Quesnel, H., Ramaekers, P., van Hees, H. and Farmer, C. 2013. Short Communication: Relations between peripartum concentrations of prolactin and progesterone in sows and piglet growth in early lactation. Can. J. Anim. Sci. 93: 109-112. Postpartum hypogalactia has been suggested to be related to an impaired secretion of prolactin or to elevated concentrations of progesterone around farrowing. In the current study, peripartum circulating concentrations of prolactin and progesterone were determined in 50 multiparous sows (parities 1 to 5) and related to the Na K^-1 ratio and lactose in colostrum and to piglet growth in early lactation. An effect of parity (P<0.001) was observed for prolactin, with sows from parity 1 having lower concentrations than sows from parities 2, 3, 4 and 5, and sows from parities 4 and 5 having the greatest concentrations. Piglet growth from day 1 to day 5 was negatively correlated with progesterone concentrations in sows on day 1 (r=-0.36, P=0.01). The present study supports the hypothesis of a negative impact of high concentrations of progesterone after farrowing on early growth of piglets and also shows a clear effect of sow parity on the peripartum concentrations of prolactin suggesting that younger sows are more vulnerable to reduced milk yield due to lower prolactin concentrations.