OBJECTIVE: The study aimed to investigate the potential influence of COVID-19 infection on embryo implantation and early development in women undergoing frozen embryo transfer (FET), with a specific focus on infections occurring at different periods around FET.
METHODS: A retrospective analysis was performed on women who had undergone FET during a period marked by a significant surge in COVID-19 infection in Shanghai. All enrolled women experienced their first documented COVID-19 infection around the time of FET, ensuring that infections did not occur prior to oocyte retrieval. Participants were categorized into six groups based on the timing of infection: uninfected, ≥ 60 days, < 60 days before FET, 0-14 days, 15-28 days, and 29-70 days after FET. Clinical outcomes were compared across these groups.
RESULTS: The infection rate among the total of 709 cases was 78.28%. Infected individuals exhibited either asymptomatic or mild symptoms. The ongoing pregnancy rates for the first four groups were 40.7%, 44.4%, 40.5%, and 34.2% (P = 0.709) respectively, biochemical pregnancy rates (59.1% vs. 61.1% vs. 67.6% vs. 55.7%, P = 0.471) and clinical pregnancy rates (49.6% vs. 55.6% vs. 55.4% vs. 48.1%, P = 0.749), all showed no significant differences. Early spontaneous abortion rates across all six groups were 18.3%, 20.0%, 25.0%, 28.9%, 5.4%, and 19.0% respectively, with no significant differences (P = 0.113). Multivariable logistic analysis revealed no significant correlation between the infection and ongoing pregnancy.
CONCLUSIONS: Asymptomatic or mild COVID-19 infections occurring around FET do not appear to have a significant adverse impact on early pregnancy outcomes.

BACKGROUND: Equine herpesvirus type 1 (EHV-1) is commonly associated with horse abortion. Currently, there are no reported cases of abortion resulting from EHV-1 infection in donkeys.
RESULTS: This was the first survey-based study of Chinese donkeys. The presence of EHV-1 was identified by PCR. This survey was conducted in Chabuchar County, North Xinjiang, China, in 2020. A donkey EHV-1 strain (Chabuchar/2020) was successfully isolated in MDBK cells. Seventy-two of 100 donkey sera were able to neutralize the isolated EHV-1. Moreover, the ORF33 sequence of the donkey-origin EHV-1 Chabuchar/2020 strain showed high levels of similarity in both its nucleotide (99.7‒100%) and amino acid (99.5‒100%) sequences, with those of horse EHV-1 strains. EHV-1 Chabuchar/2020 showed significant consistency and was classified within cluster 1 of horse EHV-1 strains. Further, analysis of the expected ORF30 nucleotide sequence revealed that donkey EHV-1 strains contained guanine at position 2254, resulting in a change to aspartic acid at position 752 of the viral DNA polymerase. Therefore, these strains were classified as horse neuropathogenic strains. Lastly, a phylogenetic tree was constructed using the partial ORF68 nucleotide sequences, showing that the identified donkey EHV-1 strain and the EHV-1 strain found in aborted Yili horses in China comprised a novel independent VIII group.
CONCLUSIONS: This study showed the first isolation and identification of EHV-1 as an etiological agent of abortions in donkeys. Further analysis of the ORF33, ORF30, and ORF68 sequences indicated that the donkey EHV-1 contained the neuropathogenic genotype of strains in the VIII group. It is thus important to be aware of EHV-1 infection in the donkey population, even though the virus has only been identified in donkey abortions in China.

OBJECTIVE: To investigate the effect of subacute exposure of Di (2-ethylhexyl) phthalate (DEHP) on endometrial decidualization in mice.
METHODS: CD1 mice were orally administrated with 300 mg·kg－1·d－1 (low-dose group), 1000 mg·kg－1·d－1 (medium-dose group), or 3000 mg·kg－1·d－1 DEHP (1/10 LD50, high-dose group) for 28 days, respectively. The early natural pregnancy model and artificially induced decidualization model were established, and the uterine tissues were collected on D7 of natural pregnancy and D8 of artificially induced decidualization, respectively. The effects of subacute exposure to DEHP on the decidualization of mice were detected by HE staining, Masson staining, TUNEL staining, and Western blotting, respectively. A model of spontaneous abortion was constructed in mice after subacute exposure to 300 mg·kg-1·d-1 DEHP, and the effect of impaired decidualization on pregnancy was investigated by observing the pregnancy outcome on the 10th day of gestation.
RESULTS: Compared with the control group, the conception rate was significantly lower in the high-dose DEHP subacute exposure group. HE staining showed that, compared with the control group, the decidual stromal cells in the low- and medium-dose exposure groups were disorganized, the nuclei of the cells were irregular, the cytoplasmic staining was uneven, and the number of polymorphonuclear cells was significantly reduced. Masson staining showed that compared with the control group, the collagen fibers in the decidua region of the DEHP low-dose group and the medium-dose group were more distributed, more abundant and more disorderly. TUNEL staining showed increased apoptosis in the decidua area compared to the control group. Western blotting showed that the expression of BMP2, a marker molecule for endometrial decidualization, was significantly reduced. The abortion rate and embryo resorption rate were significantly higher, and the number of embryos, uterine wet weight, uterine area and placenta wet weight were significantly lower in mice exposed to 300 mg·kg－1·d－1 DEHP than in control mice stimulated by mifepristone abortifacient drug.
CONCLUSIONS: Subacute exposure to DEHP leads to impaired endometrial decidualization during early pregnancy and exacerbates the risk of adverse pregnant outcomes in mice.
目的: 探究邻苯二甲酸酯类增塑剂邻苯二甲酸二（2-乙基）己酯（DEHP）亚急性暴露对小鼠子宫内膜蜕膜反应和流产风险的影响。方法: 分别选取300、1000、3000 mg·kg－1·d－1三个浓度梯度的DEHP对CD1小鼠进行经口亚急性暴露28 d。建立DEHP亚急性暴露小鼠早期自然妊娠模型和人工诱导假孕小鼠蜕膜反应模型，分别取自然妊娠第7天子宫组织和人工诱导蜕膜反应小鼠妊娠第8天诱导侧子宫组织，通过苏木精-伊红染色（HE染色）、Masson染色、TUNEL染色、蛋白质印迹法检测DEHP亚急性暴露对小鼠蜕膜反应的影响。构建300 mg·kg－1·d－1 DEHP亚急性暴露小鼠自然流产模型，观察妊娠第10天的妊娠结局探究蜕膜反应受损对小鼠妊娠的影响。结果: 与空白对照组比较，DEHP大剂量组受孕率显著性降低；HE染色显示DEHP小剂量组和中剂量组蜕膜基质细胞排列杂乱、细胞核形态不规则、胞浆染色不均、多核细胞数显著性降低；Masson染色显示DEHP小剂量组和中剂量组蜕膜区的胶原纤维分布更多、数量增多、排列杂乱；TUNEL染色显示暴露组蜕膜区细胞凋亡增加；蛋白质印迹法检测显示暴露组子宫内膜蜕膜反应标志分子BMP2蛋白表达水平显著降低；在米非司酮流产刺激下DEHP小剂量组小鼠流产率、胚胎吸收率显著升高，胚胎数、子宫湿重、子宫面积、胎盘湿重显著降低。结论: DEHP亚急性暴露导致小鼠子宫内膜蜕膜反应受损加重小鼠妊娠流产风险。.

This article aims to report the comprehensive and up-to-date analysis and evidence of the insertion rate, expulsion rate, removal rate, and utilization rate of immediate placement of intrauterine devices (IUDs) versus delayed placement after artificial abortion. PubMed, Embase, Cochrane, Web of Science, CNKI, and Wanfang databases were comprehensively searched up to January 12, 2024 for studies that compared immediate versus delayed insertion of IUDs after abortion. The evaluation metrics included the number of IUD insertion after surgical or medical abortions, the frequency of expulsion and removal at 6 months or 1 year, the number of continued usage, pain intensity scores, the number of infections, the duration of bleeding, and instances of uterine perforation during or after IUD insertion. Ten randomized controlled articles were eligible, comprising 11 research projects, of which 3 projects involved the placement of an IUD after surgical abortion, and 8 projects involved the placement of an IUD after medical abortion. This included 2025 patients (977 in the immediate insertion group and 1,048 in the delayed insertion group). We summarized all the extracted evidence. The meta-analysis results indicated that for post-surgical abortions, the immediate insertion group exhibited a higher IUD placement rate than the delayed insertion group. After medical abortions, the immediate insertion group showed higher rates of IUD placement, utilization, and expulsion at 6 months or 1 year. The two groups showed no statistically significant differences in the removal rate, post-insertion infection rate, pain scores during insertion, and days of bleeding during the follow-up period. Compared to delayed placement, immediate insertion of IUDs can not only increase the usage rate at 6 months or 1 year but also enhance the placement rate.

BACKGROUND: Abortion behaviors among individuals with mental disorders presented major obstacles to women\'s health. However, few studies reported the prevalence and associated factors of abortion among women with severe mental disorders in China. Consequently, this study aims to investigate the prevalence of abortion among female patients in rural communities and identify potential health risks.
METHODS: This was a cross-sectional study of 276 women aged 18 years and older with severe mental disorders in rural areas of Shandong Province, China. The pregnancy history, abortion history and socio-demographic characteristics of women were investigated by questionnaire. Logistic regression analysis was employed to examine the associated factors for different abortion behaviors.
RESULTS: The study showed that 82.61 % (228/276) of patients had a pregnancy history. Among the patients with a pregnancy history, 43.42 % (99/228) reported having had at least one abortion, and 15.79 % (36/228) had more than one. In the other side, 31.58 % (72/228) of them experienced spontaneous abortion, while 12.72 % (29/228) experienced induced abortion. Age at first gestation (aOR 0.80, 95 % CI 0.70-0.90) and age at last gestation (aOR 1.17, 95 % CI 1.07-1.27) were both associated with abortion. Anxiety was related to spontaneous (aOR 1.08, 95 % CI 1.02-1.15) and repeat abortions (aOR 1.10, 95 % CI 1.01-1.19). In addition, religion (aOR 10.47, 95 % CI 2.81-39.01), number of children≥2 (aOR 0.18, 95 % CI 0.04-0.77), and family functioning (aOR 1.31, 95 % CI 1.06-1.63) were associated with induced abortion.
CONCLUSIONS: Women with severe mental disorders in rural regions have notably higher rates of abortion compared to the general female population, particularly for spontaneous abortions. Gestational age and anxiety of pregnant patients deserve attention and preventive measures to avoid the outcomes of abortion.

Coxiella burnetii is the causative agent of zoonotic Q fever. Animals are the natural reservoirs of C. burnetii, and domestic livestock represent the major sources of human infection. C. burnetii infection in pregnant females may causes abortion during late pregnancy, whereby massive shedding of C. burnetii with abortion products becomes aerosolized and persists in the environment. Therefore, monitoring and surveillance of this infection in livestock is important for the prevention of the C. burnetii transmission. Previous serological surveys have shown that C. burnetii infection is endemic in livestock in China. However, few data are available on the diagnosis of C. burnetii as a cause of abortion by molecular methods in livestock. To get a better understanding of the impact of C. burnetii infection on domestic livestock in China, a real-time PCR investigation was carried out on collected samples from different domestic livestock suffering abortion during 2021-2023. A total of 338 samples collected from eight herds of five livestock species were elected. The results showed that 223 (66 %) of the collected samples were positive for C. burnetii DNA using real-time PCR. For the aborted samples, 82 % (128/15) of sheep, 81 % (34/42) of goats, 44 % (15/34) of cattle, 69 % (18/26) of camels, and 50 % (17/34) of donkeys were positive for C. burnetii. Besides, 44 % (8/18) and 4 % (1/25) of asymptomatic individuals of sheep and donkey were also positive for C. burnetii. In addition, the positive samples were further confirmed by amplification and sequencing of the C. burnetii-specific isocitrate dehydrogenase (icd) gene. Phylogenetic analysis based on specific gene fragments of icd genes revealed that the obtained sequences in this study were clustered into two different groups associated with different origin of hosts and geographic regions. This is the first report confirming that C. burnetii exists in aborted samples of sheep, goats, cattle, donkeys and camels in China. Further studies are needed to fully elucidate the epidemiology of this pathogen in livestock as well as the potential risks to public health.

OBJECTIVE: Innate lymphoid cells (ILCs) are a class of newly discovered immunocytes. Group 1 ILCs (ILC1s) are identified in the decidua of humans and mice. High mobility group box 1 (HMGB1) is predicted to be one of the target genes of miR-142-3p, which is closely related to pregnancy-related diseases. Furthermore, miR-142-3p and HMGB1 are involved in regulating the NF-κB signaling pathway. This study aimed to examine the regulatory effect of miR-142-3p on ILC1s and the underlying mechanism involving HMGB1 and the NF-κB signaling pathway.
METHODS: Mouse models of normal pregnancy and abortion were constructed, and the alterations of ILC1s, miR-142-3p, ILC1 transcription factor (T-bet), and pro-inflammatory cytokines of ILC1s (TNF-α, IFN-γ and IL-2) were detected in mice from different groups. The targeting regulation of HMGB1 by miR-142-3p in ILC1s, and the expression of HMGB1 in normal pregnant mice and abortive mice were investigated. In addition, the regulatory effects of miR-142-3p and HMGB1 on ILC1s were detected in vitro by CCK-8, Annexin-V/PI, ELISA, and RT-PCR, respectively. Furthermore, changes of the NF-κB signaling pathway in ILC1s were examined in the different groups. For the in vivo studies, miR-142-3p-Agomir was injected in the uterus of abortive mice to evaluate the abortion rate and alterations of ILC1s at the maternal-fetal interface, and further detect the expression of HMGB1, pro-inflammatory cytokines, and the NF-κB signaling pathway.
RESULTS: The number of ILC1s was significantly increased, the level of HMGB1 was significantly upregulated, and that of miR-142-3p was considerably downregulated in the abortive mice as compared with the normal pregnant mice (all P<0.05). In addition, miR-142-3p was found to drastically inhibit the activation of the NF-κB signaling pathway (P<0.05). The number of ILC1s and the levels of pro-inflammatory cytokines were significantly downregulated and the activation of the NF-κB signaling pathway was inhibited in the miR-142-3p Agomir group (all P<0.05).
CONCLUSIONS: miR-142-3p can regulate ILC1s by targeting HMGB1 via the NF-κB signaling pathway, and attenuate the inflammation at the maternal-fetal interface in abortive mice.

Recurrent pregnancy loss is a distressing event during pregnancy, and understanding its causal factors is crucial. Follistatin, a glycoprotein involved in folliculogenesis and embryogenesis, has been implicated as a potential contributor to the risk of spontaneous abortion. However, establishing a causal relationship requires rigorous investigation using robust methods.
In this study, we utilized mendelian randomization (MR), a powerful genetic epidemiological approach, to examine the causal relationship between follistatin levels and spontaneous abortion. We obtained instrumental variables strongly associated with follistatin levels from large-scale genome-wide association from the IEU database. The inverse variance weighting (IVW) method was taken as gold standard. We also performed sensitivity test to evaluate the robustness of our result.
MR analysis revealed a significant causal relationship between low follistatin levels and spontaneous abortion (p = 0.03). Sensitivity analyses, including pleiotropy test, heterogeneity test, and leave-one-out analysis, all supported the robustness of our findings.
Our study provides compelling evidence supporting the causal relationship between low follistatin levels and increased risk of spontaneous abortion. These findings underscore the importance of follistatin in the etiology of spontaneous abortion and suggest potential preventive interventions. Modulating follistatin levels or relevant pathways could hold promise for reducing the incidence of spontaneous abortion and improving reproductive outcomes. The utilization of MRs strengthens the validity of our results by mitigating confounding and reverse causality biases. Further research is needed to elucidate the underlying molecular mechanisms and explore therapeutic strategies targeting follistatin levels.

Hepatitis E virus (HEV) has become one of the important pathogens that threaten the global public health. Type 3 and 4 HEV are zoonotic, which can spread vertically and cause placental damage. At the same time, autophagy plays an important role in the process of embryo development and pregnancy maintenance. However, the relationship between HEV and autophagy, especially in the placenta tissue, has not been clarified. We found lower litter rates in HEV-infected female mice, with significant intrauterine abortion of the embryo (24.19%). To explore the effects of HEV infection on placenta autophagy, chorionic cells (JEG-3) and mice placenta have been employed as research objects, while the expression of autophagy-related proteins (ATGs) has been detected in JEG-3 cells with different times of HEV inoculation. The results demonstrated that the expression of protein LC3 decreased and p62 accumulated, meanwhile ATGs such as ATG4B, ATG5, and ATG9A in JEG-3 cells have decreased significantly. In addition, the maturation of autophagosomes, which referred to the process of the combination of autophagosomes and lysosomes was prevented by HEV infection as well. All processes of autophagic flux, which include the initiation, development, and maturation three stages, were suppressed in JEG-3 cells after HEV infection. Similarly, the protein and gene expression of LC3 were significantly decreased in the placenta of pregnant mice with HEV infection. In summary, our results suggested that HEV inhibited autophagy in JEG-3 cells and placenta of pregnant mice, which might be the important pathogenic mechanisms of HEV infection leading to embryo abortion.

Chlamydiosis and brucellosis induced abortions have resulted in significant economic losses in the global livestock industry. Although there have been numerous reports on these two diseases in ruminants in China, limited information is available regarding the prevalence of Chlamydia abortus (C. abortus) and Brucella spp. infection in pigs. This study aimed to investigate the prevalence of C. abortus and Brucella spp. infections in pig serum using serology and to identify potential risk factors. In total, 2816 serum samples were collected from 12 provinces in China. The presence of C. abortus antibodies was determined using an enzyme-linked immunosorbent assay (ELISA), while the presence of Brucella spp. antibodies was examined using the Rose Bengal Plate Test (RBPT) and the Standard Agglutination Test (SAT). The seroprevalences of C. abortus and Brucella spp. were 8.38 % (236/2816) and 0.11 % (3/2816), respectively. Geographical location, season, and age were found to be risk factors associated with C. abortus infection in pig herds in China (p<0.01), and the seropositive rate for C. abortus in sow herds was strongly associated with the occurrence of abortion (p<0.01). Overall, in China, pigs exhibit a higher seroprevalence of C. abortus, whereas the prevalence of Brucella is limited. This study represents the first comprehensive survey of C. abortus and Brucella spp. in pig herds in China that established potential risk factors and provided data for the prevention and control of intraspecies and interspecies transmission of C. abortus to humans.