An indigenous contraceptive herbal formulation consisting of a mixture of Lepidagathis longifolia, Palaquium sp and Phyllagathis rotundifolia is being used by the Temuan Aborigins of Malaysia. Although the previous studies demonstrated that this contraceptive herbal formulation causes anovulatory estrous cycle, altered circulating hormone levels and fetal resorption in rats, but the effects of this formulation on the gonadotrphs of the pituitary gland are yet to be evaluated. The present study was designed to observe the morphometric changes of the gonadotrophs and the plasma concentrations of follicle stimulating hormone and leutinizing hormone. Thirty five Sprague-Dawley adult female rats were randomly divided into 5 groups. Experimental animals were given a combined herbal extract or individual herbal extract at a dose of 540 mg/kg/day subcutaneously for 7 days. Immunostained gonadotrophs were studied by using image analyzer. FSH and LH serum concentrations were determined using RIA. The FSH and LH concentrations were low in animals that received combined herbal extract (p<0.01). FSH concentration was noted to be significantly low in animals that received P.
rotundifolia (p<0.05). The mean cell area and cell density of gonadotrophs of animals that received combined herbal extract were significantly low compared to control group (p<0.05). It was concluded that the herbal extracts do suppress the production of gonaotrophins along with the demonstrable suppresive effect on the FSH cells.