Beyond body mass index: a synthesis of lifestyle factors that may influence in vitro fertilisation outcomes

There are several lifestyle factors that are thought to potentially impact in vitro fertilisation outcomes, including body mass index, smoking, alcohol consumption, caffeine, dietary patterns and physical activity. Eligibility criteria for in vitro fertilisation in England often require individuals to be non-smokers, drug free and have a body mass index of over 30. Some researchers have questioned the scientific and ethical basis for the use of body mass index thresholds in fertility treatment, citing evidence that other factors may have a greater effect on the chance of success of in vitro fertilisation. This article aims to briefly synthesise the current evidence on how other factors such as smoking, alcohol, recreational drugs, smoking, caffeine, dietary patterns and physical activity may impact in vitro fertilisation outcomes.