Recognizing the importance of health care during the perinatal period, the topic for this issue of "Children in the Tropics" is prenatal development; this issue is intended for health educators for use in educating their clients about prenatal development, health care during pregnancy, labor and delivery, and the needs of the mother and neonate during the perinatal period. The sections are: (1) "Gestation," focusing on considerations for health care providers, psychological, social, and environment risk factors; (2) "Intrauterine Development," presenting a day-by-day account of organ formation and development, functions of the placenta, the amniotic fluid, methods of intrauterine stimulation, medication, drugs, and maternal diet; (3) "Surveillance of Pregnancy," detailing health care procedures and the impact of the expectant mother's family and social environment; (4) "Pregnancy and Childbirth: A Psychological and Physiological Experience," describing psychological needs during pregnancy, the role of the health team, physical and psychological aspects of childbirth, examination of the neonate, identifying gestational age, and breastfeeding; and (5) "The Health Team--An Interdisciplinary Team," presenting the educational needs of expectant mothers and their families and health care procedures during the perinatal period. An appendix describes the effects of specific drugs taken at various points during prenatal development, during labor, or while breastfeeding. (KB)