A role for kisspeptins in pregnancy: facts and speculations.

Kisspeptin is a neuropeptide that was originally discovered in 1996 from a metastasis tumour suppressor gene, KISS1 and was appropriately named metastin. More recently, the discovery of inactivating mutations in the receptor for kisspeptin, a G protein-coupled receptor, GPR54 (KISS1R), have been shown to result in a failure to progress through puberty in man. These findings have led to the kisspeptin/KISS1R system being described as an essential gatekeeper of reproductive function. Recent studies have suggested additional roles of kisspeptin, other than in the central control of the gonadotropic axis including placentation and pregnancy, energy homeostasis and cardiovascular function. Therefore, kisspeptin-KISS1R signalling potentially plays diverse roles in human physiology. Here, we review the literature regarding the role and physiological significance of kisspeptin in pregnancy and highlight some of the key questions that require addressing.