NR3C2 and sleep disorder: The above results suggest that sleep disorders of mothers in the third trimester of pregnancy can lead to decreased expression of MR, resulting in elevated cortisol levels to activate an increased number of GRs that result from down-regulation of NR3C2 promoter methylation to increase the risk of postpartum sleep disorders [30, 31], and then maternal postpartum sleep disorder could increase infants sleep disorder in turn.