OBJECTIVE: We conducted a systematic review and meta-analysis to examine the relationship between stillbirth and various perinatal outcomes in subsequent pregnancy. DATA SOURCES: PubMed, the Cochrane Library, Embase, Web of Science, and CNKI databases were searched up to July 2023. STUDY ELIGIBILITY CRITERIA: Cohort studies that reported the association between stillbirth and perinatal outcomes in subsequent pregnancies were included. METHODS: We conducted this systematic review and meta-analysis in accordance with the PRISMA guidelines. Statistical analysis was performed using Rand Stata software. We used random-effects models to pool each outcome of interest. We performed a meta-regression analysis to explore the potential heterogeneity. The certainty (quality) of evidence assessment was performed using the GRADE approach. RESULTS: Nineteen cohort studies were included, involving 4,855,153 participants. From these studies, we identified 28,322 individuals with previous stillbirths who met the eligibility criteria. After adjusting for confounders, evidence of low to moderate certainty indicated that compared with women with previous live births, women with previous stillbirths had higher risks of recurrent stillbirth (odds ratio, 2.68; 95% confidence interval, 2.01-3.56), preterm birth (odds ratio, 3.15; 95% confidence interval, 2.07-4.80), neonatal death (odds ratio, 4.24; 95% confidence interval, 2.65-6.79), small for gestational age/intrauterine growth restriction (odds ratio, 1.3; 95% confidence interval, 1.0-1.8), low birthweight (odds ratio, 3.32; 95% confidence interval, 1.46-7.52), placental abruption (odds ratio, 3.01; 95% confidence interval, 1.01-8.98), instrumental delivery (odds ratio, 2.29; 95% confidence interval, 1.68-3.11), labor induction (odds ratio, 4.09; 95% confidence interval, 1.88-8.88), cesarean delivery (odds ratio, 2.38; 95% confidence interval, 1.20-4.73), elective cesarean delivery (odds ratio, 2.42; 95% confidence interval, 1.82-3.23), and emergency cesarean delivery (odds ratio, 2.35; 95% confidence interval, 1.81-3.06) in subsequent pregnancies, but had a lower rate of spontaneous labor (odds ratio, 0.22; 95% confidence interval, 0.13-0.36). However, there was no association between previous stillbirth and preeclampsia (odds ratio, 1.72; 95% confidence interval, 0.63-4.70) in subsequent pregnancies. CONCLUSION: Our systematic review and meta-analysis provide a more comprehensive understanding of adverse pregnancy outcomes associated with previous stillbirth. These findings could be used to inform counseling for couples who are considering pregnancy after a previous stillbirth.

COVID-19 is not only associated with substantial acute liver and kidney injuries, but also with an elevated risk of post-acute sequelae involving the kidney and liver system. We aimed to investigate whether COVID-19 exposure increases the long-term risk of kidney and liver disease, and what are the magnitudes of these associations. We searched PubMed, Embase, Web of Science, , and the Living Overview of the Evidence COVID-19 Repository for cohort studies estimating the association between COVID-19 and kidney and liver outcomes. Random-effects meta-analyses were performed to combine the results of the included studies. We assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach. Fifteen cohort studies with more than 32 million participants were included in the systematic review COVID-19 was associated with a 35% greater risk of kidney diseases (10 more per 1000 persons; low certainty evidence) and 54% greater risk of liver disease (3 more per 1000 persons; low certainty evidence). The absolute increases due to COVID-19 for acute kidney injury, chronic kidney disease, and liver test abnormality were 3, 8, and 3 per 1000 persons, respectively. Subgroup analyses found no differences between different type of kidney and liver diseases. The findings provide further evidence for the association between COVID-19 and incident kidney and liver conditions. The absolute magnitude of the effect of COVID-19 on kidney and liver outcomes was, however, relatively small.

Background: The clinical efficacy and safety of intravenous immunoglobulin (IVIg) treatment for COVID-19 remain controversial. This study aimed to map the current status and gaps of available evidence, and conduct a meta-analysis to further investigate the benefit of IVIg in COVID-19 patients. Methods: Electronic databases were searched for systematic reviews/meta-analyses (SR/MAs), primary studies with control groups, reporting on the use of IVIg in patients with COVID-19. A random-effects meta-analysis with subgroup analyses regarding study design and patient disease severity was performed. Our outcomes of interest determined by the evidence mapping, were mortality, length of hospitalization (days), length of intensive care unit (ICU) stay (days), number of patients requiring mechanical ventilation, and adverse events. Results: We included 34 studies (12 SR/MAs, 8 prospective and 14 retrospective studies). A total of 5571 hospitalized patients were involved in 22 primary studies. Random-effects meta-analyses of very low to moderate evidence showed that there was little or no difference between IVIg and standard care or placebo in reducing mortality (relative risk [RR] 0.91; 95% CI 0.78-1.06; risk difference [RD] 3.3% fewer), length of hospital (mean difference [MD] 0.37; 95% CI - 2.56, 3.31) and ICU (MD 0.36; 95% CI - 0.81, 1.53) stays, mechanical ventilation use (RR 0.92; 95% CI 0.68-1.24; RD 2.8% fewer), and adverse events (RR 0.98; 95% CI 0.84-1.14; RD 0.5% fewer) of patients with COVID-19. Sensitivity analysis using a fixed-effects model indicated that IVIg may reduce mortality (RR 0.76; 95% CI 0.60-0.97), and increase length of hospital stay (MD 0.68; 95% CI 0.09-1.28). Conclusion: Very low to moderate certainty of evidence indicated IVIg may not improve the clinical outcomes of hospitalized patients with COVID-19. Given the discrepancy between the random- and fixed-effects model results, further large-scale and well-designed RCTs are warranted