The purpose of this study was to evaluate the international scientific output on postpartum depression (PPD) research during 2000–2020 through a bibliometric analysis and to explore research hotspots, frontiers, and trends in the field of postpartum depression. We searched the Web of Science Core Collection for publications on postpartum depression published between 2000 and 2020. CiteSpace, gCluto, and other software applications were used to analyze the data by year, journal, and country. A total of 2,963 publications were retrieved and 96 countries or regions published related papers. The United States had the largest number of published papers and the highest betweenness centrality, which is the dominant position in the field of postpartum depression. A total of 717 journals published papers, with the Archives of Womens Mental Health ranked first in terms of volume and betweenness centrality. In this study, 31 high-frequency main MeSH terms/subheadings were selected. The high-frequency MeSH terms were clustered into six categories: an overview of depression-related research, diagnostic and screening scales for postpartum depression, epidemiological investigation into postpartum depression, treatment and drug selection for postpartum depression, psychological research on postpartum depression, and etiology, physiopathology, complications, genetics of postpartum depression. Finally, we used strategic diagram to analyze research trends in postpartum depression. This study has identified a continuous significant increase in the publication of PPD articles. Currently, the etiology, physiological pathology, intervention and treatment of complications on PPD are immature, which provides reference for the trend of obstetric psychology.

INTRODUCTION:The aim of the study was to investigate the effects of human semen on the proliferation, survival, migration and invasion of HeLa cervical cancer cells by analyzing the extracellular regulated protein kinase (ERK) pathway.MATERIAL AND METHODS:HeLa cells were stimulated with different concentrations of human semen. MTT assay was used to analyze the effects on cell proliferation. Apoptosis in the different experimental groups was quantified by Annexin V-FITC/PI staining. The effect of seminal plasma on in vitro invasiveness of cells was evaluated using transwell assay. Western blotting was used to evaluate ERK pathway activation.RESULTS:Human semen promoted HeLa cell proliferation; ERK1/2 phosphorylation and c-myc expression also increased with increasing semen concentration. U0126 inhibited semen-induced ERK1/2 phosphorylation, c-myc upregulation and cell proliferation. Compared with the control group, semen did not significantly affect the apoptotic rate of HeLa cells (p > 0.05). The transwell assays showed that compared with the control group, the number of invading cells increased significantly with increasing semen concentration, and the difference was significant (p < 0.05) when 1 : 50 semen was added, suggesting that semen promotes the invasion of cervical cancer cells. Western blotting indicated that ERK1/2 phosphorylation began to increase when 1 : 100 semen was added; with increasing semen concentration, ERK1/2 phosphorylation was significantly up-regulated, and the expression of its downstream target gene, c-myc, was also up-regulated (p < 0.05).CONCLUSIONS:Semen promoted the proliferation of HeLa cells by activating the ERK pathway and showed increased tumorigenic potential in vivo. Human seminal plasma might be a potential factor contributing to the development of cervical cancer.