There are few studies that have investigated the spiritual problems of couples practicing natural family planning (NFP). The purpose of this paper is to analyze the spiritual problems and interventions of couples who were taught NFP by means of a professional online Web-based support system. Responses from this online system and its forums were categorized according to spiritual responses, spiritual problems, and spiritual interventions to the practice of NFP. Themes addressed included spiritual care in regards to decisions about the transmission of new life, difficulties in dealing with chastity and abstinence, bioethical problems related to pregnancy and illness, end of the reproductive life decisions, ethical treatment of women's health problems, sacrifice, and personal and relational struggles. Online community support, help in building confidence in NFP methods, and bioethicist referral are key interventions. The complexity of these spiritual responses, problems, and appropriate interventions require the expertise of health professionals in cooperation with bioethicists. We concluded that NFP can be viewed as both a spiritual practice and a means of spiritual growth.