CYP19A1 and preeclampsia: E1/A4 was reduced in the PE group (48.77 vs. 54.93, p = 0.42) in our research, and similarly, it was found to decrease significantly in another study (Berkane et al., 2018), suggesting a deficiency of placental aromatase in preeclampsia, which might not be at the transcriptional level but rather at the level of posttranscriptional modification and regulation.