Breast-feeding and plasma oxytocin concentrations.

Abstract

Summary and conclusionsThe patterns of response of oxytocin to a breast feed were studied in 10 mothers in the first week post partum. The initiation of lactation did not appear to be related to release of oxytocin. In established lactation an oxytocin response did not appear to be essential for adequate milk flow and did not occur always at the time of peak milk flow. The only factor identified that positively correlated with release of oxytocin was multiparity. In those subjects who showed a response the hormone was released in surges, some of which persisted in the circulation for less than one minute.These findings cast some doubt on the conventional view that release of oxytocin is essential for satisfactory milk flow during breast-feeding.

Breast Stimulation in Cycling Women, Pregnant Women and a Woman With Induced Lactation: Pattern of Release of Oxytocin, Prolactin and Luteinizing Hormone

“…In the present study we confirmed that nipple stimulaticn (touch and pressure) released OTin two of five normal cycling women. The rise in OT was brisk, comparable in magnitude to that found in post-partum breast-feeding women (Lucas et al, 1980;Weitzman et al, 1980;Dawood et al, 1981;Leake et al, 1983;McNeilly et al, 1983;Johnston & Amico, 1986) and occurred without prior conditioning or the physiological events which accompany post-partum lactation. The reason for the lack of response of OT in three of five women was not determined in this study but could not be attributed to differences in stage of the menstrual cycle because all women were studied in the luteal phase.…”

“…The reason for the lack of response of OT in three of five women was not determined in this study but could not be attributed to differences in stage of the menstrual cycle because all women were studied in the luteal phase. Although OT increased significantly during nipple stimulation of pregnant women in the third trimester, the magnitude of the OT response was diminished compared to that in normal cycling or post-partum breast-feeding women (Lucas et al, 1980;Weitzman et al, 1980;Dawood et al, 1981;Leake et al, l983,1984aLeake et al, l983, , 1984bMcNeilly et al, 1983;Johnston & Amico, 1986) and may have been due to the hormonal milieu of pregnancy. PRL release did not correlate with OT release in any circumstance studied and was in agreement with what has been found in post-partum women also (McNeilly et al, 1983;Johnston & Amico, 1984, 1986.…”

“…Breast stimulation in post-partum women results in the following hormonal changes: increases in oxytocin (OT) and PRL; low levels of progesterone, oestradiol and LH; and in a majority of women, absence of the pulsatile secretion of LH (Noel et al, 1974;Lucas et al, 1980;Weitzman et al, 1980;Dawood et al, 1981;Leake et al, 1983;McNeilly et al, 1983;Poindexter et al, 1983;McNeilly, 1984). Effects of the hormonal changes include milk production (secondary to release of PRL), milk ejection (secondary to release of OT), and amenorrhoea and anovulation (secondary to low levels of ovarian steroids and gonadotrophins).…”

Retracted: A meta‐analysis and theoretical critique of oxytocin and psychosis: Prospects for attachment and compassion in promoting recovery

“…OXT is a neuromodulatory neuropeptide, which is produced in the hypothalamus and is important for the processing of emotional stimuli in a social context, thus allowing the initiation of prosocial behaviours and mediating the effects of social bonds on coping. OXT has been increasingly understood to be associated with maternal behaviour in response to infant cues (Lucas, Drewett, & Mitchell, 1980;Uvnas-Moberg, Bruzelius, Alster, & Lundeberg, 1993), social cognition, and affiliative behaviour (Insel, 2010), and the formation of social and spatial memories, affiliative behaviour, and emotion regulation (Ferguson, Young, & Insel, 2002).…”

Neuromodulation of maternal circuits by oxytocin

“…During nursing, plasma oxytocin levels peak at slower timescale in the order of several minutes (Dawood et al, 1981; Lucas et al, 1980; Weitzman et al, 1980) and follow a pulsatile pattern (Freund-Mercier et al, 1988; Jonas et at, 2009). In human mothers, periods of massage-like hand movements performed by the baby prior to suckling are followed by an increase in maternal oxytocin plasma levels lasting for several minutes (Matthiesen et al, 2001).…”