Epithelial cells from the ampulla of healthy oviducts from 16 women aged 33-41 years and at different phases of their menstrual cycles were used to establish primary cultures and the continuation of a cell line. The morphology and behaviour of these cells in vitro were evaluated using Nomarski's inverted optics, scanning and transmission electron microscopy. Cells from all patients produced confluent monolayers in 6-7 days with no significant relationship of cell growth with stage of cycle. Fourteen primary cultures were of the epithelioid type while two showed mixed epithelioid and fibroblast-like growth. Two distinct cell types (ciliated and secretory) were observed in primary culture. Secretory cells showed several microvilli of different lengths and distribution. Secretory cells predominated over ciliated cells in all patients, but maximum ciliation occurred around the time of ovulation. Structural features of the cells in vitro were remarkably similar to those described in vivo. Ampullary cells could be maintained in vitro through four to six passages with 3-4 days of growth between passages. Sub-cultured cells were all secretory and were of two types (I and II) based on ultrastructure. Secretory vesicles containing electron-dense material and lipids were observed in these cells. The method described allows for the use of ampullary cells as feeder layers for IVF and support of cleaving human embryos and the evaluation of the biochemical events surrounding fertilization and ectopic pregnancies.