Ethanolic extract of the defatted roots ofB. chitria was chromatographed when a compound-I (C21H25O5N) characterised as dihydropalmitinium hydroxide was isolated. Chronic administration of DPH for 20 days reduces the weights of ovary, uterus and vagina in normal cycling gerbils. Atresia of the large follicles and vacuolization of follicular cells was conspicuous. The luteal cells and endometrial glands were shrunken. Vaginal smear showed prolonged diestrous cycle reflecting suppression of estrogenic activity. Simultaneous administration of oestradiol dipropionate and DPH to spayed gerbils failed to maintain the growth of uterus and vagina. DPH treatment to intact/spayed/pregnant gerbils inhibited protein synthesis and decreased the sialic acid and glycogen contents of the genital tract. Serum protein was low whereas serum sialic acid, cholesterol, phospholipids, triglycerides and NEFA did not change. Antioestrogenic activity of the compound is discussed. Abortifacient action of DPH is of great significance in fertility regulation using plant products.