Overall findings
As of June 30, 2020, the number of trials registered in the Drug Clinical Trial Registration and Information Disclosure Platform was 10,856, and the number of trials related to pregnancy drugs was 29 (0.27%), of which only 6 trials recruited pregnant or parturient women. These trials included phase II and phase III, and the effectiveness and safety of these drugs for the mother were the endpoints. There were no pre-planned pharmacokinetic assays. The other 23 clinical trials where the investigational drugs’ indications included pregnancy related diseases, but did not enroll any pregnant women. Interestingly, most of them (18/23) were bioequivalence (BE) test and human pharmacokinetic test. There were 2 trials set the maternal or fetal outcomes as the primary endpoint. All trials on this platform used randomized parallel or cross-over grouping design. The number of trials registered in the ”ChiCTR” was 33,649, and the number of trials enrolling pregnant women was 88 (0.26%). All of them were post-marketing studies, including observational studies or interventional studies. Of the 88 studies, 63.6% (56/88) were randomized parallel controls, 17.0% (15/88) were cohort studies, 4 studies were cross-sectional designs, and 14.7% (13/88) did not indicate randomization. Of these trials, 77.3% (68/88) set both maternal and fetal outcomes as the primary endpoint.Annual numbers of pregnant drug clinical trials by study phase from those two registered platforms were shown in figure 2.