Breastfeeding Outcomes After Oxytocin Use During Childbirth: An Integrative Review

Cumulative oxytocin dose in spontaneous labour - Adverse postpartum outcomes, childbirth experience, and breastfeeding

OBJECTIVES

This study aimed to determine the association between the total cumulative oxytocin dose during labour and adverse postpartum outcomes, childbirth experience and breastfeeding in term primiparous women with spontaneous onset of labour.

STUDY DESIGN

A prospective observational multicentre study, including 1395 women with spontaneous labour, in seven hospitals in Southeast Sweden. Multivariable logistic regression (Crude Odds Ratios (OR) and adjusted OR (aOR) for relevant confounders) was used to analyze the association between oxytocin dose and postpartum outcomes. The exposure was the cumulative oxytocin dose during labour, classified in percentiles (<25th, 25-75th, >75th). The outcomes were occurrence of obstetric anal sphincter injury, postpartum haemorrhage (blood loss > 1000 ml), Apgar score < 7 at five minutes, umbilical cord arterial pH, postpartum bladder overdistension, exclusive breastfeeding at one week and three months, and the woman's perceived birth experience.

RESULTS

Women receiving high amounts (>75th percentile, >4370 mU) of oxytocin infusion during labour had an increased risk of postpartum haemorrhage (OR 2.73 (1.78-4.19)), an overdistended bladder (OR 2.19 (1.11-4.31)), an infant with an Apgar score < 7 at five minutes (OR 2.89 (1.27-6.57)), a negative birth experience (OR 1.83 (1.25-2.69)), and a decreased chance of exclusive breastfeeding at one week (OR 0.63 (0.41-0.96)). After adjusting for confounders, all outcomes remained statistically significant except risk of low Apgar score and chance of exclusive breastfeeding.

CONCLUSION

In women with high cumulative oxytocin dose during labour prompt, and prophylactic administration of uterotonics after delivery of the placenta should be considered to reduce the risk of postpartum haemorrhage. The risk for bladder overdistension can be reduced by implementing routines for observation for signs of bladder filling in the early postpartum period, as well as routine use of bladder scans post micturition to assess for successful bladder emptying. As women's birth experience have a major impact on their future mental health, should be routinely assessed postpartum, and support should be offered to women with negative experiences.

Impact of intrapartum oxytocin administration on neonatal sucking behavior and breastfeeding

This study aimed to examine the effect of intrapartum oxytocin administration on neonatal sucking behavior and breastfeeding. A total of 64 pairs (29 in the group treated with intrapartum oxytocin and 35 in the control group) of normal infants within 24-48 h of birth and their mothers were recruited. Sucking ability was evaluated by measuring Non-Nutritive Sucking (NNS) for 5 min. Data on the rate of exclusive breastfeeding at 1 month postpartum were collected. In the adjusted multiple regression models, intrapartum oxytocin exposure was significantly associated with fewer total NNS bursts (95% confidence interval (CI), -7.02 to -0.22), longer pause times (95% CI, 1.33 to 10.21), and greater pause-time variability (95% CI, 3.63 to 63.92). Effects estimated using structural equation modeling revealed that intrapartum oxytocin exposure had a significant negative and direct effect on the practice of exclusive breastfeeding 1 month postpartum (β = -0.238, p = 0.047). However, no NNS-mediated indirect effects were observed. This report demonstrates that infants born to mothers who receive intrapartum oxytocin may have impaired sucking ability for at least the first 48 h after birth, and breastfeeding support should be provided.

A longitudinal study of the association of epidural anesthesia and low-dose synthetic oxytocin regimens with breast milk supply and breastfeeding rates

Breastfeeding is known to improve maternal and child health. However, epidural anesthesia (EDA) and synthetic oxytocin (synOT) are suggested to have negative effects on breastfeeding. In this study, we aimed to determine the effects of intrapartum synOT and EDA on breast milk supply, breastfeeding rates, and maternal salivary oxytocin levels. Women were recruited during pregnancy or after birth at a single hospital. Data were collected at 3 days postpartum (T1), 1 month postpartum (T2), and 4 months postpartum (T3) on 83 low-risk primiparous women who planned to breastfeed for at least 12 weeks postpartum to avoid dropouts from early discontinuance of breastfeeding. Women with cesarean section, twin pregnancy, premature neonates, and an Apgar score of < 7 at 5 min were excluded. Participants recorded their 24-h milk supply by test weights at 3 days and 1 month postpartum. Additionally, they filled out questionnaires assessing their breastfeeding level and lactogenesis stage II initiation. Salivary oxytocin levels were obtained at 3 days postpartum. Women who delivered using EDA had lower salivary oxytocin levels (P = .055, d = .442), breast milk supply in early postpartum (P = .025, d = .520) and at 1 month postpartum (P = .036, d = .483), and breastfeeding rates at 4 months postpartum (P = .037, V = .236) than women who did not deliver using EDA. There was no association between breastfeeding and the use of intrapartum synOT. In conclusion, this study showed that women who delivered using EDA had lower breast milk supply in the early postpartum period and breastfeeding rates at 4 months postpartum. It also revealed that using synOT at low doses during labor did not affect breastfeeding. Thus, women who deliver using EDA need support for increased breast milk supply in the early postpartum period.Trial registration: UMIN000037783 (Clinical Trials Registry of University Hospital Information Network).

A prolonged latent phase: An early career in oxytocin during birth

•The author, a nurse-midwife scientist, shares her path to the study of the causes and consequences of clinical oxytocin use.•This paper highlights mentors and key research that informed new thinking about the role of oxytocin during parturition.•Future directions for improving maternal care during childbirth are presented, including genetic and epigenetic perspectives.

Maternal and newborn plasma oxytocin levels in response to maternal synthetic oxytocin administration during labour, birth and postpartum - a systematic review with implications for the function of the oxytocinergic system

BACKGROUND

The reproductive hormone oxytocin facilitates labour, birth and postpartum adaptations for women and newborns. Synthetic oxytocin is commonly given to induce or augment labour and to decrease postpartum bleeding.

AIM

To systematically review studies measuring plasma oxytocin levels in women and newborns following maternal administration of synthetic oxytocin during labour, birth and/or postpartum and to consider possible impacts on endogenous oxytocin and related systems.

METHODS

Systematic searches of PubMed, CINAHL, PsycInfo and Scopus databases followed PRISMA guidelines, including all peer-reviewed studies in languages understood by the authors. Thirty-five publications met inclusion criteria, including 1373 women and 148 newborns. Studies varied substantially in design and methodology, so classical meta-analysis was not possible. Therefore, results were categorized, analysed and summarised in text and tables.

RESULTS

Infusions of synthetic oxytocin increased maternal plasma oxytocin levels dose-dependently; doubling the infusion rate approximately doubled oxytocin levels. Infusions below 10 milliunits per minute (mU/min) did not raise maternal oxytocin above the range observed in physiological labour. At high intrapartum infusion rates (up to 32 mU/min) maternal plasma oxytocin reached 2-3 times physiological levels. Postpartum synthetic oxytocin regimens used comparatively higher doses with shorter duration compared to labour, giving greater but transient maternal oxytocin elevations. Total postpartum dose was comparable to total intrapartum dose following vaginal birth, but post-caesarean dosages were higher. Newborn oxytocin levels were higher in the umbilical artery vs. umbilical vein, and both were higher than maternal plasma levels, implying substantial fetal oxytocin production in labour. Newborn oxytocin levels were not further elevated following maternal intrapartum synthetic oxytocin, suggesting that synthetic oxytocin at clinical doses does not cross from mother to fetus.

CONCLUSIONS

Synthetic oxytocin infusion during labour increased maternal plasma oxytocin levels 2-3-fold at the highest doses and was not associated with neonatal plasma oxytocin elevations. Therefore, direct effects from synthetic oxytocin transfer to maternal brain or fetus are unlikely. However, infusions of synthetic oxytocin in labour change uterine contraction patterns. This may influence uterine blood flow and maternal autonomic nervous system activity, potentially harming the fetus and increasing maternal pain and stress.

Peripartum effects of synthetic oxytocin: The good, the bad, and the unknown

The first clinical applications of oxytocin (OT) were in obstetrics as a hormone to start and speed up labor and to control postpartum hemorrhage. Discoveries in the 1960s and 1970s revealed that the effects of OT are not limited to its peripheral actions around birth and milk ejection. Indeed, OT also acts as a neuromodulator in the brain affecting fear memory, social attachment, and other forms of social behaviors. The peripheral and central effects of OT have been separately subject to extensive scrutiny. However, the effects of peripheral OT-particularly in the form of administration of synthetic OT (synOT) around birth-on the central nervous system are surprisingly understudied. Here, we provide a narrative review of the current evidence, suggest putative mechanisms of synOT action, and provide new directions and hypotheses for future studies to bridge the gaps between neuroscience, obstetrics, and psychiatry.

Impact of caesarean delivery on children's autism-like behaviours: the mediation of exclusive breastfeeding

Background

The rate of autism spectrum disorder (ASD) has been rising worldwide, and therefore it is important to identify potential causes of ASD to facilitate early prevention. This study examined the role of breastfeeding and the association between caesarean delivery (CD) and children’s autism spectrum disorder.

Methods

The data were from the Ma’anshan birth cohort (MABC) in China, that was set up between May 2013 and September 2014. Women within 14 gestational weeks were recruited. The delivery mode was extracted from medical notes and infant feeding was obtained from questionnaire surveys. Autism-like behaviour was assessed using the Checklist for Autism in Toddlers (CHAT-23) when children were 18 months old, and 3 years of age. At 5 years of age, autism-like behaviour was assessed using the Clancy Autism Behavior Scale behavior. Structural equation models tested the mediation effects of breastfeeding between CD and children’s autism spectrum disorder.

Results

In all, 1520 (48.89%) women gave birth via CD, and 406 (13.86%) children were identified with autism-like behaviours at 18 months. Compared with women giving birth via vaginal delivery, those giving birth via CD were more likely to experience a higher proportion of delayed initiation of breastfeeding (p < 0.01), and delayed onset of lactogenesis (p < 0.01). CD was associated with a lower proportion of exclusive breastfeeding at 4 months after delivery (p = 0.02). Autism-like behaviour was less likely amongst infants with exclusively breastfeeding at 4 months than amongst those not exclusively breastfeeding at 4 months (p < 0.01). SEM indicated that women who gave birth by CD were more likely to stop exclusive breastfeeding in the first 4 months (standard estimations = − 0.04, p = 0.02), and those children who were not exclusively breastfed at 4 months were more likely to have autism-like behaviours (standard estimations = − 0.05, p < 0.01). The associations persisted at 3 years, but not at 5 years.

Conclusions

Exclusive breastfeeding at 4 months of age mediated the association between caesarean delivery and children’s autism-like behaviours.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13006-022-00493-6.

Immunomodulatory Properties of Human Breast Milk: MicroRNA Contents and Potential Epigenetic Effects

Infants who are exclusively breastfed in the first six months of age receive adequate nutrients, achieving optimal immune protection and growth. In addition to the known nutritional components of human breast milk (HBM), i.e., water, carbohydrates, fats and proteins, it is also a rich source of microRNAs, which impact epigenetic mechanisms. This comprehensive work presents an up-to-date overview of the immunomodulatory constituents of HBM, highlighting its content of circulating microRNAs. The epigenetic effects of HBM are discussed, especially those regulated by miRNAs. HBM contains more than 1400 microRNAs. The majority of these microRNAs originate from the lactating gland and are based on the remodeling of cells in the gland during breastfeeding. These miRNAs can affect epigenetic patterns by several mechanisms, including DNA methylation, histone modifications and RNA regulation, which could ultimately result in alterations in gene expressions. Therefore, the unique microRNA profile of HBM, including exosomal microRNAs, is implicated in the regulation of the genes responsible for a variety of immunological and physiological functions, such as FTO, INS, IGF1, NRF2, GLUT1 and FOXP3 genes. Hence, studying the HBM miRNA composition is important for improving the nutritional approaches for pregnancy and infant's early life and preventing diseases that could occur in the future. Interestingly, the composition of miRNAs in HBM is affected by multiple factors, including diet, environmental and genetic factors.

Intranasal Oxytocin Modulates the Salience Network in Aging

Growing evidence supports a role of the neuropeptide oxytocin in promoting social cognition and prosocial behavior, possibly via modulation of the salience of social information. The effect of intranasal oxytocin administration on the salience network, however, is not well understood, including in the aging brain. To address this research gap, 42 young (22.52 ± 3.02 years; 24 in the oxytocin group) and 43 older (71.12 ± 5.25 years; 21 in the oxytocin group) participants were randomized to either self-administer intranasal oxytocin or placebo prior to resting-state functional imaging. The salience network was identified using independent component analysis (ICA). Independent t-tests showed that individuals in the oxytocin compared to the placebo group had lower within-network resting-state functional connectivity, both for left amygdala (MNI coordinates: x = −18, y = 0, z = −15; corrected p < 0.05) within a more ventral salience network and for right insula (MNI coordinates: x = 39, y = 6, z = −6; corrected p < 0.05) within a more dorsal salience network. Age moderation analysis furthermore demonstrated that the oxytocin-reduced functional connectivity between the ventral salience network and the left amygdala was only present in older participants. These findings suggest a modulatory role of exogenous oxytocin on resting-state functional connectivity within the salience network and support age-differential effects of acute intranasal oxytocin administration on this network.

Intrapartum nipple stimulation therapy for labor induction: a randomized controlled external pilot study of acceptability and feasibility

OBJECTIVE

Nipple stimulation is purported as a natural and inexpensive method for inducing labor, but its use is understudied. We aimed to assess whether conducting a large randomized controlled trial comparing intrapartum nipple stimulation therapy versus oxytocin infusion is feasible and acceptable to patients and obstetric care providers.

STUDY DESIGN

This single-center parallel-group randomized controlled external pilot study (NCT04756089) included women with gestations ≥36 weeks who were planned to receive exogenous oxytocin for their labor induction. Those <18 years old, non-English-speaking, or with fetuses at increased risk for neonatal intensive care were excluded. Stratified by parity, women were randomized 3:1 to intrapartum nipple stimulation therapy or immediate receipt of oxytocin. Women assigned to nipple stimulation therapy were asked to stimulate with an electric breast pump or by hand for periods of at least 30 minutes, with breaks as needed for up to 15 minutes at a time, for at least a cumulative two hours prior to considering initiation of oxytocin, and to complete intrapartum diaries. Labor characteristics and outcomes were examined. Validated questionnaires were used to assess the participants' pain level during the intervention, their sense of control during childbirth, and their breastfeeding success. Primary outcome measures were recruitment, adherence to study protocol and follow-up, and cross-over rates.

RESULTS

620 women underwent labor induction from 3/13/21-6/23/21. Of 557 potentially eligible women, 53 were approached by available research staff. 24 (45%) consented and enrolled: 18 randomized to nipple stimulation and 6 randomized to oxytocin. One woman assigned to nipple stimulation withdrew due to delay of clinical care and received oxytocin (cross-over rate of 1/24 (4%)), and one woman assigned to oxytocin did not receive it due to spontaneous labor progress. All other participants followed their assigned intervention. The 17 women who performed nipple stimulation stimulated for a median duration of 198 (IQR 125-291) minutes and required a median of 69 (IQR 21-80) minutes of stimulation prior to achieving at least three contractions in a 10-minute window, averaged over 30 minutes (a.k.a. "adequate" contractions) Among those assigned to nipple stimulation therapy, 15/17 (88%) later received oxytocin infusion prior to delivery. The median time from intervention start to delivery was 16.4 (IQR 0.6-28.2) and 20.6 (IQR 14.2-23.4) hours for women assigned to nipple stimulation therapy versus oxytocin infusion, respectively. 12 (50%) women completed their postpartum study questionnaires.

CONCLUSION

Random assignment to intrapartum nipple stimulation therapy versus oxytocin infusion for labor induction is feasible and acceptable to patients and obstetric care providers.

Trends and characteristics of women undergoing induction of labour in a tertiary hospital setting: A cross-sectional study

BACKGROUND

In many well-resourced countries, rising rates of intervention are being observed during pregnancy, labour and childbirth with induction of labour (IOL) fast becoming one of the most common. In Australia, the rate of induction of labour has increased by over 30% since 2007, and today one in three women have their labours induced. We do not however have a good understanding of the contribution of specific obstetric populations to this trend.

METHODS

We examine the contribution of specific obstetric populations to induction of labour over a six-year period at one tertiary maternity service, using the Nippita classification system. Average Annual Percentage Changes (AAPC) were calculated along with 95% confidence intervals and P values set at 0.05.

RESULTS

The overall rate of induction of labour increased from 21.3% in 2012 to 30.9% in 2017, representing an Average Annual Percent Change of 8.1, P<0.0001 (95% CI 7-9.6). The greatest AAPC was seen in group 5 (parous, no previous caesarean section, 39-40 weeks, single cephalic), followed by group 2 (nulliparous, 39-40 weeks, single cephalic) and 1 (nulliparous, 37-38 weeks, single cephalic).

CONCLUSIONS

The use of the Nippita classification system allowed for standardised comparison across timepoints, facilitating identification of the subpopulations driving changes in rates of induction of labour. Rates of induction of labour saw a year on year increase which in this maternity service, it is not being driven by post-dates pregnancies. Further work is required to understand the role of other potential contributors such as diabetes.

The Role of Oxytocin and the Effect of Stress During Childbirth: Neurobiological Basics and Implications for Mother and Child

The neuropeptide oxytocin acts as a hormone and a neuromodulator, influencing a multitude of human social behaviors, including reproduction. During childbirth and the postpartum period, it plays a key role in regulating and controlling processes that ensure a safe birth and the health of mother and child. Especially the onset of labor, the progress of labor and initial breastfeeding are mediated by oxytocin. In the maternal brain it controls the initiation of the mother-infant bond and the mother's emotional responses towards her child. In this review we summarize the current state of knowledge about the role of oxytocin during the different aspects and mechanisms of human childbirth, combining research from human and animal studies. Physiological and psychological stress during childbirth and lactation can have negative effects on the progress of labor, breastfeeding and bonding. We discuss how maternity caregivers can support the positive effects of oxytocin and minimize the effects of stress. Furthermore, we highlight aspects of the basic neurobiological principles and connections where further research is needed to improve our understanding of the regulation and the effects of oxytocin to support maternal and infant health.

Maternal Depressive Symptoms and Infant Feeding Practices at Hospital Discharge: Findings from the Born in Queensland Study

INTRODUCTION

This study aims to explore association between maternal depressive symptoms and infant feeding practice at hospital discharge.

METHODS

Data were obtained from a birth cohort study based in Australia that linked to health administrative records. Maternal demographic data, mental health status derived from the Edinburgh Postnatal Depression Scale (EPDS), feeding practices of livebirths of at least 400 g or gestation periods of at least 20 weeks recorded during July-December 2015 were included (n = 14,658). Logistic regression models were performed to test association between presence of depressive symptoms and exclusive breast or formula feeding within 24 h prior to hospital discharge while adjusting for covariates known to be associated with breastfeeding.

RESULTS

About 12% of women self-reported having depressive symptoms (EPDS score ≥ 10). Although only 7% of women (n = 1012) exclusively formula fed their babies, having depressive symptoms was associated with a 51% higher likelihood of exclusive formula feeding at hospital discharge. The association remains significant after adjustment for maternal age, gestational weeks, number of previous pregnancies, socioeconomic and partner status (p < 0.001) and all other covariates (p = 0.009).

CONCLUSIONS FOR PRACTICE

Having depressive symptoms was associated with increased likelihood of exclusive formula feeding. Routine measurement post-delivery and early management of maternal depressive symptoms may influence infant feeding practice and reduce prevalence of exclusive formula feeding at hospital discharge.

Maternal plasma levels of oxytocin during breastfeeding-A systematic review

Introduction

Oxytocin is a key hormone in breastfeeding. No recent review on plasma levels of oxytocin in response to breastfeeding is available.

Materials and methods

Systematic literature searches on breastfeeding induced oxytocin levels were conducted 2017 and 2019 in PubMed, Scopus, CINAHL, and PsycINFO. Data on oxytocin linked effects and effects of medical interventions were included if available.

Results

We found 29 articles that met the inclusion criteria. All studies had an exploratory design and included 601 women. Data were extracted from the articles and summarised in tables. Breastfeeding induced an immediate and short lasting (20 minutes) release of oxytocin. The release was pulsatile early postpartum (5 pulses/10 minutes) and coalesced into a more protracted rise as lactation proceeded. Oxytocin levels were higher in multiparous versus primiparous women. The number of oxytocin pulses during early breastfeeding was associated with greater milk yield and longer duration of lactation and was reduced by stress. Breastfeeding-induced oxytocin release was associated with elevated prolactin levels; lowered ACTH and cortisol (stress hormones) and somatostatin (a gastrointestinal hormone) levels; enhanced sociability; and reduced anxiety, suggesting that oxytocin induces physiological and psychological adaptations in the mother. Mechanical breast pumping, but not bottle-feeding was associated with oxytocin and prolactin release and decreased stress levels. Emergency caesarean section reduced oxytocin and prolactin release in response to breastfeeding and also maternal mental adaptations. Epidural analgesia reduced prolactin and mental adaptation, whereas infusions of synthetic oxytocin increased prolactin and mental adaptation. Oxytocin infusion also restored negative effects induced by caesarean section and epidural analgesia.

Conclusions

Oxytocin is released in response to breastfeeding to cause milk ejection, and to induce physiological changes to promote milk production and psychological adaptations to facilitate motherhood. Stress and medical interventions during birth may influence these effects and thereby adversely affect the initiation of breastfeeding.

Relationships Among Factors Related to Childbirth and Breastfeeding Outcomes in Primiparous Women

OBJECTIVES

To explore the relationships among potentially modifiable factors related to childbirth and effective breastfeeding initiation at approximately 36 hours after birth and duration and exclusivity at hospital discharge, 2 weeks, 2 months, and 6 months after birth in primiparous women and to explore whether modifiable and nonmodifiable secondary factors and covariates influenced the relationships among factors related to childbirth and these breastfeeding outcomes.

DESIGN

A prospective, longitudinal, cohort study.

SETTING

The postpartum units of two general hospitals in eastern Canada.

PARTICIPANTS

Ninety-seven mother-infant dyads.

METHODS

We recorded demographic, childbirth, obstetric history, and breastfeeding data through chart review. A breastfeeding observation was completed at approximately 36 hours after birth by unit nurses. Participants maintained breastfeeding logs in hospital and for 6 months after birth and completed three self-report questionnaires before discharge. We analyzed outcomes using backward stepwise linear and logistic regression.

RESULTS

One childbirth factor, labor induced with oxytocin, was negatively associated with effective initiation of breastfeeding, and none was related to breastfeeding duration and exclusivity at any time point. Maternal weight; professional support; and newborn's gestational age at birth, 5-minute Apgar score, weight loss, LATCH score, and active feeds (newborn actively suckled at the breast) were significantly associated with breastfeeding outcomes.

CONCLUSION

Induction of labor with oxytocin should be used judiciously; when used, nurses must be hypervigilant to assess the mother-infant dyad for breastfeeding issues and to intervene to prevent or remediate them.

Association Between Intrapartum Factors and the Time to Breastfeeding Initiation

Background/Objectives: Early breastfeeding initiation is strongly recommended. Reasons for delayed breastfeeding initiation often include intrapartum interventions such as induction of labor, opioid pain medication administration, epidural analgesia, and caesarean birth. The majority of existing studies examining the timeliness of breastfeeding initiation are from low- or middle-income countries. The objective of this study is to examine intrapartum interventions on the time to breastfeeding initiation in a cohort of mothers from a high-income country. Materials and Methods: A cohort of 1,277 new mothers was recruited within 24 hours after birth from 4 hospitals in Hong Kong from 2011 to 2012. Participants completed a self-administered questionnaire immediately after recruitment. The rates of intrapartum interventions and the time to the first breastfeed were collected from participants' hospital record. Results: Among participants, 575 (45.5%) initiated breastfeeding within 1 hour of birth and the median time to the first breastfeed was 1.5 hours. The use of opioid pain medication (adjusted hazard ratio [aHR]: 0.78, 95% confidence interval [CI]: 0.67-0.91), assisted vaginal birth (aHR: 0.74, 95% CI 0.56-0.97), and caesarean section (aHR: 0.30, 95% CI 0.25-0.36) were associated with delayed breastfeeding, whereas epidural analgesia and induction of labor had no effect on breastfeeding initiation. Natural birth (i.e., no intrapartum interventions) was also significantly associated with early breastfeeding initiation (aHR: 1.75, 95% CI 1.54-1.99). Conclusions: Breastfeeding initiation was delayed in participants who had a caesarean birth and who received opioid pain medication. These women may require additional support to initiate breastfeeding soon after birth.

Perspectives of Pitocin administration on behavioral outcomes in the pediatric population: recent insights and future implications

Oxytocin plays an important role in the regulation of parturition as this peptide hormone promotes uterine smooth muscle contractility in gravid women undergoing labor. Here, we review the impact of Pitocin administration on behavioral outcomes in the pediatric population. Pitocin is a synthetic preparation of oxytocin widely used in the obstetric practice for the management of labor and postpartum hemorrhage. We begin by tracing the neuroanatomy of oxytocin-containing cells from an evolutionary perspective and then summarize key findings on behavioral and neural activity reported from offspring dosed with Pitocin during vaginal delivery. Finally, we discuss future directions that are experimentally tractable for understanding the developmental consequences of Pitocin administration on a small but growing subset of children worldwide. Given that fetal past experiences can shape the future behavior of the adult, further work on oxytocin signaling pathways will provide valuable references and insights for early-brain development and state-dependent regulation of behavioral outcome.

Parental adiposity differentially associates with newborn body composition

BACKGROUND

Maternal obesity increases offspring's obesity risk. However, studies have not often considered maternal metabolic and exercise patterns as well as paternal adiposity as potential covariates.

OBJECTIVE

To assess the relationship between parental and newborn adiposity.

METHODS

Participants were mother-child pairs (n = 209) and mother-father-offspring triads (n = 136). Parental (during gestation) and offspring (2 weeks old) percent fat mass (FM) were obtained using air displacement plethysmography. Maternal race, age, resting energy expenditure (indirect calorimetry), physical activity (accelerometry), gestational weight gain (GWG), gestational age (GA), delivery mode, infant's sex and infant feeding method were incorporated in multiple linear regression analyses. The association between parental FM and offspring insulin-like growth factor 1 (IGF-1) was assessed at age 2 years.

RESULTS

Maternal adiposity was positively-associated with male (β = 0.11, P = .015) and female (β = 0.13, P = .008) infant FM, whereas paternal adiposity was negatively-associated with male newborn adiposity (β = -0.09, P = .014). Breastfeeding, female sex, GA and GWG positively associated with newborn adiposity. Vaginal and C-section delivery methods associated with greater adiposity than vaginal induced delivery method. Plasma IGF-1 of 2-year-old boys and girls positively associated with their respective fathers' and mothers' FM.

CONCLUSIONS

Maternal and paternal adiposity differentially associate with newborn adiposity. The mechanisms of this finding remain to be determined.

Chronic oxytocin administration as a tool for investigation and treatment: A cross-disciplinary systematic review

Oxytocin (OT) subserves various physiological, behavioral, and cognitive processes. This paired with the ability to administer OT with minimal and inconsistent side effects has spurred research to explore its therapeutic potential. Findings from single-dose studies indicate that OT administration may be beneficial, at least under certain circumstances. The state of the field, however, is less clear regarding effects from chronic OT administration, which more closely resembles long-term treatment. To address this gap, this review synthesizes existing findings on the use of chronic OT administration in animal and human work. In addition to detailing the effects of chronic OT administration across different functional domains, this review highlights factors that have contributed to mixed findings. Based on this review, a basic framework of interrelated regulatory functions sensitive to chronic OT administration is offered. The paper also identifies future research directions across different contexts, populations, and outcomes, specifically calling for more systematic and standardized research on chronic OT administration in humans to supplement and expand what is currently known from preclinical work.

Traumatic events: exploring associations with maternal depression, infant bonding, and oxytocin in Latina mothers

Background

Childhood and adulthood traumatic experiences negatively impact maternal-infant bonding and increase risk of postpartum depression (PPD). Lower oxytocin levels have also been associated with PPD and compromised mother-infant bonding. Despite advances in these areas of investigation, much of the research has not included Latinas, who are important because they have high rates of fertility, traumatic events, and PPD.

Methods

To address gaps identified in the literature, we explored associations between traumatic life events, PPD, and bonding subscale scores (e.g., Impaired Bonding, Rejection and Anger, Anxiety about Care) in a sample of 28 Latinas. We also examined associations between these factors and oxytocin (OT). Wilcoxon signed-rank tests were employed to examine differences in subscale scores over time. Kruskal–Wallis one-way analysis of variance was used to examine differences in bonding subscale scores and OT by maternal depression status and traumatic events. We also explored interaction effects of traumatic events and OT AUC on bonding subscale scores.

Results

Women with PPD at 8 weeks had significantly higher Rejection and Anger subscale scores (p = 0.054) than non-PPD women, where higher scores represent more compromised bonding. Significant differences in Rejection and Anger (p = 0.042) and Anxiety about Care (p = 0.005) by adulthood traumatic histories were observed at 8 weeks postpartum. There was also a significant difference in Anxiety about Care scores at 4 weeks postpartum (p = 0.024) and Impaired Bonding at 8 weeks postpartum (p = 0.041) by trauma events involving an infant. There was a significant interaction between OT and childhood sexual abuse on Impaired Bonding (p = 0.038).

Conclusion

We observed differential responses in bonding subscale scores by traumatic histories. Women who experienced a trauma involving an infant had higher compromised bonding scores, whereas those with adulthood traumatic histories, such as intimate partner violence, had lower scores. We also found an interaction between childhood trauma and oxytocin levels on bonding scores, suggesting a physiological response to early abuse that can have implications on mothers’ bonding perceptions. These preliminary results suggest the need for additional research on the long-term emotional and physiological effects of traumatic events occurring prior to parturition.