Prenatal Exposure to Preeclampsia and Long-Term Ophthalmic Morbidity of the Offspring

A Narrative Review on the Pathophysiology of Preeclampsia

Preeclampsia (PE) is a multifactorial pregnancy disorder characterized by hypertension and proteinuria, posing significant risks to both maternal and fetal health. Despite extensive research, its complex pathophysiology remains incompletely understood. This narrative review aims to elucidate the intricate mechanisms contributing to PE, focusing on abnormal placentation, maternal systemic response, oxidative stress, inflammation, and genetic and epigenetic factors. This review synthesizes findings from recent studies, clinical trials, and meta-analyses, highlighting key molecular and cellular pathways involved in PE. The review integrates data on oxidative stress biomarkers, angiogenic factors, immune interactions, and mitochondrial dysfunction. PE is initiated by poor placentation due to inadequate trophoblast invasion and improper spiral artery remodeling, leading to placental hypoxia. This triggers the release of anti-angiogenic factors such as soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng), causing widespread endothelial dysfunction and systemic inflammation. Oxidative stress, mitochondrial abnormalities, and immune dysregulation further exacerbate the condition. Genetic and epigenetic modifications, including polymorphisms in the Fms-like tyrosine kinase 1 (FLT1) gene and altered microRNA (miRNA) expression, play critical roles. Emerging therapeutic strategies targeting oxidative stress, inflammation, angiogenesis, and specific molecular pathways like the heme oxygenase-1/carbon monoxide (HO-1/CO) and cystathionine gamma-lyase/hydrogen sulfide (CSE/H2S) pathways show promise in mitigating preeclampsia's effects. PE is a complex disorder with multifactorial origins involving abnormal placentation, endothelial dysfunction, systemic inflammation, and oxidative stress. Despite advances in understanding its pathophysiology, effective prevention and treatment strategies remain limited. Continued research is essential to develop targeted therapies that can improve outcomes for both mothers and their babies.

Performance of machine-learning approach for prediction of pre-eclampsia in a middle-income country

OBJECTIVE

Pre-eclampsia (PE) is a serious complication of pregnancy associated with maternal and fetal morbidity and mortality. As current prediction models have limitations and may not be applicable in resource-limited settings, we aimed to develop a machine-learning (ML) algorithm that offers a potential solution for developing accurate and efficient first-trimester prediction of PE.

METHODS

We conducted a prospective cohort study in Mexico City, Mexico to develop a first-trimester prediction model for preterm PE (pPE) using ML. Maternal characteristics and locally derived multiples of the median (MoM) values for mean arterial pressure, uterine artery pulsatility index and serum placental growth factor were used for variable selection. The dataset was split into training, validation and test sets. An elastic-net method was employed for predictor selection, and model performance was evaluated using area under the receiver-operating-characteristics curve (AUC) and detection rates (DR) at 10% false-positive rates (FPR).

RESULTS

The final analysis included 3050 pregnant women, of whom 124 (4.07%) developed PE. The ML model showed good performance, with AUCs of 0.897, 0.963 and 0.778 for pPE, early-onset PE (ePE) and any type of PE (all-PE), respectively. The DRs at 10% FPR were 76.5%, 88.2% and 50.1% for pPE, ePE and all-PE, respectively.

CONCLUSIONS

Our ML model demonstrated high accuracy in predicting pPE and ePE using first-trimester maternal characteristics and locally derived MoM. The model may provide an efficient and accessible tool for early prediction of PE, facilitating timely intervention and improved maternal and fetal outcome. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Short- and Long-Term Outcomes of Preeclampsia in Offspring: Review of the Literature

Preeclampsia is a multisystemic clinical syndrome characterized by the appearance of new-onset hypertension and proteinuria or hypertension and end organ dysfunction even without proteinuria after 20 weeks of pregnancy or postpartum. Residing at the severe end of the spectrum of the hypertensive disorders of pregnancy, preeclampsia occurs in 3 to 8% of pregnancies worldwide and is a major cause of maternal and perinatal morbidity and mortality, accounting for 8-10% of all preterm births. The mechanism whereby preeclampsia increases the risk of the neurodevelopmental, cardiovascular, and metabolic morbidity of the mother's offspring is not well known, but it is possible that the preeclamptic environment induces epigenetic changes that adversely affect developmental plasticity. These developmental changes are crucial for optimal fetal growth and survival but may lead to an increased risk of chronic morbidity in childhood and even later in life. The aim of this review is to summarize both the short- and long-term effects of preeclampsia on offspring based on the current literature.

Expression pattern and clinical significance of microRNA-let-7a and IFN-gamma in placental tissue of patients with preeclampsia with severe features

OBJECTIVES

Preeclampsia with severe features (PECsf) is a common disease in pregnant women. let-7a and IFN-gamma (interferon-gamma) are involved in diagnosis and prognosis of preeclampsia. This study explored effects of let-7a and IFN-gamma on PECsf patients.

METHODS

The placental tissue of 21 PECsf, 19 preeclampsia without severe features (PEC), and 20 normal pregnant women were collected, and clinical data were recorded. let-7a and IFN-gamma expressions in placental tissue were detected. The correlation between let-7a/IFN-gamma expression and clinical indexes was analyzed. According to let-7a and IFN-gamma expressions, PECsf patients were assigned into Hlet-7a group (let-7a high expression group), Llet-7a group (let-7a low expression group), HIFN-gamma group (IFN-gamma high expression group) and LIFN-gamma group (IFN-gamma low expression group). The incidence of adverse prognosis was compared.

RESULTS

let-7a and IFN-gamma were highly expressed in placental tissue of preeclampsia patients, with significant differences between PEC and PECsf. The high expressions of let-7a and IFN-gamma were positively correlated with mean arterial pressure, lactate dehydrogenase, and 24 h urinary protein in placental tissues of PECsf patients. High let-7a and IFN-gamma expressions were correlated with adverse outcomes of PECsf.

CONCLUSIONS

High let-7a and IFN-gamma expressions were correlated with clinical features, and could be used as biomarkers for treatment and poor prognosis of PECsf.

Expression and significance of let-7a and tumor necrosis factor-alpha in placenta of severe preeclampsia

OBJECTIVE

To investigate the expression and clinical significance of let-7a and tumor necrosis factor-alpha (TNF-α) in placental tissue of patients with severe preeclampsia (SPE).

METHODS

From January 2018 to October 2019, 64 cases of puerperal delivery at the First People's Hospital of Lianyungang City, 44 cases of SPE (SPE group), and 20 cases of healthy pregnant women (NC group) were selected. QRT-PCR and Western-blot were used to detect the expression levels of let-7a, TNF-αmRNA, and protein in the two groups of placental tissues. The correlation and the clinical significance of the two were statistically analyzed.

RESULTS

The relative expression of let-7a in the SPE group was significantly lower than that in the control group (0.06 ± 0.02 versus 0.25 ± 0.04, p < .05); the expression of TNF-αmRNA in the SPE group was significantly higher than that in the control group (0.48 ± 0.04 versus 0.17 ± 0.03, p < .05); TNF-α protein expression was significantly increased in the SPE group (1.09 ± 0.12 versus 0.56 ± 0.03, p < .05); let-7a and TNF-α were significantly negatively correlated (r = -0.41, p < .05); the blood pressure and birth weight of the pregnant women in the SPE group and the control group were significantly different [systolic blood pressure (164.27 ± 4.62) mmHg versus (125.01 ± 2.23)] mmHg, diastolic blood pressure (109.24 ± 2.97) mmHg versus (75.94 ± 2.74) mmHg, neonatal birth weight (2507.02 ± 161.46) g versus (3592.12 ± 153.05) g, p < .05]; the expression of TNF-α in placental tissue of SPE group was significantly positively correlated with systolic and diastolic blood pressure (r = 0.93 and 0.89, p < .05).

CONCLUSION

let-7a may participate in the occurrence and development of SPE by negatively regulating the expression of TNF-α.

Assisted reproductive technology and long-term ophthalmic morbidity of the offspring

In this study, we investigate if children born following assisted reproduction technologies (ARTs) are at an increased risk for long-term ophthalmic complications. For this purpose, a population-based cohort analysis was conducted which included all deliveries between 1991 and 2014 at a single tertiary medical center. Offspring were classified relative to conception method as ART or spontaneous pregnancies. Offspring hospitalizations up to the age of 18 years involving ophthalmic morbidities were evaluated according to a predefined set of ICD-9 codes. A Kaplan-Meier survival curve was used to compare cumulative hospitalization rates in exposed (ART) and unexposed offspring (spontaneous), and a Cox proportional hazards model was used to control for potential confounders. A total of 243,682 deliveries were included in the study. In that, 1.8% of the deliveries (4364) were of mothers who underwent fertility treatments and 98.2% (239,318) were conceived spontaneously. Offspring born to mothers who underwent fertility treatments had a significantly higher hospitalization rate involving ophthalmic morbidity, as compared to spontaneously conceived offspring (1.2% vs. 1.0%, p = 0.04). The Kaplan-Meier survival curve pointed to a significantly higher cumulative incidence of ophthalmic morbidity following ART (log rank p = 0.02). Cox proportional hazards model was adjusted for maternal age, preterm delivery, maternal hypertensive disorders, diabetes, and mode of delivery which demonstrated ART as an independent risk factor for long-term pediatric ophthalmic morbidity (adjusted hazard ratio = 1.37, CI 1.04-1.80, p-value = 0.02). We concluded that ART is an independent risk factor for long-term ophthalmic morbidity of the offspring.