The physiology and pharmacology of oxytocin in labor and in the peripartum period

Characterization of functionally relevant G protein-coupled receptors in endometriotic epithelial cells

Endometriosis is a chronic inflammatory disease characterized by the invasion of endometrial cells outside the uterine cavity. Current treatments for the disease, whose typical symptoms are pain and infertility, are unsatisfactory, relying on the surgical removal of the lesions and hormonal therapies with high symptom relapse and collateral effects, respectively. The aim of the present study was to exploit the rationale for G protein-coupled receptors (GPCRs) as non-hormonal therapeutic targets for this disease. To this end, human endometriotic epithelial cells 12Z were employed to characterize GPCR-mediated increases in intracellular Ca2+ concentrations ([Ca2+]i) using fluo-4, and cell invasion was measured using Boyden chamber assays. The results showed that the GPCR ligands oxytocin, bradykinin, histamine, lysophosphatidic acid, and sphingosine 1-phosphate (S1P) efficiently increased [Ca2+]i and induced cell invasion in endometriotic cells. In contrast, neuropeptide S, previously identified as a pro-invasive mediator, did not increase [Ca2+]i in 12Z cells. Notably, pretreatment with pertussis toxin significantly reduced S1P-dependent [Ca2+]i increase and cell invasion, highlighting the involvement of Gi-mediated signaling. Employing specific agonists and/or antagonists of S1P receptor isoforms, we demonstrated that S1P1/S1P3/S1P5, but not S1P2/S1P4 mediated the [Ca2+]i increases in this cellular model. Moreover, activation of S1P1/S1P4/S1P5, but not S1P2/S1P3, efficiently stimulated cell invasion. Taken together, we identified several GPCRs that are functionally relevant in human endometriotic epithelial cells and may potentially serve as targets for non-hormonal therapy of endometriosis.

Cadmium Exposure Disrupts Uterine Energy Metabolism and Coagulation Homeostasis During Labor in Institute of Cancer Research Mice: Insights from Transcriptomic Analysis

Background: Cadmium (Cd) is a highly toxic heavy metal. There are very few studies about the effects of Cd on reproductive health and metabolism, and even fewer on metabolic disorders in the uterus of mice in labor. This study is the first to establish a model of Cd exposure in the uterus of laboring mice and investigate the underlying metabolic mechanisms through transcriptomic analysis. Methods: Pregnant mice received intraperitoneal injections of CdCl2 (1.5 mg/kg) on gestational days 12.5, 14.5, and 16.5 were set up as the experimental group (Cd group), and pregnant mice injected with saline were set up as the control group (CT group). A total of 738 differentially expressed genes (DEGs) were screened using DESeq2 software, including 326 upregulated genes and 412 downregulated genes. Results: Through enrichment databases including the KEGG, GO, Reactome, and PANTHER, we identified 76 metabolism-related DEGs and performed protein-protein interaction (PPI) network analysis. The PPI results were visualized using Cytoscape software and further analyzed, with 18 hub genes (maximum clique centrality score > 10) identified through the MCC algorithm of the Cytohubba plugin. The results showed that the highest-scoring hub genes included mt-Co2, mt-Co3, mt-Atp6, mt-Atp8, mt-Nd3, and mt-Nd4l, which are involved in mitochondrial energy metabolism. The remaining lower-scoring hub genes were primarily associated with coagulation processes. Pathway analysis revealed hub genes predominantly involved in oxidative phosphorylation, complement and coagulation cascades, the cGMP-PKG signaling pathway, and thermogenesis. Conclusion: This study successfully established a Cd exposure-induced uterine injury model, providing valuable references for human reproductive health research.

Association of the time interval between first and last birth with obesity in middle-aged postmenopausal Chinese women: a cross-sectional study in southern China

Background

Birth interval is acknowledged as a significant factor affecting the health of women and their children. This study aimed to investigate the relationship between the time interval from the first to the last birth and the prevalence of general obesity, abdominal obesity, or both, among middle-aged postmenopausal Chinese women.

Methods

This cross-sectional survey examined 4,799 Chinese postmenopausal women, aged 45-59 years, who had at least one live birth. General obesity was assessed using body mass index (BMI), while abdominal obesity was evaluated through waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), and waist circumference (WC). Multivariate linear and logistic regression models were employed to analyze the associations between the time interval from the first to the last birth and obesity.

Results

The values of all four obesity measures increased with a longer time interval between the first and last births (P for trend <0.001). After adjusting for potential confounding variables, women with an interval of 10 or more years between their first and last birth exhibited a prevalence of obesity that was 1.49 times (95% confidence interval [CI], 1.12-1.99) higher by BMI, 1.29 times (95% CI, 1.02-1.61) higher by WC, 1.23 times (95% CI, 1.04-1.69) higher by WHtR, and 1.50 times (95% CI, 1.01-2.12) higher by WHR when compared to those with a 0 to 1-year interval.

Conclusion

The time interval between the first and last birth was positively associated with an increased risk of obesity, particularly abdominal obesity, in middle-aged postmenopausal Chinese women. Therefore, healthcare providers should prioritize reproductive health issues among women, actively promote appropriate birth intervals, and advocate for evidence-based pregnancy planning for women of childbearing age. Moreover, these research findings offer valuable scientific insights for policymakers, enabling them to develop more targeted obesity prevention and management strategies specifically tailored to this demographic group.

High- vs low-dose oxytocin regimens for labor augmentation: a systematic review and meta-analysis

OBJECTIVE

This study aimed to assess whether high- vs low-dose oxytocin regimens for labor augmentation are associated with differential risk of low Apgar score, neonatal acidosis, and other adverse labor outcomes.

DATA SOURCES

We searched electronic databases (MEDLINE, Embase, the Cochrane Library, CINAHL, Scopus, ClinicalTrials.gov) from inception up to March 2024 using combinations of the following key words: "oxytocin," "oxytocin regimen," "oxytocin protocol," "oxytocin dosage," "active management," "high dose protocol," "low dose protocol," and "augmentation of labor."

STUDY ELIGIBILITY CRITERIA

We included quasi-randomized and randomized controlled trials comparing continuous oxytocin infusion with high-dose regimens (intervention group) vs low-dose regimens (control group) in nulliparous or multiparous patients undergoing labor augmentation. High-dose regimens were defined as a starting oxytocin dose of ≥4 mU/min, increasing in increments of 3 to 7 mU/min every 15 to 40 minutes. Low-dose regimens were defined as a starting oxytocin dose of <4 mU/min, increasing in increments of 1 to 2 mU/min every 15 to 40 minutes (PROSPERO CRD42024500197).

METHODS

The coprimary outcomes were incidence of Apgar score <7 at 5 minutes and umbilical arterial pH <7.00. The secondary outcomes included cesarean delivery and chorioamnionitis. We performed random-effects head-to-head meta-analyses to compare high-dose with low-dose strategies, and reported summary risk ratios with 95% confidence intervals.

RESULTS

Ten randomized and quasi-randomized controlled trials of 5508 pregnancies met the inclusion criteria and were included in this meta-analysis. There was no difference in risk for the coprimary outcomes of Apgar score <7 at 5 minutes (relative risk, 0.94; 95% confidence interval, 0.60-1.46) and umbilical arterial pH <7.00 (relative risk, 0.77; 95% confidence interval, 0.50-1.20). There was also no difference in risk for cesarean delivery (relative risk, 0.83; 95% confidence interval, 0.67-1.02). High-dose oxytocin regimens were associated with significantly lower risk of chorioamnionitis (relative risk, 0.70; 95% confidence interval, 0.57-0.84; number needed to treat=25) and higher risk of tachysystole (relative risk, 1.32; 95% confidence interval, 1.21-1.43; P<.001).

CONCLUSION

When used for labor augmentation, high-dose oxytocin regimens decreased the risk of chorioamnionitis compared with low-dose regimens without affecting the risk of low Apgar scores, neonatal acidosis, or cesarean delivery. El resumen está disponible en Español al final del artículo.

Rational approach to fetal heart rate monitoring and management during the second stage of labor

Second stage of labor is considered to be associated with an increased risk of intrapartum fetal hypoxic injury. This is due to a combination of several risk factors such as -the increased frequency, strength and duration of uterine contractions due to higher number and affinity of myometrial oxytocin receptors; -the Ferguson's reflex which leads to a reflex release of endogenous oxytocin in response of the distension of the cervix by descending fetal head in late stages of labor; maternal expulsive efforts with the Valsalva manoeuvre that may reduce maternal oxygenation, as well as reduce the venous return and maternal cardiac output due to increased intrathoracic pressure, winch may lead to reduced placental oxygenation; - and increased fetal intracranial pressure due to head compression leading to a potential decrease in fetal cerebral oxygenation. In addition, the umbilical cord often forms one or more loops around the fetal neck, which may get tightened as the head descends leading to an acute and intermittent cessation of fetal oxygenation. Operative interventions during the second stage of labor such as vacuum, forceps or emergency caesarean section may increase the risk of maternal and fetal trauma. Therefore, an accurate interpretation of the fetal heart rate changes by applying the knowledge of fetal pathophysiology is essential: to timely recognise the onset of fetal decompensation preventing intrapartum hypoxic-ischaemic brain injuries; to avoid erroneous monitoring of the maternal heart rate as fetal heart rate; and to abstain from unnecessary operative interventions due to misinterpretation of the significance of the observed fetal heart rate changes.

Conventional and new immunotherapies for immune system dysregulation in postpartum mood disorders: comparisons to immune system dysregulations in bipolar disorder, major depression, and postpartum autoimmune thyroid disease

INTRODUCTION

Postpartum mood disorders are heterogenous disorders and comprise postpartum psychosis and postpartum depression. Evidence is accumulating that systemic monocyte/macrophage activation, low-grade inflammation and (premature senescence related) T cell defects increase the risk for mood disorders outside pregnancy by affecting the function of microglia and T cells in the emotional brain (the cortico-limbic system) leading to inadequate mood regulation upon stress.

AREAS COVERED

The evidence in the literature that similar immune dysregulations are present in postpartum mood disorders.

RESULTS

The physiological postpartum period is characterized by a rapid T cell surge and a mild activation of the monocyte/macrophage system. Postpartum mood disorder patients show a diminished T cell surge (including that of T regulatory cells) and an increase in low grade inflammation, that is, an increased inflammatory state of monocytes/macrophages and higher levels of serum pro-inflammatory cytokines.

EXPERT OPINION

Anti-inflammatory agents (e.g. COX-2 inhibitors) and T cell boosting agents (e.g. low-dose IL-2 therapy) should be further investigated as treatment. The hypothesis should be investigated that postpartum mood disorders are active episodes (triggered by changes in the postpartum immuno-endocrine milieu) in ongoing, dynamically fluctuating aberrant neuro-immune-endocrine trajectories leading to mood disorders in women (inheritably) vulnerable to these disorders.

The Effect of Maternal Oxytocin Induction during Birth on Early Neonatal Pain and Stress: A Quasi-Experimental Study

OBJECTIVE

Oxytocin induction is a commonly used intervention during childbirth worldwide. This study aimed to compare the pain and stress levels of newborns born to mothers who administered synthetic oxytocin at birth with those who did not.

METHODS

This quasi-experimental study included 164 participants and their newborns who were delivered vaginally in a public hospital. The data were collected using an Information Form, a Neonatal Follow-Up Form, and the Assessment of Neonatal Pain and Stress Scale (ALPS-Neo).

RESULTS

In the study, there were no differences between the two groups in terms of the participants' and newborns' demographic characteristics (p > .05). During and after drying, before, during, and after the first injection, and before, during, and after blood glucose measurement, the mean ALPS-Neo scores were higher in the oxytocin induction group, with the difference being statistically significant (p < .001).

CONCLUSION

Although the data presented here are observational, the findings indicate that infants born to participants who underwent oxytocin induction exhibit more intense pain and stress responses. The pain-stress scores of newborns born to participants who underwent oxytocin induction were higher than those of newborns whose mothers did not receive oxytocin induction.

Association of oxytocin augmentation with postpartum hemorrhage: a systematic review and meta-analysis

OBJECTIVE

The current study aims to evaluate the correlation between oxytocin augmentation and postpartum hemorrhage.

METHOD

PubMed, Web of Science, and Scopus has been searched for studies assessing the correlation between oxytocin augmentation and postpartum hemorrhage up to January 24, 2024. The search strategy included relevant keywords related to PPH and oxytocin augmentation. The risk of bias assessment was conducted by two reviewers using the Newcastle-Ottawa Scale (NOS). To pool the effects sized of included studies odds ratios (OR) of interest outcome with their 95% confidence interval (CI) were used.

RESULTS

Eight studies were included in this meta-analysis. The pooled analysis of the included studies showed a statistically significant association between oxytocin augmentation and increased odds of PPH (pooled odds ratio [OR] = 1.27, 95% confidence interval [CI]: 1.05-1.53; I2 = 84.94%; p = 0.01). Publication bias was assessed using funnel plots, which appeared relatively asymmetrical, indicating significant publication bias. Galbraith plot and trim and fill plot were used for publication bias. Sensitivity analyses were performed by leave one out method.

CONCLUSION

This meta-analysis suggests that using oxytocin for labor augmentation is linked to a significant increase in the risk of PPH. It highlights the need for careful monitoring and consideration when using oxytocin, especially in low and middle-income countries where guidelines and supervision are crucial.

Contractile responses of engineered human μmyometrium to prostaglandins and inflammatory cytokines

Preterm labor is a prevalent public health problem and occurs when the myometrium, the smooth muscle layer of the uterus, begins contracting before the fetus reaches full term. Abnormal contractions of the myometrium also underlie painful menstrual cramps, known as dysmenorrhea. Both disorders have been associated with increased production of prostaglandins and cytokines, yet the functional impacts of inflammatory mediators on the contractility of human myometrium have not been fully established, in part due to a lack of effective model systems. To address this, we engineered human myometrial microtissues (μmyometrium) on compliant hydrogels designed for traction force microscopy. We then measured μmyometrium contractility in response to a panel of compounds with known contractile effects and inflammatory mediators. We observed that prostaglandin F2α, interleukin 6, and interleukin 8 induced contraction, while prostaglandin E1 and prostaglandin E2 induced relaxation. Our data suggest that inflammation may be a key factor modulating uterine contractility in conditions including, but not limited to, preterm labor or dysmenorrhea. More broadly, our μmyometrium model can be used to systematically identify the functional impact of many small molecules on human myometrium.

Oxytocin with calcium vs oxytocin for induction of labor in women with term premature rupture of membranes: a randomized controlled trial

BACKGROUND

Intravenous calcium administration has shown promise in enhancing uterine contractions and reducing blood loss during cesarean delivery, but this regimen has not been compared in vaginal labor induction.

OBJECTIVE

This study aimed to determine the efficacy of oxytocin combined with calcium vs oxytocin alone for inducing labor in women with term premature rupture of membranes.

STUDY DESIGN

This single-blind, randomized controlled trial was conducted between October 2022 and May 2023 at a tertiary university hospital. Patients diagnosed with premature rupture of membranes were randomly allocated into 2 groups. The intervention group received a bolus of 10 mL of calcium gluconate followed by a continuous infusion of oxytocin via a pump (n=210), whereas the control group received only oxytocin infusion (n=218). The primary outcome was successful vaginal deliveries within 24 hours after labor induction. The secondary outcomes included the interval from labor induction to delivery, vaginal delivery blood loss, and maternal and neonatal complications.

RESULTS

Baseline characteristics, including maternal age, body mass index, and Bishop score before labor induction, were comparable between the groups. The rate of vaginal delivery within 24 hours after labor induction was statistically higher in the intervention group (79.52% vs 70.64%; P=.04). The participants in the intervention group experienced a shortened interval between labor induction and delivery (10.48 vs 11.25 hours; P=.037) and demonstrated a higher success rate in labor induction assessed by the onset of the active phase (93.80% vs 87.61%; P=.04) without increasing the cesarean delivery rate. Reduced hemorrhage was observed in the intervention group (242.5 vs 255.0 mL; P=.0015), and the maternal and neonatal outcomes were comparable between the groups.

CONCLUSION

The coadministration of calcium and oxytocin in labor induction among pregnancies with premature rupture of membranes was more efficient and safer than the administration of oxytocin alone. Our research suggests that the combination therapy of calcium and oxytocin may offer significant advantages during the process of labor induction and result in better outcomes. VIDEO ABSTRACT.

Oxytocin in growth, reproduction, restoration and health

This article summarizes my scientific work and describes some personal experiences during this period. After my basal medical training (MD) (1971), I obtained a PhD in pharmacology (1976) and ended up as a professor of Physiology. My initial studies were within the field of gastroenterology. I showed that the gastrointestinal hormone gastrin, which stimulates HCL secretion in the stomach, was released in response to stimulation of the vagal nerve. Later I showed that the entire endocrine system of the gastrointestinal (GI) tract that promotes digestion and anabolic metabolism and growth was under vagal nerve control. I also showed that activation of the vagal nerve inhibits the function of the inhibitory substance somatostatin. 10 years later, after some big changes in my personal life, my research focus changed. I became interested in female physiology, particularly the role of oxytocin. In addition, I became aware of the situation of female scientists and started to work with questions regarding equality between women and men. I gathered a group of interested female medical students and midwives around me. We demonstrated that breastfeeding and touch (e.g., between mother and baby), via stimulation of sensory nerves in the skin, activated the endocrine system of the GI tract and, thereby, anabolic processes and growth. The effects were exerted via a vagal mechanism and involved activation of parvocellular oxytocinergic neurons from the paraventricular nucleus (PVN). We also showed that the gastrointestinal hormone cholecystokinin stimulated the release of oxytocin in a calorie-dependent way via an afferent vagal mechanism. In summary, there is a bidirectional, vagally mediated connection between the endocrine system of the GI tract and the oxytocin producing neurons in the supraoptic (SON) and paraventricular (PVN) nuclei of the hypothalamus.1. Oxytocinergic neurons from the PVN enhances the activity of the endocrine system of the GI tract and thereby growth and regeneration. The effect is exerted via efferent vagal fibers which inhibit the release of somatostatin. 2. Food in the duodenum triggers a release of cholecystokinin (CCK), which via a vagal afferent mechanism stimulates the release and function of oxytocin. This mechanism is not activated in the absence of food intake. Administration of oxytocin induces a multitude of actions, i.e., anxiolytic and sedative effects, increased pain threshold, lowering of cortisol and blood pressure and an increased activity of the endocrine system of the GI tract. Repeated administration of oxytocin may induce long-term effects and "secondary" mechanisms such as an increased activity of alpha-2- adrenoceptors are involved. Oxytocin released by suckling during breastfeeding or by touch during social interaction will induce a similar effect spectrum. Activation of the parvocellular neurons will stimulate some aspects of social behavior, induce calm and well-being, and decrease levels of fear, stress, and pain. In addition, vagal functions and the activity of the endocrine system of the GI tract will be stimulated. Together, these effects are consistent with the oxytocin-mediated calm and connection response and, in a long-term perspective, with the promotion of well-being and health. A second period of professional difficulties occurred in the late 1990s. I moved to the Swedish University of Agriculture, where I started to investigate the role of oxytocin in interactions between humans and pets, as this type of interaction had been shown to promote health. I continued to study the role of oxytocin in female reproduction, in particular, the role of oxytocin during labor and birth and in the peripartum period. In addition, I started to write books about different aspects of oxytocin. I also wanted to establish a role for oxytocin in the treatment of vaginal atrophy. Several clinical studies show that local intravaginal application of oxytocin in women with vaginal atrophy increases the regeneration of vaginal mucosal cells and function.

Oscillations in delayed positive feedback systems

Positive feedback loops exist in many biological circuits important for organismal function. In this work, we investigate how temporal delay affects the dynamics of two canonical positive feedback models. We consider models of a genetic toggle switch and a one-way switch with delay added to the feedback terms. We show that long-lasting transient oscillations exist in both models under general conditions and that the duration depends strongly on the magnitude of the delay and initial conditions. We then show the existence of long-lasting oscillations in specific biological examples: the Cdc2-Cyclin B/Wee1 system and a genetic regulatory network. Our results challenge fundamental assumptions underlying oscillatory behavior in biological systems. While generally delayed negative feedback systems are canonical in generating oscillations, we show that delayed positive feedback systems are a mechanism for generating oscillations as well.

Variations in the use of oxytocin for augmentation of labour in Sweden: a population-based cohort study

National Swedish data shows substantial variation in the use of oxytocin for augmentation of spontaneous labour between obstetric units. This study aimed to investigate if variations in the use of oxytocin augmentation are associated with maternal and infant characteristics or clinical factors. We used a cohort design including women allocated to Robson group 1 (nulliparous women, gestational week ≥ 37 + 0, with singleton births in cephalic presentation and spontaneous onset of labour) and 3 (parous women, gestational week ≥ 37 + 0, with singleton births in cephalic presentation, spontaneous onset of labour, and no previous caesarean birth). Crude and adjusted logistic regression models with marginal standardisation were used to estimate risk ratios (RR) and risk differences (RD) with 95% confidence intervals (CI) for oxytocin use by obstetric unit. An interaction analysis was performed to investigate the potential modifying effect of epidural. The use of oxytocin varied between 47 and 73% in Robson group 1, and 10% and 33% in Robson group 3. Compared to the remainder of Sweden, the risk of oxytocin augmentation ranged from 13% lower (RD - 13.0, 95% CI - 15.5 to - 10.6) to 14% higher (RD 14.0, 95% CI 12.3-15.8) in Robson group 1, and from 6% lower (RD - 5.6, 95% CI - 6.8 to - 4.5) to 18% higher (RD 17.9, 95% CI 16.5-19.4) in Robson group 3. The most notable differences in risk estimates were observed among women in Robson group 3 with epidural. In conclusion, variations in oxytocin use remained despite adjusting for risk factors. This indicates unjustified differences in use of oxytocin in clinical practice.

A qualitative exploration of the challenges providers experience during peripartum management of patients with a body mass index ≥ 50 kg/m2 and recommendations for improvement

BACKGROUND

The objective of this research was to conduct a qualitative study among a diverse group of providers to identify their clinical needs, barriers, and adverse safety events in the peripartum care of people with a body mass index (BMI) ≥ 50 kg/m2.

METHODS

Obstetricians, anesthesiologists, certified nurse midwives, nurse practitioners, and nurses were invited to participate in focus group discussions if they were employed at the hospital for >6 months. Key concepts in the focus group guide included: (1) Discussion of challenging situations, (2) Current peripartum management approaches, (3) Patient and family knowledge and counseling, (4) Design and implementation of a guideline (e.g., checklist or toolkit) for peripartum care. The audiotaped focus groups were transcribed verbatim, uploaded to a qualitative analysis software program, and analyzed using inductive and constant comparative approaches. Emerging themes were summarized along with representative quotes.

RESULTS

Five focus groups of 27 providers were completed in 2023. The themes included staffing (level of experience, nursing-patient ratios, safety concerns), equipment (limitations of transfer mats, need for larger sizes, location for blood pressure cuff, patient embarrassment), titrating oxytocin (lack of guidelines, range of uses), monitoring fetal heart rate and contractions, patient positioning, and communication (lack of patient feedback, need for bias training, need for interdisciplinary relationships). Providers gave examples of items to include in a "BMI cart" and suggestions for a guideline including designated rooms for patients with a BMI ≥ 50 kg/m2, defining nursing ratios and oxytocin titration plans, postpartum incentive spirometer, and touch points with providers (nursing, physicians) at every shift change.

CONCLUSIONS

Providers discussed a range of challenges and described how current approaches to care may negatively affect the peripartum experience and pose threats to safety for patients with a BMI ≥ 50 kg/m2 and their providers. We gathered information on improving equipment and communication among providers.

Sacred space: a qualitative interpretive meta-synthesis of women's experiences of supportive birthing environments

BACKGROUND

In the United States there are roughly three million births a year, ranging from cesarean to natural births. A major aspect of the birthing process is related to the healing environment, and how that helps or harms healing for the mother and child. Using the theoretical framework, Theory of Supportive Care Settings (TSCS), this study aimed to explore what is necessary to have a safe and sacred healing environment for mothers.

METHOD

This study utilized an updated Qualitative Interpretive Meta-synthesis (QIMS) design called QIMS-DTT [deductive theory testing] to answer the research question, What are mother's experiences of environmental factors contributing to a supportive birthing environment within healthcare settings?

RESULTS

Key terms were run through multiple databases, which resulted in 5,688 articles. After title and abstract screening, 43 were left for full-text, 12 were excluded, leaving 31 to be included in the final QIMS. Five main themes emerged from analysis: 1) Service in the environment, 2) Recognizing oneself within the birthing space, 3) Creating connections with support systems, 4) Being welcomed into the birthing space, and 5) Feeling safe within the birthing environment.

CONCLUSIONS

Providing a warm and welcoming birth space is crucial for people who give birth to have positive experiences. Providing spaces where the person can feel safe and supported allows them to find empowerment in the situation where they have limited control.

Effects of systemic oxytocin receptor activation and blockade on risky decision making in female and male rats

The neuropeptide oxytocin is traditionally known for its roles in parturition, lactation, and social behavior. Other data, however, show that oxytocin can modulate behaviors outside of these contexts, including drug self-administration and some aspects of cost-benefit decision making. Here we used a pharmacological approach to investigate the contributions of oxytocin signaling to decision making under risk of explicit punishment. Female and male Long-Evans rats were trained on a risky decision-making task in which they chose between a small, "safe" food reward and a large, "risky" food reward that was accompanied by varying probabilities of mild footshock. Once stable choice behavior emerged, rats were tested in the task following acute intraperitoneal injections of oxytocin or the oxytocin receptor antagonist L-368,899. Neither drug affected task performance in males. In females, however, both oxytocin and L-368,899 caused a dose-dependent reduction in preference for large risky reward. Control experiments showed that these effects could not be accounted for by alterations in food motivation or shock sensitivity. Together, these results reveal a sex-dependent effect of oxytocin signaling on risky decision making in rats.

Signaling mechanisms underlying activity-dependent integration of adult-born neurons in the mouse olfactory bulb

Adult neurogenesis has fascinated the field of neuroscience for decades given the prospects of harnessing mechanisms that facilitate the rewiring and/or replacement of adult brain tissue. The subgranular zone of the hippocampus and the subventricular zone of the lateral ventricle are the two main areas in the brain that exhibit ongoing neurogenesis. Of these, adult-born neurons within the olfactory bulb have proven to be a powerful model for studying circuit plasticity, providing a broad and accessible avenue into neuron development, migration, and continued circuit integration within adult brain tissue. This review focuses on some of the recognized molecular and signaling mechanisms underlying activity-dependent adult-born neuron development. Notably, olfactory activity and behavioral states contribute to adult-born neuron plasticity through sensory and centrifugal inputs, in which calcium-dependent transcriptional programs, local translation, and neuropeptide signaling play important roles. This review also highlights areas of needed continued investigation to better understand the remarkable phenomenon of adult-born neuron integration.

Parturition at term: induction, second and third stages of labor, and optimal management of life-threatening complications-hemorrhage, infection, and uterine rupture

Childbirth is a defining moment in anyone's life, and it occurs 140 million times per year. Largely a physiologic process, parturition does come with risks; one mother dies every two minutes. These deaths occur mostly among healthy women, and many are considered preventable. For each death, 20 to 30 mothers experience complications that compromise their short- and long-term health. The risk of birth extends to the newborn, and, in 2020, 2.4 million neonates died, 25% in the first day of life. Hence, intrapartum care is an important priority for society. The American Journal of Obstetrics & Gynecology has devoted two special Supplements in 2023 and 2024 to the clinical aspects of labor at term. This article describes the content of the Supplements and highlights new developments in the induction of labor (a comparison of methods, definition of failed induction, new pharmacologic agents), management of the second stage, the value of intrapartum sonography, new concepts on soft tissue dystocia, optimal care during the third stage, and common complications that account for maternal death, such as infection, hemorrhage, and uterine rupture. All articles are available to subscribers and non-subscribers and have supporting video content to enhance dissemination and improve intrapartum care. Our hope is that no mother suffers because of lack of information.

Calm Contact Technique Based on the Endocrinological Mechanism of Hypnosis-A Theoretical Proposal

This paper proposes the "calm contact" technique: an imaginative scenario where someone is in gentle contact with a loved one where the essence of the experience is to enjoy safety and calmness in peaceful social contact. The theoretical background is outlined by combining the brain mechanisms of stress reactions and hypnosis. In addition to the ancient stress responses (flight or fight or freeze), there are oxytocin-based options at the human level: tend and befriend behavior and the state of calm and connection, which is not a stress reaction but a resting reaction. These social-based reactions could prevent the organism from the primitive freezing response. Some studies proved that "hypnosis" as a setting reduces cortisol levels and could raise oxytocin levels. The beneficial mechanisms of the "calm contact" technique are analyzed in relation to "social support" and the psychoaffective effects of central oxytocin. The subjective effects of the proposed technique are outlined based on reports of healthy volunteers. The "calm contact" technique could be an alternative or adjunct to the "safe place" technique, applying the recent findings of endocrinological brain mechanisms of hypnosis. Clinical implications and limitations are briefly summarized.