Benefits of breast-feeding to both mother and baby are widely recognized (1,2). They include nutritional superiority of breastmilk over artificial milk (3,4), transmission of antibodies and immunizational properties to the baby for prevention of disease (5), lower incidence of allergies in breastfed infants (1,6), prevention of haemorrhage during the early postpartum period for breast-feeding mothers and prevention of ovulation (2). Potential role of breastfeeding in birth-spacing contributes to better health for newborn infants and older siblings (2,7). Recently, the Lactational Amenorrhoea Method (LAM) has been advocated as a natural method for contraception until menses returns or food supplements are introduced or up to six months postpartum (8).
In 1990, the Innocenti Declaration to promote breastfeeding worldwide was made by the World Health Organization (WHO) and the United Nations Children's Fund (UNICEF). It called for breastfeeding all babies for at least two years. At present, most babies in developing countries are given breastmilk (9). However, the time of initiation, duration, and supplementation vary widely (10). The time of supplementation also affects the duration of breast-feeding. In a four-country study on 4,469 breast-feeding mothers, over 50% were supplementing when the infants were two months old; those who supplemented earlier weaned earlier (9). The primary reasons for weaning babies earlier were perceptions of insufficient supply of milk or refusal of babies to suckle. With respect to perceived insufficiency of milk supply, women using combined oral contraceptives during breast-feeding may well have experienced a decrease in production of milk and then insufficient supply of milk perceived and/or real (11,12).
In nine Latin American countries, the average duration of breast-feeding ranged from 9.2 months in Brazil to 20.2 months in Guatemala (13). Breastfeeding rates were lower in urban areas and, in general, better-educated women breastfed for a shorter duration than other women.
For 36 mothers in Lima, Peru, the main reason for early weaning was a perception of maternal health problems, such as weight loss viewed as 'debilitating', placing the mother at risk for serious illness (14). Work and time commitments outside the home led to early weaning in Peru, Malaysia, and the Caribbean region (14,15). Women surveyed in the latter two areas supplemented before returning to work, because they reportedly thought that permission to return to work would be denied if they were fully breastfeeding. Conversely, in the Congo (then Zaire), few women worked for pay, and the duration of breast-feeding was longer than in Malaysia and the Caribbean region (15). In Nigeria, women working for pay began weaning their infants when the infants were 3-4 months of age, while self-employed or unemployed women began when the child was aged 5-6 months (16).
Results of research on duration of breast-feeding and concurrent contraceptive use indicate that an inverse relationship generally exists (17). In Bangladesh, duration of breast-feeding was compared among women using different types of modern contraception, such as hormonal injection, combined oral contraceptives (estrogen with progesterone), intrauterine device (IUD), and tubal ligation (18). Injection and non-hormonal methods were apparently not related to duration of breast-feeding, but oral contraceptives were associated with earlier weaning. In Taiwan, use of oral contraceptives led to shorter duration of breast-feeding than did the use of other contraceptives or no contraception (18). Another study compared duration of breast-feeding among women using oral contraceptives, injection, and IUD in Africa, Latin America, and Asia (19). The findings indicated that women using oral contraceptives breastfed for a shorter duration, while the use of other contraceptives did not affect the duration of breast-feeding. …