rent between the two groups of pregnant women (all P>0.05). However, the total duration of labor in the SVT seizure group during pregnancy was shorter and pre-pregnancy weight was lower (all P less then 0.05). The rate of cesarean section in pregnant women with SVT attack was 12/16, and the rate of cesarean section in pregnant women without SVT was 50% (23/46; P=0.051). No pregnant woman had an arrhythmia during delivery. Conclusions SVT episode in patients during pregnancy most occurs in the third trimester. Patients who are asymptomatic before pregnancy may also have SVT during pregnancy. Pre-excitation syndrome patients with SVT attacks during pregnancy increase adverse pregnancy outcomes. Multidisciplinary comprehensive management could effectively control pregnant women with pre-excitation syndrome, effectively reduce the occurrence of serious arrhythmia risk events during pregnancy, so that most patients could get good pregnancy outcomes.Objective To explore the clinical application value and accuracy of cell-free fetal DNA (cff-DNA) technique in prenatal screening. Methods The results of quantitative fluorescent PCR (QF-PCR) and karyotype of amniotic fluid cells were analyzed retrospectively in 2 398 monocyesis pregnant women who had been amniocentesis at the First Affiliated Hospital of Zhengzhou University from May 2013 to December 2019, and the results of 359 cases who had been examined by single-nucleotide polymorphism array (SNP array). Results Cff-DNA test of 2, 398 cases indicated 987 cases of trisomy 21, 351 cases of trisomy 18, 135 cases of trisomy 13, 566 cases of sex chromosome abnormality, and 359 cases of other chromosome abnormality. Chromosome karyotype analysis detected 826 cases of trisomy 21, 213 cases of trisomy 18, 17 cases of trisomy 13, 221 cases of sex chromosome abnormality, and 26 cases of other chromosome abnormality. The detection rate were 83.69% (826/987), 60.68% (213/351), 12.59% (17/135), 39.04% (221/566) and 7DNA.Objective To study the correlation between the duration of labor and postpartum hemorrhage. Methods The delivery data of singleton first-term pregnant women who delivered vaginally at Beijing Obstetrics and Gynecology Hospital from January 1, 2017 to December 31, 2017 were collected, 3 104 cases met inclusion criteria. According to the duration of the first labor (t), they were divided into two groups t≥8 hours was the observation group, t less then 8 hours was the control group. In order to ensure the baseline characteristics of the subjects in the two groups were balanced, propensity score matching (PSM) was adopted, with matching ratio 1∶1. Then the observation group was divided into four subgroups group 8-12 h, group 12-16 h, group 16-20 h, group ≥20 h. According to the presence or absence of labor intervention (oxytocin use, artificial rupture of membranes, labor analgesia), the observation group and control group were divided into non-labor intervention observation group, non-labor intervention control ervention and atonic postpartum hemorrhage also increase, which could serve as a clinical warning that excessive labor intervention may indicate a higher incidence of atonic postpartum hemorrhage.Objective To investigate and analyze disease status and risk factors of venous thromboembolism (VTE) during pregnancy and puerperium in our country. Methods Clinical datas were collected from 575 patients diagnosed with VTE during pregnancy and puerperium and hospitalized in nine medical institutions in our country from January 1, 2015 to November 30, 2019, and retrospectively analyzed it's disease status and risk factors.  https://www.selleckchem.com/products/vit-2763.html  Results (1) The proportion of VTE in pregnancy and puerperium was 50.6% (291/575) and 49.4% (284/575), respectively. Four patients died, the mortality rate was 0.7% (4/575). The cause of death was pulmonary embolism. (2) The location of VTE during pregnancy and puerperium was mainly in the lower limb vascular (76.2%, 438/575), followed by pulmonary vessels (7.1%, 41/575). (3) In the risk factors of VTE, cesarean section accounted for 32.3% (186/575), maternal advance age accounted for 27.7% (159/575), braking or hospitalization during pregnancy accounted for 13.6% (78/575), other risk factors accounted for more than 5% were previous VTE, obesity, preterm birth, assistant reproductive technology conception and so on, pre-eclampsia and multiple pregnancy accounted for 4.9% (28/575) respectively. In addition, some patients with VTE did not have any of the above risk factors, and the incidence rate was as high as 23.1% (133/575). Conclusions The occurrence of VTE during pregnancy and puerperium is related to multiple risk factors, and could lead to matemal death, It is very necessary to screen VTE risk factors for all pregnant women, to make corresponding prevention and control measures.Objective To explore the clinical characteristics and gene variation of primary coenzyme Q10 deficiency-7 (COQ10D7) in children. Methods Clinical data and genetic tests results of a COQ10D7 child caused by coenzyme Q4 (COQ4) gene variation at the First Affiliated Hospital of Xiamen University in March 2020 were collected and analyzed. A literature search with "primary coenzyme Q10 deficiency" or "COQ4 gene" as the keyword was conducted at Wanfang database, China national knowledge infrastructure(CNKI), PubMed, online Mendelian inheritance in man(OMIM), ClinVar database (up to April 2020), the clinical characteristics and gene variation of children with primary COQ10D7 were summarized. Results A 5-month-old boy was diagnosed as "epilepsy" because of intermittent epileptic seizures in three months. He had feeding difficulties, growth retardation, hypotonia of limbs and increased lactic acid. His whole exon gene testing suggested a homozygous variation of COQ4 gene (c.370G>A). One article in Chinese and 9 articllevation. Primary COQ10D7 is caused by homozygous or compound heterozygous variation in the COQ4 gene, and c.370G>A may be the hotspot variation in children in southern China.Objective To investigate the clinical phenotype and genotype of transient infantile hypertriglyceridemia (HTGTI). Methods The clinical data of two HTGTI children, diagnosed at Children's Hospital of Fudan University from July 2019 to January 2020, were collected and analyzed retrospectively. The literature up to 25th January 2020 were searched in PubMed, CNKI and Wanfang databases with the key words of "hypertriglyceridemia" and "glycerol phosphate dehydrogenase-1 (GPD1)". Results Two children, including a 5-month-old female and a 13-month-old male, who presented with hepatomegaly, hypertriglyceridemia, transaminase elevation and hepatic steatosis, were admitted to the hospital. Gene detection found compound heterozygous variation of GPD1. After a low-fat diet with enriched medium-chain fatty acids, their plasma triglyceride level were significantly decreased, and finally normalized in case 2. Literature review found 17 patients with GPD1 gene variation reported in 5 papers, including 16 HTGTI cases and one case of different phenotype.