Cannabis Exposure and Adverse Pregnancy Outcomes Related to Placental Function.

Importance: Cannabis use is increasing among reproductive-age individuals and the risks associated with cannabis exposure during pregnancy remain uncertain. Objective: To evaluate the association between maternal cannabis use and adverse pregnancy outcomes known to be related to placental function. Design, Setting, and Participants: Ancillary analysis of nulliparous individuals treated at 8 US medical centers with stored urine samples and abstracted pregnancy outcome data available. Participants in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be cohort were recruited from 2010 through 2013; the drug assays and analyses for this ancillary project were completed from June 2020 through April 2023. Exposure: Cannabis exposure was ascertained by urine immunoassay for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol using frozen stored urine samples from study visits during the pregnancy gestational age windows of 6 weeks and 0 days to 13 weeks and 6 days (visit 1); 16 weeks and 0 days to 21 weeks and 6 days (visit 2); and 22 weeks and 0 days to 29 weeks and 6 days (visit 3). Positive results were confirmed with liquid chromatography tandem mass spectrometry. The timing of cannabis exposure was defined as only during the first trimester or ongoing exposure beyond the first trimester. Main Outcome and Measure: The dichotomous primary composite outcome included small-for-gestational-age birth, medically indicated preterm birth, stillbirth, or hypertensive disorders of pregnancy ascertained by medical record abstraction by trained perinatal research staff with adjudication of outcomes by site investigators. Results: Of 10 038 participants, 9257 were eligible for this analysis. Of the 610 participants (6.6%) with cannabis use, 32.4% (n = 197) had cannabis exposure only during the first trimester and 67.6% (n = 413) had ongoing exposure beyond the first trimester. Cannabis exposure was associated with the primary composite outcome (25.9% in the cannabis exposure group vs 17.4% in the no exposure group; adjusted relative risk, 1.27 [95% CI, 1.07-1.49]) in the propensity score-weighted analyses after adjustment for sociodemographic characteristics, body mass index, medical comorbidities, and active nicotine use ascertained via urine cotinine assays. In a 3-category cannabis exposure model (no exposure, exposure only during the first trimester, or ongoing exposure), cannabis use during the first trimester only was not associated with the primary composite outcome; however, ongoing cannabis use was associated with the primary composite outcome (adjusted relative risk, 1.32 [95% CI, 1.09-1.60]). Conclusions and Relevance: In this multicenter cohort, maternal cannabis use ascertained by biological sampling was associated with adverse pregnancy outcomes related to placental dysfunction.

Impact of villitis of unknown etiology and adverse acute neonatal outcomes in Eastern Ontario.

INTRODUCTION: Villitis of unknown etiology (VUE) is a histopathological lesion associated with adverse neonatal outcomes. We seek to define the obscure relationship between the severity and distribution of VUE and adverse neonatal outcomes. METHODS: A retrospective chart review was conducted of pathologic findings from singleton placentas diagnosed with VUE between 2013 and 2019. Control placentas were matched 1:1 for gestational age and presence/absence of fetal IUGR. Neonatal outcomes of interest included: newborn resuscitation, NICU admission, Apgar scores and cord blood acidosis. Odds ratio and 95 % confidence intervals were calculated with controls as the reference. RESULTS: 452 placentas were included. 35 % of pregnancies were complicated by IUGR. When analyzed by severity (low-grade: OR = 4.75 [2.86-8.14]; high-grade: OR = 4.76 [2.71-8.79]) and distribution (focal: OR = 5.24 [2.87-10.17]; multifocal: OR = 4.90 [2.90-8.59]), VUE was significantly associated with need for newborn resuscitation. No other neonatal outcomes of interest were significantly associated with VUE diagnosis. DISCUSSION: We determined a statistically significant association between VUE severity and distribution and the need for newborn resuscitation. VUE lesions were not associated with any additional neonatal outcomes of interest. Further studies with larger sample sizes are required to confirm these associations for obstetric and neonatal case management.

Machine learning-based placental clusters and their associations with adverse pregnancy outcomes.

BACKGROUND: Placental abnormalities have been described in clinical convenience samples, with predominately adverse outcomes. Few studies have described placental patterns in unselected samples. OBJECTIVE: We aimed to investigate associations between co-occurring placental features and adverse pregnancy outcomes in a prospective cohort of singletons. METHODS: Data were from the Safe Passage study (U.S. and South Africa, 2007-2015). Before 24 weeks' gestation, participants were randomly invited to donate placental tissue at delivery for blinded, standardised pathological examination. We used hierarchical clustering to construct statistically derived groups using 60 placental features. We estimated associations between the placental clusters and select adverse pregnancy outcomes, expressed as unadjusted and adjusted risk ratios (RRs) and robust 95% confidence intervals (CI). RESULTS: We selected a 7-cluster model. After collapsing 2 clusters to form the reference group, we labelled the resulting 6 analytic clusters according to the overarching category of their most predominant feature(s): severe maternal vascular malperfusion (n = 117), fetal vascular malperfusion (n = 222), other vascular malperfusion (n = 516), inflammation 1 (n = 269), inflammation 2 (n = 175), and normal (n = 706). Risks for all outcomes were elevated in the severe maternal vascular malperfusion cluster. For instance, in unadjusted analyses, this cluster had 12 times the risk of stillbirth (RR 12.07, 95% CI 4.20, 34.68) and an almost doubling in the risk of preterm delivery (RR 1.93, 95% CI 1.27, 2.93) compared with the normal cluster. Small infant size was more common among the abnormal clusters, with the highest unadjusted RRs observed in the fetal vascular malperfusion cluster (small for gestational age birth RR 2.99, 95% CI 2.24, 3.98, head circumference <10th percentile RR 2.86, 95% CI 1.60, 5.12). Upon adjustment for known risk factors, most RRs attenuated but remained >1. CONCLUSION: Our study adds to the growing body of epidemiologic research, finding adverse pregnancy outcomes may occur through etiologic mechanisms involving co-occurring placental abnormalities.

Serum amyloid A1 and pregnancy zone protein in pregnancy complications and correlation with markers of placental dysfunction.

BACKGROUND: Hypertensive disorders of pregnancy (preeclampsia, gestational hypertension, and chronic hypertension), diabetes mellitus, and placental dysfunction confer an increased risk of long-term maternal cardiovascular disease. Preeclampsia is also associated with acute atherosis that involves lesions of uteroplacental spiral arteries, resembling early stages of atherosclerosis. Serum amyloid A1 is involved in hypercoagulability and atherosclerosis and may aggregate into amyloid-aggregations of misfolded proteins. Pregnancy zone protein may inhibit amyloid aggregation. Amyloid is involved in Alzheimer's disease and cardiovascular disease; it has been identified in preeclampsia, but its role in preeclampsia pathophysiology is unclear. OBJECTIVE: We hypothesized that serum amyloid A1 would be increased and pregnancy zone protein decreased in hypertensive disorders of pregnancy and diabetic pregnancies and that serum amyloid A1 and pregnancy zone protein would correlate with placental dysfunction markers (fetal growth restriction and dysregulated angiogenic biomarkers) and acute atherosis. STUDY DESIGN: Serum amyloid A1 is measurable in both the serum and plasma. In our study, plasma from 549 pregnancies (normotensive, euglycemic controls: 258; early-onset preeclampsia: 71; late-onset preeclampsia: 98; gestational hypertension: 30; chronic hypertension: 9; diabetes mellitus: 83) was assayed for serum amyloid A1 and pregnancy zone protein. The serum levels of angiogenic biomarkers soluble fms-like tyrosine kinase-1 and placental growth factor were available for 547 pregnancies, and the results of acute atherosis evaluation were available for 313 pregnancies. The clinical characteristics and circulating biomarkers were compared between the pregnancy groups using the Mann-Whitney U, chi-squared, or Fisher exact test as appropriate. Spearman's rho was calculated for assessing correlations. RESULTS: In early-onset preeclampsia, serum amyloid A1 was increased compared with controls (17.1 vs 5.1 µg/mL, P<.001), whereas pregnancy zone protein was decreased (590 vs 892 µg/mL, P=.002). Pregnancy zone protein was also decreased in diabetes compared with controls (683 vs 892 µg/mL, P=.01). Serum amyloid A1 was associated with placental dysfunction (fetal growth restriction, elevated soluble fms-like tyrosine kinase-1 to placental growth factor ratio). Pregnancy zone protein correlated negatively with soluble fms-like tyrosine kinase-1 to placental growth factor ratio in all study groups. Acute atherosis was not associated with serum amyloid A1 or pregnancy zone protein. CONCLUSION: Proteins involved in atherosclerosis, hypercoagulability, and protein misfolding are dysregulated in early-onset preeclampsia and placental dysfunction, which links them and potentially contributes to future maternal cardiovascular disease.

Association of distinct features of villitis of unknown etiology histopathology and fetal growth restriction diagnosis in a retrospective cohort from Eastern Ontario.

INTRODUCTION: Villitis of unknown etiology (VUE) is associated with fetal growth restriction (FGR) and adverse short-term neonatal outcomes. No investigation to date has found which VUE features are driving the association with FGR diagnosis. METHODS: A retrospective cohort study of placenta pathology specimens (2013-2017) was conducted. Independent variables of interest were: VUE distribution (focal vs diffuse), location (basal vs non-basal), and grade (high vs low). The primary outcome was FGR, and secondary outcomes were neonatal intensive care unit (NICU) admission, NICU length of stay, Apgar scores <7 at 1, 5, and 10-min, and recurrence rate of villitis in subsequent pregnancies. Association between VUE characteristics and our primary outcome were investigated using logistic regression. Secondary outcomes were explored with regression analyses and recurrence rate of VUE for members of the cohort with a recorded subsequent pregnancy was calculated. RESULTS: One hundred and twenty seven placentas were included. Adjusted models showed no difference in the odds of FGR between high-grade versus low-grade VUE [aOR 1.25 95% CI (0.50, 3.26), p = 0.6], focal/multi-focal vs diffuse cases [aOR 1.03 95% CI (0.28, 4.34), p = >0.9], and basal vs non-basal VUE [aOR 0.06 95% CI (0.00, 1.10), p = 0.058]. After adjusting for prematurity <37 weeks, there were lower odds of NICU admission in basal vs non-basal cases [aOR 0.25, 95% CI (0.06, 0.90), p = 0.048). There was no difference in the odds of neonates presenting with Apgar <7 for the distinct VUE histopathology features. Three cases had recurrent VUE, resulting in a 6.8% [95% CI (3.02%, 10.61%)] recurrence rate. All recurrent cases were high-grade and identified with basal localization. DISCUSSION: There are no statistical associations between distinct VUE features and FGR diagnosis, however location of villitis may be associated with worse neonatal outcomes. Villitis of any type (severity, degree, location) could potentially drive insufficient placental function and poor fetal growth.

Recurrence risk of villitis of unknown etiology: Analysis of a large retrospective cohort study, systematic review and meta-analysis.

INTRODUCTION: Recurrence risk of villitis of unknown etiology (VUE) remains uncertain because of few studies and their methodologic limitations. We calculated recurrence risk in a large population of deliveries after minimizing important biases and compared it to others via systematic review and meta-analysis. METHODS: Over 11 years of placenta pathology reports on singleton deliveries were retrieved and searched for 'villitis' or 'VUE'. Cases of acute villitis and chronic villitis from infections were eliminated via pathologist review. Reports were merged to data containing gestational age, parity and gravida. Recurrence risk of VUE per patient, per parity and per gravida was determined among patients with ≥2 placentas examined for deliveries ≥20 weeks gestation. Results were compared to those from articles and their references identified by a MEDLINE® search. Recurrence risks among methodologically similar studies were pooled using a random effects model. RESULTS: Among 29 124 placenta pathology reports from 27 087 patients, there were 2423 cases of VUE among 2382 patients, of which 153 had ≥2 placentas examined. There were 41 recurrent cases of VUE for a recurrence risk of 27% per patient, 22% per parity, and 19% per gravida. We identified 64 articles, of which 4 were retained. One examined all placentas from all births over a ∼3-year period, finding a recurrence risk of 27%. The remaining 3 studies, along with our own, used indications for placental examination and had a pooled recurrence risk of 30% (95% Confidence Interval: 0.21-0.41). DISCUSSION: In our study, which is the largest, most comprehensive, and methodologically robust to date, VUE recurrence risk was ∼30%.

Multifoetal gestations mediate the effect of in vitro fertilisation (IVF) on ischaemic placental disease in autologous oocyte IVF more than donor oocyte IVF.

BACKGROUND: Ischaemic placental disease (IPD) affects 16%-23% of pregnancies in the United States. In vitro fertilisation (IVF) is a risk factor for IPD, and the magnitude of increase in risk differs for individuals using donor oocytes (donor IVF) versus their own oocytes (autologous IVF). In addition, multifoetal gestations, which are more common in IVF than non-IVF pregnancies, also are a risk factor for IPD. OBJECTIVE: To quantify the contribution of multifoetal gestations to the association between IVF and IPD. METHODS: We conducted a retrospective cohort study at a tertiary hospital from 1 January, 2000 to 1 August 2018 using electronic medical records and state vital statistics data. IPD was defined as preeclampsia, placental abruption, small for gestational age (SGA) birth or an intrauterine foetal demise due to placental insufficiency. We used mediation analysis to decompose the total effect of IVF on IPD into a natural direct effect and an indirect effect through multifoetal gestations. We repeated the analyses separately for donor and autologous IVF. All models were adjusted for maternal age, race, parity, insurance, year of delivery and account for multiple pregnancies per person. RESULTS: We identified 86,514 deliveries, of which 281 resulted from donor IVF and 4173 resulted from autologous IVF. IVF pregnancies had 1.99 (95% CI 1.88, 2.10) times the risk of IPD compared to non-IVF pregnancies, and 75.5% of this increased risk was mediated by multifoetal gestations. Autologous IVF pregnancies had 1.95 (95% CI 1.84, 2.07) times the risk of IPD compared to non-IVF pregnancies, and the per cent mediated was 78.8%. Donor IVF pregnancies had 2.50 (95% CI 2.09, 2.92) times the risk of IPD, but the per cent mediated was 37.5%. CONCLUSION: The majority of the association between autologous IVF and IPD was mediated through multifoetal gestations; however, this was not the case for donor IVF pregnancies.

M1 macrophages involved in the pathogenesis of placental chronic villitis of unknown etiology.

INTRODUCTION: Placental villitis is characterized by the presence of inflammatory infiltrate in the placental villous. The objective of this study was to characterize in villitis of unknown etiology (VUE) of the human placentas the subpopulation of M1, important effector cells, and M2 macrophages, immunoregulatory cells. METHODS: Sixteen cases of VUE and three control placentas were examined using immunohistochemistry with antibodies for CD3, CD68, CD11c, and CD163. RESULTS: CD11c appeared predominantly in the inflamed villi when compared to the normal areas (p<.001). These cells corresponded to 41.2% of the macrophage population in the inflamed area and were mainly present inside the villi (36%). With regards to CD163, these cells tended to be in higher amounts in the inflamed villi when compared to CD11c and normal areas. DISCUSSION: We conclude that the almost exclusive presence of M1 macrophages in the inflamed areas suggests the influence of these cells in the pathogenesis VUE. The greater amount of M2 in villitis and normal areas suggests a possible immunoregulatory mechanism of the inflammatory process in VUE.

Villitis of unknown etiology (VUE): effect on placental size and association with clinical parameters.

OBJECTIVES: Villitis of unknown etiology (VUE) is an inflammatory placental lesion with immune-mediated pathogenesis, diagnosed by histopathological examination. It is one of the three placental lesions which tend to recur in subsequent pregnancies, the other two being chronic histiocytic intervillositis and massive fibrin deposition. The frequency of VUE and its association with maternal, obstetric and neonatal complications are variability reported in the literature. The aim of this study is to determine the frequency of VUE in the population studied and to observe the association of specific subtypes of villitis with clinical features, placental morphometric and microscopic parameters. METHODS: Placentas where villitis was observed, were obtained from the pathology database from January 2013 to June 2018. VUE was graded as low grade (LG), high grade (HG) and basal villitis (BV) and subcategorized based on extent and cell type. Its association with selected maternal, neonatal and placental parameters was evaluated. RESULTS: A total of 1603 placentas were received and 163 singleton placentas with villitis (10%) were reported. LG and HG villitis was observed in 58% and 25% cases respectively. Basal villitis was seen in 24% and pure basal villitis without involvement of parenchymal villi was seen in 16.6%. While there was near equal distribution of focal (n = 45) and multifocal (n = 50) LG villitis, diffuse HG villitis (n = 32) was more common than patchy HG villitis (n = 9). Overall villitis was more common in preterm pregnancies (59.5%) with most of them being basal villitis and low-grade villitis (64.2%, p value .029). None of the other maternal and neonatal parameters had any significance. Placental dimensions (length and breadth) showed a significant negative association with VUE, especially high-grade and multifocal low-grade villitis. CONCLUSION: VUE was a common finding in preterm births and its novel association with placental size opens avenues for further research on alternative mechanisms involved in the association between villitis, placental function and adverse pregnancy outcomes.

Pandemic stress and SARS-CoV-2 infection are associated with pathological changes at the maternal-fetal interface.

INTRODUCTION: The reported effects of SARS-CoV-2 on pregnancy outcomes are conflicting; studies frequently overlook the placenta, which is critical for the health of the mother and infant(s). This study aimed to determine the effect of pandemic stress ± SARS CoV-2 infection on placental histopathology. METHODS: Women were recruited in Canada (n = 69); France (n = 21) or in the UK (n = 25), between March and October 2020. Historic controls (N = 20) were also included. Placenta and fetal membrane samples were collected rapidly after delivery and were fixed and stained for histopathological analysis. Maternal demographical data and obstetric outcomes were recorded. RESULTS: Over 80% of the placentas from SARS-CoV-2+ pregnancies had histopathological abnormalities: predominantly structural (71-86%) or inflammatory (9-22%), depending on geographical location. Excessive fibrin was seen in all sites, whereas deciduitis (Canada), calcifications (UK), agglutinations and chorangiosis (France) predominated in different locations. The frequency of abnormalities was significantly higher than in SARS-CoV-2 negative women (50%, p < 0.05). Demographic and obstetric data were similar in the SARS-CoV-2+ women across all sites - characterised by predominantly Black/Middle Eastern women, and women with elevated body mass index. DISCUSSION: Overall, the frequency of placental abnormalities is increased in SARS-CoV-2+ women, but the incidence of placental abnormalities is also higher in SARS-CoV-2- women that gave birth during the pandemic, which highlights the importance of appropriate control groups to ascertain the roles of pandemic stress and SARS-CoV-2 infection on the placenta and pregnancy outcomes.

Clinical characteristics and risk factors of mirror syndrome: a retrospective case-control study.

BACKGROUND: Mirror syndrome (MS) is a rare obstetric disorder complicated with high maternal morbidity and fetal mortality. MS is often misdiagnosed or underdiagnosed due to the low incidence and lack of awareness of its diverse features. This study aimed to summarise the etiology, clinical characteristics, and risk factors of MS among mothers with fetal hydrops. METHODS: This retrospective case-control study included 37 pregnant women with fetal hydrops in the second and third trimesters from 58,428 deliveries performed at the Third Affiliated Hospital of Sun Yat-Sen University between January 2012 and December 2020. Cases were categorized as MS and non-MS according to the presence or absence of maternal mirroring symptoms. Binary logistic regression was performed for analysis. RESULTS: Fourteen women developed MS with an overall incidence of 0.024% (14/58,428) and 37.8% (14/37) in the fetal hydrops cases. Among the 11 MS cases with known associated etiologies, seven had alpha thalassemia major. Onset of fetal hydrops was later (27.8 vs. 23.0 weeks) and the rate of placental thickening was higher (85.7% vs. 34.8%) in the MS group than in the non-MS group (P < 0.05). Regarding maternal characteristics, the MS group had higher maternal morbidity (85.7% vs. 8.7%), more weight gain (9.0 vs. 5.5 kg), higher rates of hypertension (35.7 vs. 0%) and proteinuria (64.3% vs. 4.3%), and lower levels of hemoglobin (88 vs. 105 g/L) and serum albumin (25.8 vs. 35.0 g/L) than the non-MS group (P < 0.05). Logistic regression analysis showed that onset of fetal hydrops at ≥24 weeks and placental thickening were associated with the risk of MS among fetal hydrops cases (OR 15.83, 95% CI 1.56-160.10 and OR 8.63, 95% CI 1.29-57.72, respectively). CONCLUSIONS: MS is relatively common among fetal hydrops cases in the late second and third trimesters, and alpha thalassemia major is the main etiology for fetal hydrops and also MS in this population. Complicated with high maternal morbidity, the key maternal features of MS include more weight gain, hemodilution, and hypertension. Among those with fetal hydrops, the onset time of ≥24 weeks and placental thickening are risk factors for MS.

Placental lesions and SARS-Cov-2 infection: Diffuse placenta damage associated to poor fetal outcome.

INTRODUCTION: Pregnant women with covid-19 are more likely to experience preterm birth. The virus seems to be associated with a wide range of placental lesions, none of them specific. METHOD: We collected cases of Covid-19 maternal infection during pregnancy associated with poor pregnancy outcomes, for which we received the placenta. We studied clinical data and described pathological findings of placenta and post-mortem examination of fetuses. We performed an immunohistochemical study and RT-PCR of SARS-Cov-2 on placenta samples. RESULTS: We report 5 cases of poor fetal outcome, 3 fetal deaths and 2 extreme premature neonates, one with growth restriction, without clinical and biological sign of SARS-Cov-2 infection. All placenta presented massive perivillous fibrin deposition and large intervillous thrombi associated with strong SARS-Cov-2 expression in trophoblast and SARS-CoV-2 PCR positivity in amniotic fluid or on placenta samples. Chronic histiocytic intervillositis was present in 4/5 cases. Placental ultrasound was abnormal and the sFLT1-PIGF ratio was increased in one case. Timing between mothers' infection and the poor fetal outcome was ≤10 days in 4 cases. The massive placental damage are directly induced by the virus whose receptors are expressed on trophoblast, leading to trophoblast necrosis and massive inflammation in villous chamber, in a similar way it occurs in diffuse alveolar damage in adults infected by SARS-Cov-2. DISCUSSION: SARS-Cov-2 can be associated to a rare set of placental lesions which can lead to fetal demise, preterm birth, or growth restriction. Stronger surveillance of mothers infected by SARS-Cov-2 is required.

Examining the Relationship Between Gastroschisis and Placental Fetal Vascular Malperfusion.

INTRODUCTION: Gastroschisis is a congenital malformation characterized by intestinal herniation through an abdominal wall defect. Despite its unknown pathogenesis, known risk factors include maternal smoking, alcohol use, and young maternal age. Previous work has shown that gastroschisis is associated with placental delayed villous maturation, and the goal of this study was to assess for additional associated placental pathologies that may help clarify the pathogenesis of gastroschisis. METHODS: We conducted a retrospective slide review of 29 placentas of neonates with gastroschisis. Additionally, we reviewed pathology reports from one control group of 30 placentas with other congenital malformations. Gross and histological data were collected based on a standardized rubric. RESULTS: Gastroschisis was associated with increased placental fetal vascular malperfusion (FVM) in 62% of cases (versus 0% of controls, p < 0.0001). It was also associated with increased placental villous maldevelopment in 76% of cases (versus 3% of controls, p < 0.0001). CONCLUSION: Our study demonstrates an association between gastroschisis and FVM. While FVM could be the consequence of vascular disruption due to the ventral location of gastroschisis, it could also reflect estrogen-induced thrombosis in early pregnancy. Further research is needed to separate these possibilities and determine the cause of the placental FVM observed in gastroschisis.

Third trimester stillbirth during the first wave of the SARS-CoV-2 pandemic: Similar rates with increase in placental vasculopathic pathology.

Whether early SARS-CoV-2 definitively increases the risk of stillbirth is unknown, though studies have suggested possible trends of stillbirth increase during the pandemic. This study of third trimester stillbirth does not identify an increase in rates during the first wave of the pandemic period, however investigation of the placental pathology demonstrates trends towards more vascular placental abnormalities.

One-Sided Chronic Intervillositis of Unknown Etiology in Dizygotic Twins: A Description of 3 Cases.

Chronic intervillositis of unknown etiology (CIUE) is a rare, poorly understood, histopathological diagnosis of the placenta that is frequently accompanied by adverse pregnancy outcomes including miscarriage, fetal growth restriction, and intrauterine fetal death. CIUE is thought to have an immunologically driven pathophysiology and may be related to human leukocyte antigen mismatches between the mother and the fetus. Dizygotic twins with one-sided CIUE provide an interesting context to study the influence of immunogenetic differences in such cases. The main immune-cell subsets were investigated using immunohistochemistry. We identified three dizygotic twin pregnancies in which CIUE was present in only one of the two placentas. Two of the pregnancies ended in term delivery and one ended in preterm delivery. Presence of CIUE was correlated with lower placental weight and lower birthweight. Relative number of CD68, CD56, CD20, and CD3 positive cells were comparable between co-twins. The presence of one-sided CIUE in dizygotic twin pregnancy was associated with selective growth restriction in the affected twin. This suggests a unique fetal immunogenetic contribution to the pathogenesis of CIUE. Further study of dizygotic and monozygotic placentas affected by CIUE could identify new insights into its pathophysiology and into the field of reproductive immunology.

Placental diseases associated with assisted reproductive technology.

The placenta develops from the outer trophoblastic layer following the differentiation of the fertilized ovum and is therefore more susceptible to epigenetic regulatory changes caused by environmental interventions and influences during assisted reproductive technology. Furthermore, the placenta regulates the development of the fetal heart, brain, kidneys, bones, and other tissues and organs [1]. Placental dysplasia leads to poor perinatal outcomes as well as long-term health risks later in life, including neurodevelopmental disorders, tumors, and adult metabolic syndrome [2,3]. In view of the decisive role of the placenta during intrauterine fetal development, Graham J. Burton, an expert in placentology from the University of Cambridge, formally proposed the theory of "placenta-derived chronic diseases" in 2018 based on embryonic-derived diseases [4]. In this review, we summarized the changes in placental morphology and structure, growth dynamics, imprinted and non-imprinted genes, and other aspects attributable to assisted reproduction technology. Our review provides a theoretical basis for further research on placental changes caused by assisted reproductive technology that are most strongly associated with an increased risk of neonatal long-term diseases.

Prospective evaluation of first-trimester screening strategy for preterm pre-eclampsia and its clinical applicability in China.

OBJECTIVES: To evaluate, in a Chinese population, the performance of a screening strategy for preterm pre-eclampsia (PE) using The Fetal Medicine Foundation (FMF)'s competing-risks model and to explore its clinical applicability in mainland China. METHODS: This was a prospective, multicenter, observational cohort study including 10 899 women with singleton pregnancy who sought prenatal care at one of 13 hospitals, located in seven cities in mainland China, between 1 December 2017 and 30 December 2019. Mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI) and maternal serum levels of placental growth factor (PlGF) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 13 + 6 weeks' gestation were measured and converted into multiples of the median using Chinese reference ranges. Individualized risk for preterm PE was calculated using the FMF algorithm. Prior risk was calculated based on maternal demographic characteristics and obstetric history. We evaluated the efficiency of the screening strategy using various combinations of biomarkers and analyzed its predictive performance for a composite of placenta-associated adverse pregnancy outcomes, including PE, placental abruption, small-for-gestational age (SGA) and preterm birth, at fixed false-positive rates for preterm PE. RESULTS: We identified 312 pregnancies that developed PE, of which 117 cases were diagnosed as preterm PE (< 37 weeks' gestation). There were 386 pregnancies complicated by severe composite placenta-associated adverse outcome, including preterm PE, 146 cases of severe SGA (birth weight < 3rd percentile) neonate, 61 cases with placental abruption and 109 cases of early preterm birth < 34 gestational weeks. The triple-marker model containing biomarkers MAP, UtA-PI and PAPP-A achieved, at fixed false-positive rates of 10%, 15% and 20%, detection rates for preterm PE of 65.0%, 72.7% and 76.1%, respectively, and detection rates for severe composite placenta-associated adverse outcome of 34.7%, 41.7% and 46.4%, respectively. Replacing PAPP-A with PlGF or adding PlGF to the model did not improve the performance. Of women screening positive for preterm PE at a fixed 5% false-positive rate, an estimated 30% developed at least one placenta-associated adverse pregnancy outcome, including PE, placental abruption, SGA (birth weight < 10th percentile) and preterm birth < 37 weeks. CONCLUSIONS: The FMF competing-risks model for preterm PE was found to be effective in screening a mainland Chinese population. Women who screened positive for preterm PE had increased risk for other placenta-associated pregnancy complications. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Elevated serum progesterone during in vitro fertilization treatment and the risk of ischemic placental disease.

BACKGROUND: Elevated progesterone on the day of human chorionic gonadotropin (hCG) administration is associated with decreased live birth rates in IVF cycles. The association with adverse pregnancy outcomes is unknown. OBJECTIVES: Assess the association between serum progesterone on the day of hCG administration and the risk of ischemic placental disease [IPD; preeclampsia, placental abruption, and/or small for gestational age (SGA)]. METHODS: We conducted a retrospective cohort study of autologous fresh IVF cycles resulting in delivery between 2005 and 2018. All IVF procedures were conducted at a large, university-affiliated infertility center. Patients were divided into tertiles based on their serum progesterone level on the day of hCG administration; the lowest tertile served as the reference group. We identified pregnancies complicated by preeclampsia and placental abruption using ICD-9/10 codes and medical record review. We defined SGA as < 10th percentile using U.S. growth curves. RESULTS: The cohort included 166 deliveries in the lowest tertile of progesterone (0.2-0.73 ng/ml), 166 deliveries in the middle (0.64-1.05 ng/ml) and 167 deliveries in the highest tertile (1.05-5.6 ng/ml). Compared with the lowest tertile, the risk of IPD was greater in the middle (RR 1.6; 95% CI 1.1-2.5) tertile after adjustment for age, parity, number of oocytes retrieved, and estradiol. The highest tertile was also not associated with an increased risk of IPD. CONCLUSION: In an IVF population, elevated serum progesterone in the range of 0.64-1.05 ng/mL on the day of hCG administration was associated with a small increased risk of IPD.