The purpose of this descriptive research was to describe the developmental tasks of expectant fathers during the pregnancy of their wives. The conceptual framework of this study was the developmental tasks of expectant fathers during the pregnancy of their wives, developed by May and Mahlmeister. It consisted of five tasks which were accepting the pregnancy

establishing a relationship with the unborn child

adjusting to changes in self

adjusting to changes in the couple relationship

and preparing for labor, birth, and early parenthood. Moreover, the researcher added in each task some detailed feelings and behaviors reviewed from other related literature and research findings. The samples, purposively selected, were 180 expectant fathers of the first child whose wives attended prenatal care at Lampang Hospital from September to October 1997. The research instrument was the questionnaire developed by the researcher consisted of close-ended and open-ended questions related to the demographic data and the developmental tasks of the expectant fathers during the pregnancy of their wives. The content validity of the developmental tasks questionnaire was examined by seven experts. The content validity index was 0.84. The reliability tested by using Cronbachs coefficient alpha was 0.88. Data were collected by the researcher and analyzed by using frequency, percentage, mean, standard deviation, and content analysis. The findings showed that :- 1. The mean scores of all five developmental tasks of the subjects had moderate levels ( = 2.79-3.32, SD = 0.34-0.53). The task of establishing a relationship with the unborn child was the highest mean ( = 3.32, SD = 0.46). From the open-ended questions, some selected feelings or behaviors of each task occurred in different time, during prepregnancy and during pregnancy period each trimester. 2. Most mean scores of the subjects feelings and behaviors of each task were moderate levels. The highest means were feeling happy when dreaming of the unborn child who has been growing up ( = 3.67, SD = 0.57), feeling concerned about the health of the unborn child ( = 3.83, SD = 0.42), accepting the changing in bodily structure and development and emotion of their wives as the normal condition in pregnancy women ( = 3.40, SD = 0.70), and waiting for the baby to be born and having confidence to become good fathers have the same mean scores ( = 3.70) but have different SD. The former is 0.56, while the latter is 0.65. The findings, analyzed by using content analysis, showed more feelings and behaviors besides the documentary literature involved. The implication of this study in nursing practice is to promote the developmental tasks of expectant fathers during the pregnancy of their wives. The knowledge gained can be applied to related educational and research programs. It is recommended that qualitative and longitudinal study with an emphasis placed on adaptation process of expectant fathers during the pregnancy of their wives should be conducted. This study should be replicated with more representative samples of Thai men. Additionally, revision of the developmental tasks questionnaire for higher quality is recommended.