Breast-feeding and return to fertility: clinical evidence from Pakistan, Philippines and Thailand.Asia Pac Popul J. 1990 Mar; 5(1):45-56.AP
The author reports on studies of the relationship between breast-feeding and fertility in Pakistan, the Philippines, and Thailand. "The accumulated evidence suggests that during the first six months of unsupplemented breast-feeding, if the mother remains amenorrheic, then the breast-feeding stimulus is usually sufficient to postpone the recovery of fertility. Breast-feeding frequency alone is not a useful measure of the breast-feeding stimulus in terms of its ability to predict the return of menses or ovulation."