MTHFR C677T polymorphism is associated with follicle-stimulating hormone levels and controlled ovarian hyperstimulation response: a retrospective study from the clinical database

Objective: To evaluate the impact of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with clinical data analysis in controlled ovarian hyperstimulation (COH) of infertile women in the Intravenous Infusion Safety Evaluation Center of Hunan Province, People's Republic of China. Design: Genetic Association Study. Setting: Reproductive medicine clinical. Patient(s): This genetic association study included 722 infertile women who received the standard long treatment protocol with accessible and complete electronic medical records. Intervention(s): None. Main Outcome Measure(s): The clinical parameters were obtained from the Intravenous Infusion Safety Evaluation center. Result(s): Basal FSH levels in the TT group were significantly higher than those of the CC group. The FSH levels after down-regulation in the TT group were higher than those of CC/CT genotypes. The TT genotype patients received significantly higher total doses of GnRH agonist and FSH compared with CC/CT genotypes, whereas the total dose of hCG was higher in the CT genotypes compared with the CC/TT genotypes. Further association analysis between hormone levels and COH outcomes indicated significantly negative correlation of basal FSH levels with antral follicle count and number of oocytes as well as the down-regulation FSH levels with the number of metaphase II oocytes and oocytes. Conclusion(s): The MTHFR C677T polymorphism was associated with high doses of ovarian stimulation medications, as well as higher FSH levels. The negative correlation between FSH levels and the number of oocytes suggested that C677T polymorphism may play a role in the poor prognosis of COH oocytes. This needs to be studied in future prospective studies with longer follow-up. ((C) 2019 by American Society for Reproductive Medicine.)