Association between Skin-to-Skin Contact and Milk Production
by Anne Eglash MD, IBCLC, FABM
How does skin-to-skin contact impact milk production?
Skin-to-skin contact (SSC) is a well-known strategy to stabilize newborns early postpartum and to improve the likelihood of breastfeeding within the first 2 hours after birth. A landmark study in 2021 demonstrated that immediate SSC for very low birth weight premature infants is associated with decreased infant mortality. Despite the connection between improved breastfeeding rates and improved health among newborns who experience SSC early postpartum, there has not been evidence of the effect of SSC on milk production.
The authors of this manuscript designed a prospective cohort study of 100 medically stable infants born <35 weeks gestation admitted to a level 3 NICU in Florida, USA in 2019-2020. The mothers of eligible infants were asked to document their frequency and duration of SSC, and the caregiver for SSC. Other data collected included birth weight, gestational age, ethnicity, race, type of pump used, and volume of enteral intake. The final analysis included 46 dyads, 45% Caucasian, 32% African American, and 39% Hispanic.
The researchers found that infants who experienced SSC at least once weekly ingested higher volumes of MOM than infants who did not have regular SSC. In addition, greater duration of SSC was associated with higher pumped milk volumes. This effect was seen in the 3rd and 4th week postpartum but not in the first and second week.
What else? See the question!
- For every minute of SSC there was an associated increase of 1.3-3.7 ml of expressed mother’s own milk per week.
- For every hour of SSC there was an associated increase of 5-6.5ml of expressed mother’s own milk per week.
- SSC for 1 hour every week was associated with an increase of 10 ml of expressed mother’s own milk per week.
See the Answer
Human milk diet, preferably mother's own milk (MOM) over donor milk (DM), is recommended for preterm infants. Expression of MOM in proximity to preterm infants, especially during or immediately after skin-to-skin contact (SSC), is associated with greater milk production. However, the correlation between SSC and MOM production during hospital admission in preterm infants has not yet been studied. Our study investigated the relationship between SSC and MOM production and consumption in preterm infants during the first postnatal month of life.
Materials and Methods
This was a prospective cohort study. Mothers and their preterm infants born at <35 weeks by gestational age (GA) and eligible for SSC within the first 5 postnatal days were eligible for the study. Mothers were given a binder to document pumped breast milk volumes and SSC sessions. Pumped breast milk volumes, enteral feeding type and volume, and SSC duration and frequency were collected daily over the first 28 days of life, along with demographic, perinatal, and feeding data from electronic medical records (EMR).
Mean birth GA and weight were 30 ± 3 weeks and 1,443 ± 576 g, respectively. SSC duration was inversely correlated with GA and weight. The SSC duration was positively correlated with ingested MOM volume after correcting for birth GA. The SSC duration was predictive of increased volumes of pumped MOM.
Our findings suggest that SSC duration is associated with improved MOM production and consumption. SSC can be a useful tool to increase MOM exposure and improve long-term health outcomes in preterm infants.
The authors found that the greater the duration of SSC care, the higher the milk volume expressed, with every additional 1 minute of SSC being associated with 1.3-3.7 ml of expressed mother’s-own-milk (MOM). This translated to an increase of 2.6-7.5 oz of MOM each week with one 60-minute SSC session. The authors point out that given the high cost of pasteurized donor human milk (PDHM) at $3-5 US dollars/ounce, every hour of SSC care could save up to $37.5 USD each week compared to feeding with PDHM.
It is unclear why SSC is associated with higher milk volumes. Perhaps parents who provide SSC are more likely to pump more often, and it is possible that having fewer barriers to SSC may be associated with more opportunity to pump frequently. There may be hormonal factors as well, such as higher prolactin and oxytocin levels, lower cortisol level, and less depression and anxiety.
The authors identified several barriers to SSC in the NICU, including not having enough trained staff to assist with SSC, variability in determining which infants are stable enough, staff motivation, challenges to parent visitation, and language barriers. This was a small study that didn’t see an impact of SSC on milk volume in the first 2 weeks postpartum. It does not appear that the study controlled for pumping frequency, which is one of the most important factors in determining volume of MOM for lactating parents in the NICU.
This study was a great start in investigating the relationship between SSC and MOM volume. Larger studies that control for the definition and frequency of pumping, as well as the frequency of SSC by the lactating parent vs other caregivers would add to the quality of this research.