The study identifies a gap in the literature regarding

The gap

Evidence profile

Stated in the limitations and future work and recommendations and discussion and cells research gap and cells future research sections of the source papers, classified as general, spanning 5 journals.

Supporting evidence — 7 representative gaps

• Modified myocardial performance index (Mod-MPI) as a Doppler-derived marker for fetal cardiac dysfunction in diabetic and preeclamptic pregnancies (2026) · Egyptian Journal of Radiology and Nuclear Medicine · doi

  The relatively small sample size in each group may limit the generalizability of the findings. Second, the cross- sectional design precludes assessment of temporal rela- tionships and long-term perinatal outcomes, preventing causal inferences. Potential confounding factors may also have influenced Mod-MPI measurements. The relatively wide gestational age range (20–38  weeks), although Mod-MPI is consid- ered relatively gestational-age independent, may still have introduced variability that was not adjusted for sta- tistically. In addition, maternal factors such as body mass index, degree of glycemic control, severity and onset of preeclampsia, and medication use (e.g., insulin or antihy- pertensive therapy) were not stratified or controlled for, which may have influenced fetal cardiac function. Furthermore, decreased fetal perception was based on subjective maternal reporting and may be subject to recall bias. Although all measurements were performed by a single experienced blinded operator using a stand- ardized protocol, formal intra-observer reproducibility analysis was not conducted. Finally, the absence of adjust- ment for potential hemodynamic and biochemical con- founders limits the ability to fully isolate the independent effect of GDM and preeclampsia on Mod-MPI. Future prospective longitudinal studies with larger cohorts and multivariate analysis are needed to better control for these confounders and clarify the independ- ent predictive value of Mod-MPI.

  generalstated in limitationsevidence 5/5
  Keywords: relatively potential factors influenced measurements gestational independent maternal control preeclampsia fetal small sample size group
• Association between the serum uric acid-to-creatinine ratio index and the risk of preeclampsia in advanced maternal age pregnant women: a retrospective cohort study (2026) · Frontiers in Cardiovascular Medicine · doi

  Future work should (1) develop and externally validate prediction models that integrate SUA/sCr with blood pressure, renal markers, and other clinical parameters in women of advanced maternal age; (2) establish prospective cohorts with repeated measurements across gestation to better define temporal patterns; and (3) assess whether modifiable factors or interventions that influence SUA/sCr are associated with reduced preeclampsia risk, with standardized capture and adjustment for key medication exposures (including aspirin prophylaxis and antihypertensive therapy).

  generalstated in future workevidence 5/5
  Keywords: future develop externally validate prediction models integrate blood pressure renal markers clinical parameters women advanced
• Association between the serum uric acid-to-creatinine ratio index and the risk of preeclampsia in advanced maternal age pregnant women: a retrospective cohort study (2026) · Frontiers in Cardiovascular Medicine · doi

  Ethics statement This study has several limitations. First, given the retrospective observational design, residual confounding cannot be fully eliminated and causal inference is not possible. Second, our inclusion/exclusion criteria may have introduced selection bias and limited external validity because we excluded women with chronic hypertension, and other comorbidities that commonly coexist with advanced maternal age; therefore, the findings are most applicable to women with advanced maternal age who had singleton spontaneous pregnancies and were free of these major comorbidities at baseline. Third, to reduce reverse causality, SUA and sCr were measured at the initial antenatal visit (median 12.0 weeks; IQR: 10.1–13.8 weeks) and no SUA/sCr measurements occurred after a preeclampsia diagnosis; however, subclinical pathophysiological changes may precede clinical diagnosis, so reverse causality cannot be completely excluded. Finally, several important confounders were unavailable or could not be reliably ascertained, including pre-pregnancy BMI, smoking, socioeconomic indicators, diet, physical activity, and exposure during some pregnancy (notably aspirin prophylaxis, antihypertensive agents, urate-lowering therapy, and other drugs affecting renal function or uric acid metabolism) was not systematically recorded and could not be adjusted for. conditions. Medication chronic The studies involving humans were approved by Changde Hospital, Xiangya School of Medicine, Central South University (The first people’s hospital of Changde city)(approval number: 2024-190-01). The studies were conducted in accordance with the local legislation and institutional requirements. The human samples used in this study were acquired from primarily isolated as part of your previous study for which ethical approval was obtained. Written informed consent for participation was not required legal guardians/next of kin in accordance with the national legislation and institutional requirements.

  generalstated in limitationsevidence 5/5
  Keywords: several cannot excluded women chronic comorbidities advanced maternal reverse causality weeks diagnosis pregnancy changde hospital
• Adverse pregnancy outcomes in hypertensive disorders of pregnancy: an in-depth comparison between subtypes (2026) · Frontiers in Medicine · doi

  for • Preeclampsia is gestational hypertension accompanied by ≥1 new-onset conditions at or after 20 weeks’ gestation. Eclampsia is defined as seizures in a pregnant woman with preeclampsia with no other identifiable cause. Preeclampsia and eclampsia are classified in the same category (preeclampsia-eclampsia, PE). • Chronic hypertension (CH) refers to high BP predating the pregnancy or recognized at <20 weeks’ gestation. • Gestational hypertension (GH) is persistent de novo hypertension that develops at or after 20 weeks’ gestation in the absence of features of preeclampsia. • Chronic hypertension with superimposed preeclampsia (CHSP) is chronic hypertension with development of new proteinuria and/or organ or uteroplacental dysfunction(s). In this study, the APOs included anemia, diabetes mellitus, preterm birth, low birthweight, hemorrhage disorder, infection, liver disease, stillbirth and neonatal death, maternal near-miss, kidney disease, heart disease, pulmonary disease, embolism, and maternal death. The definitions of the above APOs were consistent with the WHO standards (17, 18). 2.3 Ethics approval and consent to participate The Medical Ethics Committee of Hunan Provincial Maternal and Child Health Care Hospital approved the study (NO: 2024-S155). The Hunan Provincial Health Commission routinely collected surveillance data, and the government has developed the “Maternal Near Miss Surveillance Working Manual” to collect those data. It is a retrospective study of medical records; all data were fully anonymized before we accessed them. Moreover, we de-identified the patient records before analysis. Since the Government routinely collects these data, the need for informed consent to participate was waived. We confirmed that all operations were following relevant guidelines and regulations.

  generalstated in recommendationsevidence 5/5
  Keywords: preeclampsia hypertension maternal surveillance weeks gestation eclampsia chronic apos disease near miss hunan provincial health
• The influence of hydroxychloroquine on the risk of pre-eclampsia, hypertension, and premature delivery in patients with systemic lupus erythematosus during pregnancy: a meta-analysis (2026) · European Journal of Clinical Pharmacology · doi

  Second, the widespread use of low-dose aspirin (LDA) for pre-eclampsia prophylaxis in high-risk pregnancies may have confounded the results [30]; LDA was commonly used across studies but was rarely stratified or adequately adjusted for in analyses, and the inability to disentangle its independent effect from that of HCQ represents a major limitation.

  generalstated in discussionevidence 5/5
  Keywords: second widespread dose aspirin eclampsia prophylaxis high risk pregnancies confounded commonly used across rarely stratified
• Hypertensive Disorders and Perinatal Outcomes According to Age Groups at Advanced Maternal Age (2026) · Muğla Sıtkı Koçman Üniversitesi Tıp Dergisi · doi

  The study identifies a gap in the literature regarding the relationship between advanced maternal age and hypertensive disorders, pregnancy complications, and perinatal outcomes. - The study aims to fill this gap by providing a comparative analysis of hypertensive disorders, pregnancy complications, and perinatal outcomes in advanced maternal age pregnancies.

  generalstated in cells research gapevidence 5/5
  Keywords: study identifies gap literature regarding relationship between advanced
• Hypertensive Disorders and Perinatal Outcomes According to Age Groups at Advanced Maternal Age (2026) · Muğla Sıtkı Koçman Üniversitesi Tıp Dergisi · doi

  Future studies should examine the relationship between advanced maternal age and hypertensive disorders, pregnancy complications, and perinatal outcomes in different populations. - Future studies should investigate the effectiveness of preventive strategies and proactive management of risk factors in reducing maternal and perinatal complications in advanced maternal age pregnancies.

  generalstated in cells future researchevidence 4/5
  Keywords: future studies examine relationship between advanced maternal age

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