Pilot study demonstrates that salivary oxytocin can be measured unobtrusively in preterm infants

Release of Oxytocin and Cortisol Is Associated With Neurobehavioral Patterns in Premature Infants

OBJECTIVE

To examine relationships among salivary oxytocin and cortisol levels in parents and preterm infants and neurobehavioral functioning in preterm infants after skin-to-skin contact.

DESIGN

A secondary analysis of a randomized crossover study.

SETTING

NICU.

PARTICIPANTS

Twenty-eight stable premature infants and their mothers and fathers.

METHODS

Participating infants contributed 108 saliva samples that we collected 45 minutes after skin-to-skin contact and tested for oxytocin and cortisol. We randomized data collection by whether the infant was held first by the mother or by the father. We conducted linear regression to test if summary scores on the NICU Network Neurobehavioral Scale were associated with salivary oxytocin and cortisol levels.

RESULTS

We found a significant negative relationship between infant oxytocin levels and the Stress scores (b = -0.07, p < .01) and the Excitability scores (b = -1.12, p = .04) among infants held skin-to-skin with their mothers. We found a significant positive relationship between infant oxytocin levels and the Self-Regulatory scores (b = 0.38, p = .05) among infants held skin-to-skin with their mothers. We found a significant positive relationship between infant cortisol level and the Stress scores (b = 0.05, p = .04), Excitability scores (b = 1.06, p = 0.05), and Asymmetrical Reflexes scores (b = 1.21, p = .03) among infants held skin-to-skin with their mothers. We only found a negative significant relationship between infant cortisol levels and the Stress scores (b = -0.03, p = .04) among infants held skin-to-skin with their fathers.

CONCLUSION

We found that oxytocin is an important biomarker that may improve infant neurobehavioral functioning. The data showed a difference in oxytocin responses after skin-to-skin contact with mothers compared to fathers.

A Systematic Review of the Effects of Skin-to-Skin Contact on Biomarkers of Stress in Preterm Infants and Parents

BACKGROUND

Premature infants and their parents experience significant stress related to separation and lifesaving procedures. While evidence suggests that skin-to-skin contact (SSC) is a stress-reducing intervention for both neonates and parents, the mechanisms that underlie its efficacy are not well understood.

OBJECTIVE

Purpose of this systematic review is to summarize the current state of knowledge on changes in biomarkers (ie, oxytocin [OT], cortisol, hypoxanthine, xanthine, uric acid, and allantoin), associated with SSC in premature infants and parents, that may reflect physiologic responses to stress.

METHODS

A comprehensive literature search was conducted from 1990 to 2020. Studies were selected using prespecified inclusion and exclusion criteria.

RESULTS

Of the 175 studies identified, only 19 are included in this review. Ten studies evaluated only infants, 2 evaluated only parents, and 7 evaluated for changes in biomarkers in both infants and parents. Cortisol was the most common biomarker evaluated. While changes in infants' cortisol levels were highly variable, in 55% of the parent studies, parent cortisol levels decreased following SSC. In both parents and infants, OT levels decreased following SSC. Only 1 study found that allantoin levels were significantly lower in infants who received SSC.

IMPLICATIONS FOR PRACTICE AND RESEARCH

While evidence suggests the numerous benefits of SSC, additional research is needed to identify the optimal biomarker to determine the mechanisms that underlie these effects. The use of novel biomarkers (eg, gene expression changes microbiome) may provide new insights into the mechanisms that underlie the efficacy of SSC.Video Abstract available at:https://journals.lww.com/advancesinneonatalcare/Pages/videogallery.aspx?autoPlay=false&videoId=48.

Expanding Regulation Theory With Oxytocin: A Psychoneurobiological Model for Infant Development

BACKGROUND

Oxytocin (OT), an affiliation hormone released during supportive social interactions, provides an exemplar of how social environments are reflected in our neurobiology from the beginning of life. A growing body of OT research has uncovered previously unknown functions of OT, including modulation of parenting behaviors, neuroprotection, affiliation, and bonding. Regulation theory provides a strong framework for describing how the maternal care environment affects infant neurodevelopment through a symphony of molecules that form the neurobiological milieu of the developing infant brain.

OBJECTIVES

The purpose of this article was to expand on regulation theory by discussing how OT-based processes contribute to infant neurobiology and by proposing a new model for maternal-infant nursing practice and research.

APPROACH

We structure our discussion of the socially based, neurobiological processes of OT through its effects in the nested hierarchies of genetic, epigenetic, molecular, cellular, neural circuit, multiorgan, and behavioral levels. Our discussion is also presented chronologically, as OT works through a positive feedback loop during infant neurodevelopment, beginning prenatally and continuing after birth.

IMPLICATIONS

Nurses are in a unique position to use innovative discoveries made by the biologic sciences to generate new nursing theories that inform clinical practice and inspire the development of innovative interventions that maximize the infant's exposure to supportive maternal care.

Viewpoints of Parents and Nurses on How to Design Products to Enhance Parent-Infant Bonding at Neonatal Intensive Care Units: A Qualitative Study Based on Existing Designs

AIM

To investigate how product design can be used to improve parent-infant bonding in a neonatal intensive care unit.

BACKGROUND

Impaired parent-infant bonding is an inevitable consequence of premature birth, which negatively influences development. Products, systems, or services that support the bonding process might counter these negative influences.

METHOD

The first step was to trace existing products by performing a literature search in PubMed, the university library, and Google. The identified existing designs were then used in semistructured interviews with nurses and parents to get insights into their desires and recommendations for product design to enhance bonding. Interviews contained open questions and a multiple-choice questionnaire based on the literature search.

RESULTS

In total, 17 existing design types were used in interviews with 11 parents and 23 nurses. All nurses explicitly stated that practicality was the first criterion designs aimed at enhancing bonding definitely had to meet. All parents indicated that they would like to use a design to enhance bonding if that would contribute to their child's health and development. For both parents and nurses, the most valuable way to enhance bonding seemed to be products to improve Kangaroo care; however, their specific desires varied substantially. Therefore, seven recurring themes were defined, resulting in nine general recommendations and six opportunities intended to enhance parent-infant bonding.

CONCLUSION

This study provides design recommendations and opportunities based on parents' and nurses' expert opinions. Designing to enhance bonding is considered valuable; however, designs should match the stakeholders' desires and conditions.

Plasma and Urinary Oxytocin Trajectories in Extremely Premature Infants During NICU Hospitalization

Extremely premature infants are at great risk for poor neurodevelopmental outcomes, in part because neurologic structures designed to mature in the womb must now do so in the extrauterine environment. Reliable biomarkers of neurodevelopment are especially critical in this population, as behavioral measures can be unreliable due to immaturity of the premature infant nervous system. Oxytocin (OT) has the potential to be a marker of neurobiological processes that offer infant neuroprotection. However, no studies have measured OT in the plasma and urine of premature infants. The purposes of this study were to describe plasma and urine OT levels of premature infants through 34 weeks corrected gestational age (CGA), determine whether plasma and urine OT are correlated, and explore associations between infant demographics and OT trajectories. Plasma and urine from 37 premature infants, born at gestational ages 25-28 6/7 weeks, were longitudinally collected at 14 days of life, then weekly until 34 weeks CGA. Plasma OT decreased with age, at a rate of 15% per week, and exhibited strong stability within infants. Urine OT was not correlated with plasma OT and did not show a significant trend over time; thus, urine may not be a reliable, noninvasive measurement in this population. Apgar score was the only infant demographic characteristic associated with plasma OT. Given the novelty of this work, replication is needed to confirm these findings, and future research should explore potential mechanisms (e.g., stress, normal maturation, and social experiences) that contribute to declining plasma OT levels in premature infants.