Due to the fact that most breastfeeding research has been carried out by those in the natural and health sciences, the literature has emphasized the health benefits of breastfeeding for babies and how to persuade women to do it. Far less research has come from sociologists and rarely has it examined potential costs of breastfeeding for some women. After struggling to juggle breastfeeding and working, I, along with my co-researcher Mary C. Noonan, began researching the socio-economic implications of infant feeding for women's lives. We carried out linear growth models using the National Longitudinal Survey of Youth in the United States to assess if there are differences in the trajectories of women's earnings over time depending on whether the women breastfed for a long duration, a short duration or not at all. Our initial presentations of results led to some resistance and criticism. Both the critiques and our responses to them raise interesting questions about the nature of science and point to the importance of a rigorous attention to detail when carrying out quantitative research.