Feeding upon awakening in breastfeeding and bottlefeeding mothers does not affect the awakening cortisol response

An acute breastfeeding stimulus is generally followed by a transient decrease in cortisol levels in mothers. It is currently not clear whether breastfeeding upon waking up would affect the awakening cortisol response (ACR), a significant increase in salivary cortisol levels occurring within 30-45 min after awakening. In the present study, we measured the amplitude and stability of the ACR in response to infant feeding in women who were exclusively bottle-feeding (n = 16), or breastfeeding (n = 13) or feeding their child solid food (n = 12). The results show that the type of infant feeding did not affect the amplitude and stability of the ACR. Given that the ACR has been reported to reflect physical and psychological well-being, our finding that infant feeding upon waking up might not be a confounding factor in ACR studies on the postpartum population represents valuable methodological information.