Exposure to synthetic oxytocin during delivery and its effect on psychomotor development

Associations between different types of delivery, empathy, aggression, impulsivity and school bullying in children attending public and private schools in Pereira (Colombia)

This study aimed to correlate exposure to oxytocin during childbirth with behavioral determinants in teenage students. The Barratt Questionnaire (BQ), the Buss and Perry Aggression Questionnaire (BPAQ) and the Bryant Empathy Index (BEI), respectively measured impulsivity, aggression and empathy; the results were correlated with the roles of school bullying through the Velásquez and Pineda scale. Mothers were asked about birth circumstances. A total of 401 students were included (mean age 12 ± 1 years, 53,9 % were male, 53,3 % were attending a public school). 41,9 % of students had exogenous oxytocin exposure, 40,1 % had physiological oxytocin exposure, and 18 % had no oxytocin exposure. Regarding bullying, 75,1 % of students were classified as observers, 14,2 % were classified as victims, 6 % were classified as intimidators and 4,7 % exhibited an indifferent role. The mean value of the BPAQ was 78 ± 19, for the BEI was 78 ± 10 and for the BQ was 60 ± 10; all values were considered high. There were no significant differences among the type of delivery, sex and bullying roles or the type of delivery, aggressiveness and impulsivity according to sex; however, males had significantly lower empathy scores. There was no significant association between the type of delivery and the risk of assuming a bullying role. A regression model showed a significant association between attending a private school and a lower risk of developing a victim or intimidator role. This study could contribute to a better understanding of the processes involved in behavioral and emotional outcomes after birth, which can help to design prevention strategies to address increasing mental health problems in youth. Furthermore, this study could help emphasize the importance of promoting physiological delivery and find evidence that helps the scientific community design new work to deepen the relationship between oxytocin and behavior.

Tranexamic acid versus oxytocin prophylaxis in reducing post-partum blood loss, in low-risk pregnant women: TRANOXY STUDY, a phase III randomized clinical trial

Background

To assess the equivalence of tranexamic acid (TRAN) versus synthetic oxytocin (OXY) in reducing post-partum blood loss, in full-term patients (37-42 weeks), at low risk of post-partum hemorrhage, with vaginal childbirth.

Methods

Phase III, randomized (1:1), open-label, longitudinal, multi-center, prospective clinical trial (Prot. n 63209, ClinicalTrials.gov Identifier: NCT02775773). From January 7, 2020, to June 30, 2023, a total of 256 women were enrolled at two general urban community hospitals in Italy, serving a multi-ethnic patient population with National Health Insurance. The primary outcome was to explore a potential equivalence between the two treatments (OXY and TRAN) in preventing total blood loss. Therefore, we randomized 231 women into two groups: Group A (OXY), 127 women who were administered 10UI intramuscularly within 5 min from childbirth; Group B (TRAN), 104 women to whom 1-g slow intravenous infusion was administered within 5 min from childbirth.

Findings

At the time of delivery, mean blood loss for OXY group versus TRAN group was 269.12 mL versus 263.88 mL, respectively, with equivalence between the two groups. Similarly, there was equivalence in total blood loss between the OXY and the TRAN group (397.66 mL versus 405.64 mL, respectively. No statistical differences between Hb levels at admission and discharge in the two groups were reported. No difference was found in terms of additional uterotonic and surgical therapies between the two groups of patients. Neither group showed thrombotic complications at check-up performed after 7 days or after a questionnaire regarding adverse effects, subjected after 40 days.

Interpretation

The study shows the equivalence of tranexamic acid versus synthetic oxytocin in post-partum blood loss prophylaxis in term patients at low risk of PPH with vaginal childbirth. The safety profiles of OXY and TRAN were similar.

Funding

None.

Intrapartum synthetic oxytocin, behavioral and emotional problems in children, and the role of postnatal depressive symptoms, postnatal anxiety and mother-to-infant bonding: A Dutch prospective cohort study

OBJECTIVE

To examine the association between intrapartum synthetic oxytocin and child behavioral and emotional problems and to assess if maternal depressive or anxious symptoms or mother-to-infant bonding play a mediating role in this association.

DESIGN

Prospective cohort study.

SETTING

Population-based Pregnancy Anxiety and Depression Study.

PARTICIPANTS

Pregnant women in their first trimester of pregnancy visiting a total of 109 primary and nine secondary obstetric care centers in the Netherlands between 2010 and 2014 were invited to participate. Follow-up measures used for the present study were collected from May 2010 to January 2019. Women with multiple gestations and with a preterm birth were excluded.

MEASUREMENTS

Intrapartum synthetic oxytocin exposure status was based on medical birth records and was defined as its administration (Yes/No), either for labour induction or augmentation. Child behavioral and emotional problems were measured with the Child Behavior Checklist at up to 60 months postpartum. Maternal depressive symptoms, anxiety and mother-to infant bonding were measured with the Edinburgh Postnatal Depression Scale, State Trait Anxiety Inventory and the Mother-to-Infant Bonding Scale from 6 months postpartum. We used multivariable linear regression models to estimate standardized beta coefficients and unique variance explained.

FINDINGS

1,528 women responded. In total 607 women received intrapartum synthetic oxytocin. Intrapartum synthetic oxytocin administration was not associated with child behavioral and emotional problems, mother-to-infant bonding nor with postnatal anxiety. Intrapartum synthetic oxytocin was however significantly but weakly associated with more postnatal depressive symptoms (β=0.17, 95%CI of 0.03 to 0.30) explaining 0.6% of unique variance. Maternal postnatal depressive symptoms, postnatal anxiety symptoms and suboptimal mother-to-infant bonding were positively associated with child behavioral and emotional problems.

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

We found no evidence that intrapartum synthetic oxytocin is associated with child behavioral and emotional problems, mother-to-infant bonding, or with postnatal anxiety symptoms. Because there was no association between intrapartum synthetic oxytocin and behavioral and emotional problems in children no mediation analysis was carried out. However, intrapartum synthetic oxytocin was positively but weakly associated with postnatal depressive symptoms. The clinical relevance of this finding is negligible in the general population, but unknown in a population with a high risk of depression.

Birth signalling hormones and the developmental consequences of caesarean delivery

Rates of delivery by caesarean section (CS) are increasing around the globe and, although several epidemiological associations have already been observed between CS and health outcomes in later life, more are sure to be discovered as this practice continues to gain popularity. The components of vaginal delivery that protect offspring from the negative consequences of CS delivery in later life are currently unknown, although much attention to date has focused on differences in microbial colonisation. Here, we present the case that differing hormonal experiences at birth may also contribute to the neurodevelopmental consequences of CS delivery. Levels of each of the 'birth signalling hormones' (oxytocin, arginine vasopressin, epinephrine, norepinephrine and the glucocorticoids) are lower following CS compared to vaginal delivery, and there is substantial evidence for each that manipulations in early life results in long-term neurodevelopmental consequences. We draw from the research traditions of neuroendocrinology and developmental psychobiology to suggest that the perinatal period is a sensitive period, during which hormones achieve organisational effects. Furthermore, there is much to be learned from research on developmental programming by early-life stress that may inform research on CS, as a result of shared neuroendocrine mechanisms at work. We compare and contrast the effects of early-life stress with those of CS delivery and propose new avenues of research based on the links between the two bodies of literature. The research conducted to date suggests that the differences in hormone signalling seen in CS neonates may produce long-term neurodevelopmental consequences.

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.

In utero exposure to transient ischemia-hypoxemia promotes long-term neurodevelopmental abnormalities in male rat offspring

The impact of transient ischemic-hypoxemic insults on the developing fetal brain is poorly understood despite evidence suggesting an association with neurodevelopmental disorders such as schizophrenia and autism. To address this, we designed an aberrant uterine hypercontractility paradigm with oxytocin to better assess the consequences of acute, but transient, placental ischemia-hypoxemia in term pregnant rats. Using MRI, we confirmed that oxytocin-induced aberrant uterine hypercontractility substantially compromised uteroplacental perfusion. This was supported by the observation of oxidative stress and increased lactate concentration in the fetal brain. Genes related to oxidative stress pathways were significantly upregulated in male, but not female, offspring 1 hour after oxytocin-induced placental ischemia-hypoxemia. Persistent upregulation of select mitochondrial electron transport chain complex proteins in the anterior cingulate cortex of adolescent male offspring suggested that this sex-specific effect was enduring. Functionally, offspring exposed to oxytocin-induced uterine hypercontractility showed male-specific abnormalities in social behavior with associated region-specific changes in gene expression and functional cortical connectivity. Our findings, therefore, indicate that even transient but severe placental ischemia-hypoxemia could be detrimental to the developing brain and point to a possible mitochondrial link between intrauterine asphyxia and neurodevelopmental disorders.

Type of delivery and reading, writing, and arithmetic learning in twin births

This study analyses, in children born in twin births, the relationship between reading, writing and arithmetic learning, on the one hand, and type of delivery, on the other, controlling for the effect of interaction and/or confusion of third variables (maternal age at delivery, gestational age, fetal position, birthweight, 1-min Apgar score). In the planned retrospective cohort design, the exposed cohort consisted of children born by caesarean section, and the non-exposed cohort was comprised of children born vaginally. One hundred and twenty-four children born of twin births were evaluated during their first year of primary school: K-BIT tests were used to measure intelligence; the Evalúa-1 battery was used to assess reading, writing, and arithmetic ability; and the children's clinical histories were analysed for obstetric and neonatal variables. After applying binary logistic regressions for each dependent variable, it was found that caesarean delivery in twin births appeared as a possible independent risk factor for specific learning disabilities (LDs) in reading, writing, and arithmetic. Based on these results, further research using larger samples and at more advanced ages is required in order to analyse the influence of obstetric and neonatal variables on the processes underlying specific LDs.

Type of Delivery, Neuropsychological Development and Intelligence in Twin Births

Based on a retrospective cohort design with 6-year-old children born in twin births, the relationship between verbal, non-verbal, global neuropsychological development, general intelligence and type of delivery has been studied. To this end, the possible effect of third gestational, obstetric and neonatal variables, such as maternal age at delivery, fetal presentation, gestational age, newborn weight and Apgar at minute one, was controlled. The exposed cohort includes children born by cesarean section, and the unexposed cohort is composed of children born vaginally with or without induction. A total of 124 children were evaluated in their 1st year of primary school using the Child Neuropsychological Maturity Questionnaire, Kaufman's Intelligence Test and the medical histories of the children collected after birth. By means of binary logistic regression analysis, it has been found that the type of delivery is presented as an independent risk factor for disorders in verbal, non-verbal and global development and for the general intellectual difficulties of children born of multiple births. These results suggest the need to analyze in future prospective studies with broader samples the relationship between different types of obstetric and perinatal variables of birth type and infant neuropsychological development and general intelligence, in order to prevent possible psychological alterations from birth.

Behavioral and epigenetic consequences of oxytocin treatment at birth

Oxytocin is used in approximately half of all births in the United States during labor induction and/or augmentation. However, the effects of maternal oxytocin administration on offspring development have not been fully characterized. Here, we used the socially monogamous prairie vole to examine the hypothesis that oxytocin exposure at birth can have long-term developmental consequences. Maternally administered oxytocin increased methylation of the oxytocin receptor (Oxtr) in the fetal brain. As adults, oxytocin-exposed voles were more gregarious, with increased alloparental caregiving toward pups and increased close social contact with other adults. Cross-fostering indicated that these effects were the result of direct action on the offspring, rather than indirect effects via postnatal changes in maternal behavior. Male oxytocin-exposed offspring had increased oxytocin receptor density and expression in the brain as adults. These results show that long-term effects of perinatal oxytocin may be mediated by an epigenetic mechanism.

Nutritional, Socioeconomic, and Delivery Characteristics Are Associated with Neurodevelopment in Tanzanian Children

OBJECTIVES

To evaluate the hypothesis that various maternal, socioeconomic, delivery, and infant nutritional characteristics are associated with early childhood development in young Tanzanian children.

STUDY DESIGN

We performed a prospective cohort study among 206 HIV-exposed, uninfected and 247 HIV-unexposed Tanzanian infants who had been enrolled in 2 separate micronutrient trials (NCT00197730 and NCT00421668). Trained nurses administered culturally modified Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III), to evaluate cognitive, motor, and language development at 15 months of age. This analysis explored predictors of BSID-III z-scores using multivariable linear regression.

RESULTS

Among maternal determinants, we found that low maternal height predicted all BSID-III domains in HIV-unexposed children; low maternal education predicted lower cognitive (standardized mean difference, -0.41; 95% CI, -0.74 to -0.08) and lower gross motor scores (standardized mean difference, -0.32; 95% CI, -0.61 to -0.04) in HIV-exposed children. Among delivery characteristics, facility delivery predicted higher cognitive scores (standardized mean difference, 1.36; 95% CI, 0.26-2.46); and oxytocin administration predicted lower fine motor scores (standardized mean difference, -0.48; 95% CI, -0.87 to -0.09) in HIV-exposed children. Higher length-for-age z-scores at 6 weeks of age predicted better cognitive (standardized mean difference, 0.15; 95% CI, 0.01-0.29) and expressive language scores (standardized mean difference, 0.16; 95% CI, 0.02-0.29) at 15 months in HIV-exposed infants.

CONCLUSIONS

This hypothesis-generating study found significant associations between nutritional status and health of the mother and child, and maternal educational attainment, with direct measures of early childhood development at 15 months of age. In addition, several aspects of delivery (facility birth and oxytocin administration) were associated with early childhood development. Future intervention trials should focus on modifiable maternal, infant, and obstetric factors to strengthen the evidence base concerning early childhood development.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00197730 and NCT00421668.

Labor augmentation during birth and later cognitive ability in young adulthood

PURPOSE

Synthetic oxytocin for labor augmentation during birth has been linked to negative neurodevelopment effects in children. We examined whether maternal labor augmentation was associated with lower cognitive ability in young adulthoods.

PATIENTS AND METHODS

We identified 330,107 individuals (96.6% were men), with noninduced labor and with a cognitive ability test score, the Børge Priens Prøve (BPP) score, from draft board examinations in 1995-2015 (mean age, 18.8 years). Information on maternal labor augmentation was ascertained from the Danish Medical Birth Register, and we calculated mean differences in the BPP score according to maternal labor augmentation. We repeated our analyses in a sub-sample of siblings to control for unmeasured familial confounding.

RESULTS

Maternal labor augmentation was not associated with any noticeable decline in cognitive ability. However, the difference in the mean BPP score for exposure to maternal labor augmentation varied according to maternal parity, as the mean difference in BPP scores increased with increasing parity, in nulliparous: mean difference=-0.14 (95% CI=-0.23 to -0.04); in maternal parity 4+: mean difference=-1.21 (95% CI=-2.905 to -0.37). The sibling analysis showed little influence of shared familial factors on the association.

CONCLUSION

The mean BPP was slightly lower among labor augmented compared to nonaugmented and with an increasing difference with increasing parity. However, the differences were small and could not be considered of any clinical relevance. Furthermore, the sibling analyses suggested little confounding by familial factors.