adverse reactions and follow-up throughout pregnancy are a feasible approach. For example, the North American Anti-Epileptic Drug (NAAED) Pregnancy Registry (http://www.aedpregnancyregistry.org/) and the National Pregnancy Registry for Antidepressants (NPRAD (https://womensmentalhealth.org/clinical and-research-programs/) are the kind of website for registration and follow-up.In our study, we found six similar clinical studies in which the registered drugs were Levofloxacin, botulinus toxin, doxycycline, ribavirin, insulin and levothyroxine. It may be an important potential study direction in the future by establishing a collaborative research network for clinical trials to collect obstetric clinical practice information through electronic medical systems.