The World Health Organization Multinational Study of Breast-feeding and Lactational Amenorrhea. I. Description of infant feeding patterns and of the return of menses. World Health Organization Task Force on Methods for the Natural Regulation of Fertility.
OBJECTIVE
To detect differences between populations in both infant feeding practices and the duration of lactational amenorrhea, if they exist.


METHODS
Prospective, nonexperimental, longitudinal follow-up study.


METHODS
Five developing and two developed countries.


METHODS
Four thousand one hundred eighteen breast-feeding mothers and their infants.


METHODS
Breast-feeding women collected ongoing information about infant feeding and family planning practices, plus the return of menses. Fortnightly follow-up occurred in the women's homes.


METHODS
Breast-feeding frequency by day (and by night); 24-hour breast-feeding duration, percent of all infant feedings that were milk/milk-based (and solid/semisolid foods); time until the end of full breast-feeding; time until regular supplementation; and time until the end of lactational amenorrhea.


RESULTS
Differences between the centers in the duration of amenorrhea were substantial, ranging from a median of 4 months in New Delhi (India) to 9 months in Chengdu (China). Women in developed countries (but also women in Chengdu) were more likely to delay supplementation (for up to 5 months), whereas women in Santiago (Chile), Guatemala City (Guatemala), and Sagamu (Nigeria) started supplements much earlier, sometimes as early as 1 week after birth.


CONCLUSIONS
Both breast-feeding behavior and the duration of lactational amenorrhea vary markedly across settings, indicating that breast-feeding promotion and family planning advice should be site- and culture-specific.
D000328:Adult; D000568:Amenorrhea / Q000503:physiopathology*; D001942:Breast Feeding; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007227:Infant Nutritional Physiological Phenomena; D007231:Infant, Newborn; D007391:International Cooperation; D007774:Lactation / Q000502:physiology*; D008597:Menstrual Cycle / Q000502:physiology*; D011446:Prospective Studies; D014944:World Health Organization