Breastfeeding is a major factor in child growth and very effective as a birth-spacing method, yet its use is still low in developing countries. This study examined the impact of socio-demographic factors on the reported low usage of breastfeeding as a child-spacing method. The study utilized the combination of Max Weber's Social Action Theory and Ajzen and Fishbien's Theory of Reasoned Action as its theoretical framework. Three hundred and thirty-eight copies of a structured questionnaire were administered to nursing mothers. Additional data were collected through qualitative method, such as in-depth interview. A total of 71.4% of the nursing mothers who had post-secondary education had a higher knowledge of exclusive breastfeeding (EBF) as a contraceptive, while 68.8% of the women with lower income would likely use EBF as a contraceptive. A total of 45.4% of the nursing mothers were using EBF as contraceptive, while 31.5% were complementing it with other family planning methods. Socio-demographic factors such as age, income, education and ethnic membership affected the use of EBF as a contraceptive. Suggestions for intervention include health education, especially during antenatal/postnatal sessions and aggressive advocacy on the effectiveness of EBF.