Labor dystocia and risk of histological chorioamnionitis and funisitis: a study from a single tertiary referral center

Changes in fetal baroreceptor sensitivity during intrauterine inflammation in preterm fetal sheep

OBJECTIVE

Baroreflex is a regulatory mechanism that slows the fetal heart rate. This study aimed to investigate the effects of lipopolysaccharide (LPS)-induced endotoxemia on fetal baroreceptor sensitivity in preterm fetal sheep.

METHODS

The changes in fetal baroreceptor sensitivity were measured in seven chronically instrumented preterm fetal sheep. Fetal baroreceptor sensitivity was measured in three phases: (A) control phase, defined as the 24 h before the first injection of LPS; (B) acute phase, defined as the 24 h between the first and second injections of LPS; and (C) fetal acidosis phase, defined as the time from the second LPS injection until intrauterine fetal death. Histological examinations of the fetal membrane and umbilical cord were also conducted.

RESULTS

Each fetus developed metabolic acidosis after the second injection of LPS. The fetuses died 24.7 (SD = 6.1) hours after the second injection of LPS. Both the umbilical cord and fetal membranes showed histological evidence of severe inflammation. In total, 163 fetal baroreceptor measurements were performed in this experiment (A, n = 77 times; B, n = 60 times; C, n = 26 times). Fetal baroreceptor sensitivity showed significant differences in all three phases (A: 2.7 [SD = 0.2]; B: 2.5 [SD = 0.2]; and C: 1.5 [SD = 0.2]). Post hoc tests showed that baroreceptor sensitivity in the acidosis phase had decreased significantly compared to that in the control and acute phases (p<.001 and p=.002, respectively).

CONCLUSIONS

Fetal baroreceptor sensitivity decreased during fetal acidosis induced by LPSs.

Maternal and peripartum risk factors for acute funisitis among term deliveries complicated by intraamniotic infection

BACKGROUND

Acute funisitis-the histologic diagnosis of inflammation within the umbilical cord-represents a fetal inflammatory response and has been associated with adverse neonatal outcomes. Little is known regarding the maternal and intrapartum risk factors associated with the development of acute funisitis among term deliveries complicated by intraamniotic infection.

OBJECTIVE

This study aimed to identify the maternal and intrapartum risk factors associated with developing acute funisitis among term deliveries complicated by intraamniotic infection.

STUDY DESIGN

After institutional review board approval, we conducted a retrospective cohort study of term deliveries affected by clinical intraamniotic infection at a single tertiary center between 2013 and 2017, with placental pathology consistent with histologic chorioamnionitis. The exclusion criteria included intrauterine fetal demise, missing delivery information or placental pathology, and documented congenital fetal abnormalities. Maternal sociodemographic, antepartum, and intrapartum factors were compared among patients with acute funisitis on pathology to those without acute funisitis using bivariate statistics. Regression models were developed to estimate the adjusted odds ratios.

RESULTS

Of 123 patients meeting the inclusion criteria, 75 (61%) had acute funisitis on placental pathology. Compared with placental specimens without acute funisitis, acute funisitis was observed more frequently among patients with maternal BMI ≥30 kg/m2 (58.7% vs 39.6%, P=.04) and labor courses with increased rupture of membrane duration (17.3 vs 9.6 hours, P=.001). Use of fetal scalp electrode was observed less frequently in acute funisitis (5.3% vs 16.7%, P=.04) than cases without acute funisitis. In regression models, maternal BMI ≥30 kg/m2 (adjusted odds ratio, 2.67; 95% confidence interval, 1.21-5.90) and rupture of membrane >18 hours (adjusted odds ratio, 2.48; 95% confidence interval, 1.07-5.75) were significantly associated with acute funisitis. Fetal scalp electrode use (adjusted odds ratio, 0.18; 95% confidence interval, 0.04-0.71) was negatively associated with acute funisitis.

CONCLUSION

In term deliveries with intraamniotic infection and histologic chorioamnionitis, maternal BMI ≥30 kg/m2, and rupture of membrane>18 hours were associated with acute funisitis on placental pathology. As insight into the clinical impact of acute funisitis grows, the ability to predict which pregnancies are at the greatest risk for its development may allow for a tailored approach to predicting neonatal risk for sepsis and related comorbidity.

Amniotic Sludge and Prematurity: Systematic Review and Meta-analysis

OBJECTIVE

 To perform a systematic review and meta-analysis of studies on maternal, fetal, and neonatal outcomes of women with singleton pregnancies, after spontaneous conception, and with the diagnosis of amniotic sludge before 37 weeks of gestational age.

DATA SOURCES

 We conducted a search on the PubMed, Cochrane, Bireme, and Theses databases until June 2022.

SELECTION OF STUDIES

 Using the keywords intra-amniotic sludge or fluid sludge or echogenic particles, we found 263 articles, 132 of which were duplicates, and 70 were discarded because they did not meet the inclusion criteria.

DATA COLLECTION

 The articles retrieved were analyzed by 2 reviewers; 61 were selected for full-text analysis, 18 were included for a qualitative analysis, and 14, for a quantitative analysis.

DATA SYNTHESIS

 Among the maternal outcomes analyzed, there was an increased risk of preterm labor (95% confidence interval [95%CI]: 1.45-2.03), premature rupture of ovular membranes (95%CI: 1.99-3.79), and clinical (95%CI: 1.41-6.19) and histological chorioamnionitis (95%CI: 1.75-3.12). Regarding the fetal outcomes, there was a significant increase in the risk of morbidity (95%CI: 1.80-3.17), mortality (95%CI: 1.14-18.57), admission to the Neonatal Intensive Care Unit (NICU; 95%CI: 1.17-1.95), and neonatal sepsis (95%CI: 2.29-7.55).

CONCLUSION

 The results of the present study indicate that the presence of amniotic sludge is a risk marker for preterm delivery. Despite the heterogeneity of the studies analyzed, even in patients with other risk factors for prematurity, such as short cervix and previous preterm delivery, the presence of amniotic sludge increases the risk of premature labor. Moreover, antibiotic therapy seems to be a treatment for amniotic sludge, and it may prolong pregnancy.

Intra-Amniotic Inflammation or Infection: Suspected and Confirmed Diagnosis of "Triple I" at Term

Chorioamnionitis (CA) at term of pregnancy can have an infectious and/or inflammatory origin and is associated with adverse outcomes. Triple I (intrauterine inflammation, infection, or both, TI) has been proposed to reduce the overdiagnosis of infection and neonatal overtreatment. The aim of this study is to identify clinical and histological variables that could predict adverse outcomes when TI is suspected and/or confirmed. This retrospective cohort study included 404 pregnancies (gestational age ≥ 37 weeks) that were divided into 5 all-inclusive and mutually exclusive groups. TI was defined according to the NICHD definition of 2015, and it could be confirmed (TI+) or not confirmed (TI-) via histological examination. Signs of infection/inflammation that did not conform to the definition of TI were classified as "clinical suspicion" and could be supported (CS+) or not supported (CS-) by histology. Cases of histological chorioamnionitis (HCA) without clinical manifestation represented a fifth group. Whole placental involvement (WPLI) was defined as a histological inflammation involving the maternal and fetal sides. There were 113 TI+, 30 TI-, 186 CS+, 35 CS-, and 40 isolated HCA cases. WPLI was diagnosed in 133 cases (39.2%). Composite neonatal outcome (CNO) occurred in 114 cases (28.2%) while composite maternal outcome (CMO) occurred in 192 cases (47.5%). Compared with CS+, TI+ was more predictive of CNO (p = 0.001), CMO (p < 0.001), and WPLI (p = 0.005). WPLI was related both to CNO (p < 0.001) and to CMO (p = 0.046). TI+ and WPLI showed similar sensitivity but different specificity in predicting CNO. At logistic regression, CNO was independently predicted by TI+ (OR 2.21; p = 0.001) and by WPLI (OR 2.23; p = 0.001). Compared with CS, TI is a better predictor of CNO and can be useful for the identification of newborns at risk.

Association of labour duration in spontaneous deliveries with low neonatal Apgar scores and foetal acidosis: the Japan Environment and Children's Study

This study evaluated the association between labour duration (LD) and incidence of low neonatal Apgar scores and foetal acidosis. Data of 37,682 women with full-term singleton spontaneous vaginal deliveries from the Japan Environment and Children's Study were analysed. Women were classified according to the median LD as nulliparous (< 10 or ≥ 10 h) or multiparous (< 5 or ≥ 5 h) and further into five subcategories: nulliparous (< 10.0, 10.0-12.9, 13.0-15.9, 16.0-18.9, and ≥ 19 h) and multiparous (< 5.0, 5.0-7.9, 8.0-10.9, 11.0-13.9, and ≥ 14.0 h). Multiple logistic regression models were used to determine odds ratios (ORs) for outcomes in women with over-median LD. Over-median LD exhibited no statistically significant association with low neonatal Apgar scores. The adjusted ORs for both umbilical artery (UmA-pH) < 7.2 and < 7.1 were increased in nulliparous women with over-median LD, whereas only the adjusted OR for UmA-pH < 7.2 was increased in multiparous women with over-median LD. Moreover, this association manifested as a plateau in nulliparous women with LD ≥ 13 h and without dose-dependent association in multiparous women.

Gestational weight gain as a risk factor for dystocia during first delivery: a multicenter retrospective cohort study in Japan

Background

Dystocia is a common obstetric complication among nulliparous women, which requires medical intervention and carries the risk of negative maternal and neonatal outcomes. Our aim was to examine the association between body mass index (BMI) and the occurrence of dystocia. We also identified cutoffs of gestational weight gain, based on pre-pregnancy BMI, associated with the risk of dystocia.

Methods

This was a multicenter, retrospective, cohort study conducted in two tertiary Maternal–Fetal medicine units in Fukushima, Japan. The study population included nullipara women who delivered at either of the two units between January 1, 2013, and December 31, 2020. Women (n = 2597) were categorized into six groups (G) based on their pre-pregnancy BMI: G1 (< 18.5 kg/m²), G2 (18.5 to < 20.0 kg/m²), G3 (20.0 to < 23.0 kg/m²), G4 (23.0 to < 25.0 kg/m²), G5 (25.0 to < 30.0 kg/m²), and G6 (≥ 30.0 kg/m²). Using G3 as a reference, multiple logistic regression analyses were performed to estimate the risk of dystocia for each BMI category. Receiver operating characteristic curve analyses were performed to determine the cutoff value of gestational weight gain for the risk of dystocia.

Results

The highest BMI category (G6) was an independent risk factor for dystocia (adjusted odds ratio, 3.0; 95% confidence interval, 1.5–5.8). The receiver operating characteristic curve analysis revealed no association between gestational weight gain and the occurrence of dystocia in G5 and G6 (P = 0.446 and P = 0.291, respectively). For G1 to G4, AUC and predictive cutoffs of gestational weight gain for dystocia were as follows: G1, AUC 0.64 and cutoff 11.5 kg (P < 0.05); G2, AUC 0.63 and cutoff 12.3 kg (P < 0.05); G3, AUC 0.67 and cutoff 14.3 kg (P < 0.01); and G4, AUC 0.63 and cutoff 11.5 kg (P < 0.05).

Conclusion

A pre-pregnancy BMI > 30.0 kg/m² was an independent risk factor for dystocia. For women with a pre-pregnancy BMI < 25.0 kg/m², the risk of dystocia increases as a function of gestational weight gain. These findings could inform personalized preconception care for women to optimize maternal and neonatal health.

Optimal gestational weight gain to reduce the risk of hypertension disorders of pregnancy among women with obesity: A single tertiary referral center study in Japan

AIM

To examine the effect of weight gain during pregnancy on hypertension disorders of pregnancy among women with a prepregnancy body mass index ≥30.0 kg/m² .

METHODS

This retrospective cohort study included 257 Japanese women (116 primipara; 141 multipara) with singleton pregnancies with a prepregnancy body mass index ≥ 30.0 kg/m² , who gave birth during 2013 to 2020 at Ohta Nishinouchi Hospital. Multiple logistic regression analyses were performed to identify the effect of gestational weight gain on early-onset (<34 weeks), late-onset (≥34 weeks), and overall hypertension disorders of pregnancy.

RESULTS

The prevalence of hypertension disorders of pregnancy in primiparas and multiparas was 28.4% and 11.3%, respectively. By multiple logistic regression analysis, gestational weight gain during pregnancy increased the risk of early-onset (adjusted odds ratio: 1.20, 95% confidence interval: 1.03-1.39, p < 0.05) and overall hypertension disorders of pregnancy (adjusted odds ratio: 1.12, 95% confidence interval: 1.03-1.22, p < 0.05) among primiparas. Based on receiver operating characteristic curve analyses for early-onset (area under the curve 0.67, 95% confidence interval: 0.56-0.78; p < 0.05) and overall hypertension disorders of pregnancy (area under the curve 0.76, 95% confidence interval: 0.61-0.91; p < 0.05) among primiparas, we determined the cut-off weight gain during pregnancy for early-onset and overall hypertension disorders of pregnancy as 3.85 kg, with sensitivity/specificity of 0.76/0.59 and 0.91/0.53, respectively.

CONCLUSION

We recommend that the optimal gestational weight gain for reducing HDP be under 3.85 kg. This information may facilitate personalized pre-conception counseling among women with obesity.