Negative Feedback in GnRH Physiology	

The stimulating actions of GnRH interact with the effects of the gonadal steroids and with peptide secretions of the gonads – termed inhibins. Under particular circumstances, oestrogens sensitise the pituitary to the stimulating effects of GnRH (the mechanism underlying the mid cycle ovulatory surge), but can also inhibit GnRH responsiveness. 
Important negative feedback effects on the gonadotroph cells are exerted by the inhibins which selectively inhibit FSH secretion but not LH secretion.