https://www.selleckchem.com/products/hmpl-504-azd6094-volitinib.html Adoption of the TOEVA suggested framework by head and neck surgeons without prior experience in laparoscopic/robotic techniques is feasible resulting in nearly 100% of surgeries accomplished endoscopically. To assess the relationship between age at menarche and the numerical abnormalities of chorionic villi chromosomes in patients with missed abortion. Unexplained miscarriage patients were admitted to an outpatient clinic in Tianjin Central Hospital of Gynecology Obstetrics, China. Embryonic villi tissues were collected aseptically after curettage. Chromosome analysis was performed subsequently using multiplex ligation-dependent probe amplification method. Among 459 cases of missed abortion, chromosome numerical abnormalities were found in 231 cases (50.33%). Autosomal trisomy occurs most frequently, with 16-trisomy being most common. Patients (age more than 35 years old) had more frequent miscarriages compared with those who were less than 35 years old. However, there was no statistically significant difference in chromosome numerical abnormalities. In addition, compared with patients less than 30 years old, women with age ≥ 30 years old had higher abortions frequency (P = 0.002), and the proportion of chromosome numeric abnormalities increased (P = 0.000). The number of patients with abnormal chromosomes is higher among patients whose age of menarche are less than 12 years old than that of patients whose age of menarche was over 12 years old (P = 0.003). Chromosome numerical abnormalities are important cause of missed abortion. The incidence of chromosome numeric abnormalities increases among patients ≥30 years old. Besides, age of menarche is an important risk factor for chromosome numerical abnormalities. Chromosome numerical abnormalities are important cause of missed abortion. The incidence of chromosome numeric abnormalities increases among patients ≥30 years old. Besides, age of menarche is