摘要Objective To determine the relation between infant feeding practices (and other fac-tors) and the duration of postpartum amenorrhoea in a sample of Chinese womendinally in 541 mothers and their infants in Pengxian County Sichuan Province. The,durations of breast feeding and of lactational amenorrhoea were estimated throughsurvival analysis. Cox's non-parametric hazards regression analysis was performed todetermine thevariables associated with the duration of lactational amenorrhoea.Results Mothers breast fed frequently per day, the mean frequency ranging from 6. 4per day at 3 weeks postpartum to 5. 4 per day at 6 months. They breast fed for over18. 3 monthson average. The median duration of lactational amenorrhoea was 9. 3months. Theperiod from birth until the first breast feed was a significant determinantof the duration of lactational amenorrhoea, P = 0. 038. Compared with women whoended full breastfeeding earlier, those who ceased full breast feeding at 120 to 24Cdays returned to menses significantly sooner (risk ratio ＝ 1. 34; 95% CI = 1. 06～1. 69). This finding is probably spurious since no relationship between full breast feed-ing duration and the return of menses was found among women who ended full breast-feeding after 240 days.Conclusion The most important determinant of the return of menses was the delay inthe first breast feed after birth, suggesting that the Ten Steps to Successful Breast feed-ing should be more precisely implemented.