Factors related to fertility play crucial, but often unappreciated, role in influencing health, aging and lifespan of women. Pregnancy, lactation and childcare are energetically expensive, especially in women with high lifetime reproductive effort and particularly those who are in poor nutritional status. Allocation of resources to support reproduction may cause their insufficient supply to other metabolic functions, resulting in compromised physiology, increased risks of diseases and, consequently, a reduced lifespan. Variation in health, aging and longevity among women may, therefore, be partially explained by differences in their lifetime reproductive effort. I present an overview of a conceptual and methodological approach that could be used when studying tradeoffs between reproduction and aging. It is important to identify biomarkers of health and aging processes, account for polymorphism in genes having antagonistic pleiotropic effects and provide detailed description of confounding factors. Factors that may alleviate costs of reproduction (e.g. social status, nutritional status, help provided by neighbors and relatives) magnify physiological variation among subjects and should be explicitly controlled in statistical models. Preliminary results of the FEM-AGING study conducted in rural Poland that utilizes this methodological approach will be presented.