A stochastic model for early placental development

In the human, placental structure is closely related to placental function and consequent pregnancy outcome. Studies have noted abnormal placental shape in small-for-gestational age infants which extends to increased lifetime risk of cardiovascular disease. The origins and determinants of placental shape are incompletely under-stood and are difficult to study in vivo. In this paper we model the early development of the placenta in the human, based on the hypothesis that this is driven by dynamics dominated by a chemo-attractant effect emanating from proximal spiral arteries in the decidua. We derive and explore a two-dimensional stochastic model for these events, and investigate the effects of loss of spiral arteries in regions near to the cord insertion on the shape of the placenta. This model demonstrates that placental shape is highly variable and disruption of spiral arteries can exert profound effects on placental shape, particularly if this disruption is close to the cord insertion. Thus, placental shape reflects the underlying maternal vascular bed. Abnormal placental shape may reflect an abnormal uterine environment, which predisposes to pregnancy complications

Stillbirth and intrauterine fetal death:role of routine histopathological placental findings to determine cause of death

OBJECTIVES: Placental abnormalities are a common cause of death in stillbirth, ranking second only to unexplained deaths, though there is wide variation in the proportion attributed to placental disease. In clinical practice, interpretation of the significance of placental findings is difficult, since many placental features in stillbirths overlap with those in live births. Our aim was to examine objectively classified placental findings from a series of > 1000 autopsies following intrauterine death in order to evaluate the role of placental histological examination in determining the cause of death. METHODS: As part of a larger study evaluating several aspects of autopsy findings in intrauterine death, a dedicated database was used to collate antenatal and postmortem examination details for all cases examined between 2005 and 2013 at two tertiary specialist centers in London, UK. Histological findings for placentas were evaluated in relation to the final cause of death. RESULTS: Among 1064 intrauterine deaths, 946 (89%) cases had the placenta submitted for examination as part of the autopsy. Of these, 307 (32%) cases had the cause of death assigned to abnormalities of the placenta, cord or membranes. Around one third of stillbirths (≥ 24 weeks) had some isolated placental histological abnormality identified, many of uncertain significance, a significantly greater proportion than in cases of second-trimester intrauterine fetal demise (P < 0.0001). The cause of death was ascending infection in 176/946 (19%) cases, peaking at 22 weeks' gestation, with significantly more black mothers having ascending infection compared with other ethnicities (P < 0.0001). Maternal vascular malperfusion was the largest category of placental abnormalities in stillbirth, with peak prevalence in the early third trimester. There were 18 (2%) cases with specific histological abnormalities, including chronic histiocytic intervillositis and massive perivillous fibrin deposition. CONCLUSIONS: Placental pathologies represent the largest category of cause of intrauterine death. Placental histological examination is the single most useful component of the autopsy process in this clinical setting. A minority of cases are associated with specific placental pathologies, often with high recurrence rates, that can be diagnosed only on microscopic examination of the placenta. Many deaths remain unexplained, although placental histological lesions may be present which are of uncertain significance. A rigorous, systematic approach to placental pathology research and classification may yield better understanding of the significance of placental findings and reduce the rate of unexplained intrauterine deaths

Stillbirth is associated with perceived alterations in fetal activity - findings from an international case control study

Background Stillbirth after 28 weeks gestation affects between 1.3–8.8 per 1000 births in high-income countries. The majority of stillbirths in this setting occur in women without established risk factors. Identification of risk factors which could be identified and managed in pregnancy is a priority in stillbirth prevention research. This study aimed to evaluate women’s experiences of fetal movements and how these relate to stillbirth. Methods An international internet-based case–control study of women who had a stillbirth ≥28 weeks’ gestation within 30 days prior to completing the survey (n = 153) and women with an ongoing pregnancy or a live born child (n = 480). The online questionnaire was developed with parent stakeholder organizations using a mixture of categorical and open–ended responses and Likert scales. Univariate and multiple logistic regression was used to determine crude (unadjusted) and adjusted odds ratios (aOR) with 95% confidence intervals (CI). Summative content analysis was used to analyse free text responses. Results Women whose pregnancy ended in stillbirth were less likely to check fetal movements (aOR 0.54, 95% CI 0.35–0.83) and were less likely to be told to do so by a health professional (aOR 0.55, 95% CI 0.36–0.86). Pregnancies ending in stillbirth were more frequently associated with significant abnormalities in fetal movements in the preceding two weeks; this included a significant reduction in fetal activity (aOR 14.1, 95% CI 7.27–27.45) or sudden single episode of excessive fetal activity (aOR 4.30, 95% CI 2.25–8.24). Cases described their perception of changes in fetal activity differently to healthy controls e.g. vigorous activity was described as “frantic”, “wild” or “crazy” compared to “powerful” or “strong”. Conclusions Alterations in fetal activity are associated with increased risk of stillbirth. Pregnant women should be educated about awareness of fetal activity and reporting abnormal activity to health professionals

Immunomodulatory Therapy Reduces the Severity of Placental Lesions in Chronic Histiocytic Intervillositis

From Frontiers via Jisc Publications RouterHistory: collection 2021, received 2021-08-04, accepted 2021-09-23, epub 2021-10-18Publication status: PublishedChronic histiocytic intervillositis (CHI) is a rare, but highly recurrent inflammatory placental lesion wherein maternal macrophages infiltrate the intervillous space. Pregnancies with CHI are at high risk of fetal growth restriction, miscarriage or stillbirth. Presently, the diagnosis can only be made after histopathological examination of the placenta. Given its proposed immunological etiology, current treatments include aspirin, heparin, and immunomodulatory agents. However, the rationale for these medications is largely based upon small case series and reports as there is a lack of larger studies investigating treatment efficacy. Therefore, this study sought to determine whether inclusion of immunomodulatory medications was effective at reducing the severity of lesions and improving pregnancy outcomes in subsequent pregnancies. Thirty-three women with a history of CHI in at least one pregnancy (index case) were identified retrospectively through medical records. Twenty-eight participants presented with a first subsequent pregnancy and a further 11 with a second subsequent pregnancy at a specialist clinic for pregnancy after loss. Data on maternal demographics, medical history, medication, pregnancy outcome, and placental pathology was collected and compared between pregnancies. Twenty-seven (69%) subsequent pregnancies were treated with at least one or both of prednisolone and hydroxychloroquine. Inclusion of at least one immunomodulatory agent in treatment regimen resulted in an almost 25% increase in overall livebirth rate (61.5 vs. 86.2%). In women treated with immunomodulatory medication a greater proportion of placentas had reduced severity of lesions compared to those treated without (86.7 vs. 33.3%, respectively). A reduction in CHI severity was associated with a 62.3% improvement in livebirth rate compared to those where severity remained unchanged in relation to the index case. These data provide preliminary evidence that the use of immunomodulatory medication in the management of CHI improves histopathological lesions and the chance of livebirth in subsequent pregnancies. Due to CHI's rarity and ethical and feasibility issues, randomized controlled trials in affected women are challenging to conduct. As a result, collaboration between centers is required in future to increase study sample sizes and elucidate the mechanisms of hydroxychloroquine and prednisolone in reducing pathology

Predictors of Poor Perinatal Outcome following Maternal Perception of Reduced Fetal Movements: A Prospective Cohort Study

Background Maternal perception of reduced fetal movement (RFM) is associated with increased risk of stillbirth and fetal growth restriction (FGR). RFM is thought to represent fetal compensation to conserve energy due to insufficient oxygen and nutrient transfer resulting from placental insufficiency. Objective To identify predictors of poor perinatal outcome after maternal perception of reduced fetal movements (RFM). Design Prospective cohort study. Methods 305 women presenting with RFM after 28 weeks of gestation were recruited. Demographic factors and clinical history were recorded and ultrasound performed to assess fetal biometry, liquor volume and umbilical artery Doppler. A maternal serum sample was obtained for measurement of placentally-derived or modified proteins including: alpha fetoprotein (AFP), human chorionic gonadotrophin (hCG), human placental lactogen (hPL), ischaemia-modified albumin (IMA), pregnancy associated plasma protein A (PAPP-A) and progesterone. Factors related to poor perinatal outcome were determined by logistic regression. Results 22.1% of pregnancies ended in a poor perinatal outcome after RFM. The most common complication was small-for-gestational age infants. Pregnancy outcome after maternal perception of RFM was related to amount of fetal activity while being monitored, abnormal fetal heart rate trace, diastolic blood pressure, estimated fetal weight, liquor volume, serum hCG and hPL. Following multiple logistic regression abnormal fetal heart rate trace (Odds ratio 7.08, 95% Confidence Interval 1.31–38.18), (OR) diastolic blood pressure (OR 1.04 (95% CI 1.01–1.09), estimated fetal weight centile (OR 0.95, 95% CI 0.94–0.97) and log maternal serum hPL (OR 0.13, 95% CI 0.02–0.99) were independently related to pregnancy outcome. hPL was related to placental mass. Conclusion Poor perinatal outcome after maternal perception of RFM is closely related to factors which are connected to placental dysfunction. Novel tests of placental function and associated fetal response may provide improved means to detect fetuses at greatest risk of poor perinatal outcome after RFM

The carbon footprint of different modes of birth in the UK and the Netherlands: an exploratory study using life cycle assessment

Objective: To compare the carbon footprint of caesarean and vaginal birth. Design: Life cycle assessment (LCA). Setting: Tertiary maternity units and home births in the UK and the Netherlands. Population: Birthing women. Methods: A cradle-to-grave LCA using openLCA software to model the carbon footprint of different modes of delivery in the UK and the Netherlands. Main Outcome Measures: ‘Carbon footprint’ (in kgCO2 equivalents [kgCO2e]). Results: Excluding analgesia, the carbon footprint of a caesarean birth in the UK was 31.21 kgCO2e, compared with 12.47 kgCO2e for vaginal birth in hospital and 7.63 kgCO2e at home. In the Netherlands the carbon footprint of a caesarean was higher (32.96 kgCO2e), but lower for vaginal birth in hospital and home (10.74 and 6.27 kgCO2e, respectively). Emissions associated with analgesia for vaginal birth ranged from 0.08 kgCO2e (with opioid analgesia) to 237.33 kgCO2e (nitrous oxide with oxygen). Differences in analgesia use resulted in a lower average carbon footprint for vaginal birth in the Netherlands than the UK (11.64 versus 193.26 kgCO2e). Conclusion: The carbon footprint of a caesarean is higher than for a vaginal birth if analgesia is excluded, but this is very sensitive to the analgesia used; use of nitrous oxide with oxygen multiplies the carbon footprint of vaginal birth 25-fold. Alternative methods of pain relief or nitrous oxide destruction systems would lead to a substantial improvement in carbon footprint. Although clinical need and maternal choice are paramount, protocols should consider the environmental impact of different choices

A prospective cohort study providing insights for markers of adverse pregnancy outcome in older mothers

From Springer Nature via Jisc Publications RouterHistory: received 2020-12-16, accepted 2021-09-28, registration 2021-10-07, pub-electronic 2021-10-20, online 2021-10-20, collection 2021-12Publication status: PublishedAbstract: Background: Advanced maternal age (≥35 years) is associated with increased rates of adverse pregnancy outcome. Better understanding of underlying pathophysiological processes may improve identification of older mothers who are at greatest risk. This study aimed to investigate changes in oxidative stress and inflammation in older women and identify clinical and biochemical predictors of adverse pregnancy outcome in older women. Methods: The Manchester Advanced Maternal Age Study (MAMAS) was a multicentre, observational, prospective cohort study of 528 mothers. Participants were divided into three age groups for comparison 20–30 years (n = 154), 35–39 years (n = 222) and ≥ 40 years (n = 152). Demographic and medical data were collected along with maternal blood samples at 28 and 36 weeks’ gestation. Multivariable analysis was conducted to identify variables associated with adverse outcome, defined as one or more of: small for gestational age (< 10th centile), FGR (<5th centile), stillbirth, NICU admission, preterm birth < 37 weeks’ gestation or Apgar score < 7 at 5 min. Biomarkers of inflammation, oxidative stress and placental dysfunction were quantified in maternal serum. Univariate and multivariable logistic regression was used to identify associations with adverse fetal outcome. Results: Maternal smoking was associated with adverse outcome irrespective of maternal age (Adjusted Odds Ratio (AOR) 4.22, 95% Confidence Interval (95%CI) 1.83, 9.75), whereas multiparity reduced the odds (AOR 0.54, 95% CI 0.33, 0.89). In uncomplicated pregnancies in older women, lower circulating anti-inflammatory IL-10, IL-RA and increased antioxidant capacity (TAC) were seen. In older mothers with adverse outcome, TAC and oxidative stress markers were increased and levels of maternal circulating placental hormones (hPL, PlGF and sFlt-1) were reduced (p < 0.05). However, these biomarkers only had modest predictive accuracy, with the largest area under the receiver operator characteristic (AUROC) of 0.74 for placental growth factor followed by TAC (AUROC = 0.69). Conclusions: This study identified alterations in circulating inflammatory and oxidative stress markers in older women with adverse outcome providing preliminary evidence of mechanistic links. Further, larger studies are required to determine if these markers can be developed into a predictive model of an individual older woman’s risk of adverse pregnancy outcome, enabling a reduction in stillbirth rates whilst minimising unnecessary intervention