Effect of cesarean section on the risk of autism spectrum disorders/attention deficit hyperactivity disorder in offspring: a meta-analysis

PURPOSE

This study was conducted to investigate the relationship between cesarean section (CS) offspring and autism spectrum disorders (ASD)/attention deficit hyperactivity disorder (ADHD).

METHODS

Searching of the databases (PubMed, Web of Science, Embase, and Cochrane Library) for studies on the relationship between mode of delivery and ASD/ADHD until August 2022. The primary outcome was the incidence of ASD/ADHD in the offspring.

RESULTS

This meta-analysis included 35 studies (12 cohort studies and 23 case-control studies). Statistical results showed a higher risk of ASD (odds ratio (OR) = 1.25, P < 0.001) and ADHD (OR = 1.11, P < 0.001) in CS offspring compared to the VD group. Partial subgroup analysis showed no difference in ASD risk between CS and VD offspring in sibling-matched groups (OR = 0.98, P = 0.625). The risk of ASD was higher in females (OR = 1.66, P = 0.003) than in males (OR = 1.17, P = 0.004) in the CS offspring compared with the VD group. There was no difference in the risk of ASD between CS under regional anesthesia group and VD group (OR = 1.07, P = 0.173). However, the risk of ASD was higher in the CS offspring under general anesthesia than in the VD offspring (OR = 1.62, P < 0.001). CS offspring developed autism (OR = 1.38, P = 0.011) and pervasive developmental disorder-not otherwise specified (OR = 1.46, P = 0.004) had a higher risk than VD offspring, but there was no difference in Asperger syndrome (OR = 1.19, P = 0.115). Offspring born via CS had a higher incidence of ADHD in different subgroup analyses (sibling-matched, type of CS, and study design).

CONCLUSIONS

In this meta-analysis, CS was a risk factor for ASD/ADHD in offspring compared with VD.

Cytokines and parturition: investigating adiponectin, TNF-α, and IL-6 in mother-newborn pairs

OBJECTIVE

Cytokines are reported to be associated with various pregnancy complications and health outcomes of the offspring. However, reference values during pregnancy have not been established, effects of clinical and obstetric factors have not been examined, and interactions between different cytokines have not yet been reported.

METHODS

In this cross-sectional study, we recruited 120 mother-newborn pairs. Maternal venous blood samples (6 mL) were taken on admission to the labor ward; newborn venous blood samples (6 mL) were drawn from the placental part of the umbilical cord (UC). Adiponectin, TNF-α, and IL-6 serum concentrations were measured by commercial immunoassays. Clinical and obstetric variables were analyzed for their association with maternal and UC cytokine concentrations.

RESULTS

Forty-six adiponectin pairs, 55 TNF-α pairs, and 14 IL-6 pairs were available for analysis. Correlation between UC and maternal adiponectin-, IL-6-, and TNF-α levels was low. We found a significant correlation of UC adiponectin with maternal brain-derived neurotrophic factor (BDNF) and maternal adiponectin, and between maternal leptin and maternal TNF-α.

CONCLUSIONS

Clinical and obstetric variables as well as interactions between cytokines may have an impact on serum concentrations of the respective cytokines in maternal and UC blood. Further studies are required to confirm our findings.

The Function of the Kynurenine Pathway in the Placenta: A Novel Pharmacotherapeutic Target?

(L-)tryptophan is metabolized via the kynurenine pathway into several kynurenine metabolites with distinct functions. Dysfunction of the kynurenine pathway can lead to impairments in vascular regulation, immune regulation, and tolerance. The first and rate limiting enzyme of this pathway, indoleamine 2,3-dioxygenase (IDO), is highly expressed in the placenta and reduced in placentas from complicated pregnancies. IDO is essential during pregnancy, as IDO inhibition in pregnant mice resulted in fetal loss. However, the exact function of placental IDO, as well as its exact placental localization, remain controversial. This review identified that two isoforms of IDO; IDO1 and IDO2, are differently expressed between placental cells, suggesting spatial segregation. Furthermore, this review summarizes how the placental kynurenine pathway is altered in pregnancy complications, including recurrent miscarriage, preterm birth, preeclampsia, and fetal growth restriction. Importantly, we describe that these alterations do not affect maternally circulating metabolite concentrations, suggesting that the kynurenine pathway functions as a local signaling pathway. In the placenta, it is an important source of de novo placental NAD⁺ synthesis and regulates fetal tryptophan and kynurenine metabolite supply. Therefore, kynurenine pathway interventions might provide opportunities to treat pregnancy complications, and this review discusses how such treatment could affect placental function and pregnancy development.

Caesarean section and offspring's emotional development: Sex differences and the role of key neurotransmitters

Increasing caesarean section (CS) rates are of global concern not only for health care providers but also from a more general public health point of view. Growing concern on the association between CS and offspring's neurodevelopmental outcomes have been raised in recent years, but the effect of CS on offspring's emotional development is rarely reported. By using mice models, we have set up two groups, ie. offspring born via CS and in-fostered by dams with vaginal delivery (VD), and offspring born via VD and in-fostered by their non-biological mothers. Depression-like behavioral was evaluated by sucrose preference test and forced swimming test, and anxiety-like behavioral was evaluated by open-field test and elevated plus maze test, respectively during offspring's adolescence and adulthood. Offspring's prefrontal cortex was collected for HE staining and assessment for DA, HVA, 5-HT, 5-HIAA. It was found that offspring born of CS have anxiety-like and depression-like behaviors in adolescence and adulthood. Male offspring was sensitive to be depressive and female offspring tended to be anxious. Although no significant sex difference was observed, there existed edema and nuclear retraction of neurons in the prefrontal cortex in offspring via CS during adolescence and adulthood. Compared with offspring born via VD, offspring through CS had shown higher DA and HVA levels while lower 5-HT and 5-HIAA levels in adolescence and adulthood, and this difference was observed in female offspring. The findings highlight the sex-specific effect of CS on offspring's emotional development. Variations in key neurotransmitters in the prefrontal cortex may partly explain the association between CS and offspring's emotional symptoms.

Ropivacaine at different concentrations on intrapartum fever, IL-6 and TNF-α in parturient with epidural labor analgesia

Effects of ropivacaine at different concentrations on intrapartum fever, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in parturient with epidural labor analgesia were compared to provide reference for the rational selection of anesthetics in clinic. Medical records of 198 cases of primi-paras admitted to the Obstetrics and Gynecology Department, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, from January 2017 to January 2018 were analyzed retrospectively and divided into 2 groups. A total of 105 patients were treated with 0.075% ropivacaine injection 10 ml and 0.5 µg/ml sulfentanyl injection 100 ml in parturition as the experimental group, and 93 patients were treated with 0.1% ropivacaine injection 10 ml and 0.5 µg/ml sulfentanyl injection 100 ml in parturition as the control group. After patient-controlled epidural analgesia, the pain visual analogue score (VAS), labor duration, administration time and febrile rate of parturient after administration were compared between the two groups at different time-points. Venous blood 2 ml was taken at T1 (cervix open to 2 cm), T2 (cervix fully open) and T3 (24 h postpartum), and the concentration of IL-6 TNF-α was detected by enzyme-linked immunosorbent assay. The time of the second stage of labor and analgesia were shorter in the experimental group than that in the control group after administration (P<0.05). The febrile rate of parturient in the experimental group was lower than that in the control group (P<0.05). The concentration of IL-6 and TNF-α in the experimental group was lower than that in the control group at T2 (P<0.05; P<0.01). The effect of patient-controlled epidural administration with 0.075% ropivacaine injection combined with 0.5 mg/ml sulfentanyl injection on labor analgesia is shorter than that with 0.1% ropivacaine combined with sulfentanyl. It could also shorten the duration of the second stage of labor, reduce the intrapartum febrile rate, and alleviate inflammation.

Maternal 25-hydroxyvitamin D is inversely correlated with foetal serotonin

OBJECTIVE

Maternal vitamin D deficiency during pregnancy has been linked to impaired neurocognitive development in childhood. The mechanism by which vitamin D affects childhood neurocognition is unclear but may be via interactions with serotonin, a neurotransmitter involved in foetal brain development. In this study, we aimed to explore associations between maternal and foetal vitamin D concentrations, and foetal serotonin concentrations at term.

STUDY DESIGN AND MEASUREMENTS

Serum 25-hydroxyvitamin D (25(OH)D, nmol/l) and serotonin (5-HT, nmol/l) concentrations were measured in maternal and umbilical cord blood from mother-infant pairs (n = 64). Association between maternal 25(OH)D, cord 25(OH)D and cord serotonin was explored using linear regression, before and after adjusting for maternal serotonin levels. We also assessed the effects of siRNA knockdown of the vitamin D receptor (VDR) and administration of 10 nm 1,25-dihydroxyvitamin D₃ on serotonin secretion in human umbilical vein endothelial cells (HUVECs) in vitro.

RESULTS

We observed an inverse relationship between both maternal and cord 25(OH)D concentrations with cord serotonin concentrations. The treatment of HUVECs with 1,25-dihydroxyvitamin D₃ in vitro decreased the release of serotonin (193·9 ±14·8 nmol/l vs 458·9 ± 317·5 nmol/l, control, P < 0·05). Conversely, inactivation of VDR increased serotonin release in cultured HUVECs.

CONCLUSIONS

These observations provide the first evidence of an inverse relationship between maternal 25(OH)D and foetal serotonin concentrations. We propose that maternal vitamin D deficiency increases foetal serotonin concentrations and thereby contributes to longer-term neurocognitive impairment in infants and children.

Reference values for interleukin-6 and interleukin-8 in cord blood of healthy term neonates and their association with stress-related perinatal factors

BACKGROUND

Automated interleukin assays are promising diagnostic aids for early-onset neonatal sepsis, however, reference values for healthy term neonates are incompletely known. The goal of this study is to determine reference values for interleukin-6 (IL-6) and interleukin-8 (IL-8) in cord blood of healthy term neonates.

METHODS AND FINDINGS

Women were recruited from April 2012 to August 2012. IL-6 and IL-8 levels were measured using an automated immunometric assay (Immulite) in cord blood of 93 healthy term newborns, 60 of them were born via vaginal delivery and 33 by elective caesarean section (ECS). A mean value for IL-8 of 8.1 ± 3.0 pg/mL was found in cord blood of healthy term neonates, which apply to both vaginal delivery and ECS. Regarding IL-6, two values apply. For vaginal delivery, a median value of 3.3 pg/mL (range, <2 to 9.53 pg/mL) was found, while for ECS, a median value of <2 pg/mL (range, <2 to 48 pg/mL) applies.

CONCLUSIONS

We propose a reference value of <14.1 pg/mL for IL-8 (mean + 2SD), applying to vaginally delivered and ECS-delivered healthy term newborns. From a clinical point of view, we also propose one reference value for IL-6 to be applied to vaginally delivered and ECS-delivered healthy term newborns, which is <10.2 pg/mL (97.5th percentile total group). These values have to be validated in larger cohorts of neonates, inclusive of those with and without early-onset neonatal sepsis.