Measurements
All details of maternal and neonatal conditions during pregnancy and delivery were obtained from the hospital information systems. After applying the inclusion and exclusion criteria, we invited mothers for a clinical visit within 6 weeks after delivery and encouraged them to participate in our questionnaires, including EPDS, Leakage Index Questionnaire, and Pain Scale (Numerical rating scales).
EPDS is the most commonly-used PPD scale worldwide and is one of the most authoritative self-evaluation scales to screen for PPD.20 Each of its 10 items is divided into 4 grades and scored from 0 to 3. The total score ranges from 0 to 30, with higher scores signifying more serious PPD21. Compared to other questionnaires, it has a satisfactory diagnostic efficiency and is more concise to subjects.22 The sensitivity of EPDS has been proven to range from 0.67 to 1.00, and the specificity is consistently 0.87 or higher when the cut-off value is 13.23 Therefore, a score of EPDS ≥13 was determined to be positive for PPD screening in our study.
The Leakage Index Questionnaire (involving 3 items with multiple choices) and Pain Scale were used to evaluate the recovery of muscles in the pelvic floor and the degree of postpartum pain in mothers respectively. The scores of the former range from 0 to 6 and from 0 to 10 in the latter. The higher scores on the Leakage Index Questionnaire predict poorer recovery of pelvic floor muscles. Moreover, educational background, annual family income, and milk feeding methods were also investigated in our questionnaire (details are shown in Figure S1).