Maternal lifestyle and nutritional habits are associated with oocyte quality and ICSI clinical outcomes

Research question Is there an influence of maternal lifestyle factors on the incidence of oocyte dimorphisms and the outcomes of intracytoplasmic sperm injection (ICSI) cycles? Design A total of 752 female patients undergoing ICSI cycle, in a private university-affiliated in vitro fertilization center, from January/2015 to December/2019, were included in this historical cohort study. Prior to start of controlled ovarian stimulation (COS), participants answered a questionnaire regarding cigarette smoking habit, consumption of items such as alcoholic beverages, refined sugar, artificial sweetener, soft drinks, fruits, legumes and vegetables, milk and dairy, and meats, and exercise frequency over the past 6 months. Oocyte morphology was evaluated before ICSI. The influence of maternal lifestyle factors on the incidence of oocyte dimorphisms and ICSI outcomes was evaluated by multivariate general linear models and generalized linear models, adjusted for potential confounders. The main outcome measures were the incidence of oocyte dimorphisms per cycle and clinical outcomes. Results Lifestyle factors and nutritional habits such as cigarette smoking, and the consumptions of alcohol, refined sugar, and artificial sweetener were positively associated with incidence of several oocyte dimorphisms and negatively associated with the response to COS and embryo development. Negative relationships were also observed between those habits and pregnancy outcomes, apart from miscarriage rate, in which positive relationships were observed. Significant negative dose-dependent relationships between those habits and implantation rate were noted. The intake of alcoholic beverages also showed inverse dose-dependent relationships with pregnancy and live-birth rates. Live-birth rate was also negatively associated with cigarette smoking, in a dose-dependent manner. Conclusions Bad maternal habits were associated with reduced oocyte quality and ICSI outcomes. Many of those associations were shown to be dose-dependent.