Smoking reduces the chances that women undergoing IVF fertility treatment will have a baby. Being overweight can also limit the odds of becoming a mother. The current research shows that both smoking and being overweight unfavourably affect the live birth rate after IVF. It is comparable to adding a decade to the reproductive age of a 20-year-old. This means it makes her the equivalent of a 30-year-old non-smoker in reproductive terms. Researchers from the Radboud University Nijmegen Medical Center, Netherlands, examined the success rates of 8,457 women after their first cycle of IVF (in-vitro fertilisation) and life-style factors. Women who were overweight had a 33 percent lower chance of having a child after the first treatment than other patients in the study. The effect of smoking and being overweight were most prominent in women with unexplained sub-fertility, where the reason they do not conceive naturally is not established. This suggests that these women in particular would be able to improve their chances of having a child if they quit smoking and lost weight. The live birth rate of smokers with unexplained sub-fertility was 13 percent. In non-smoking women with the same diagnosis it was 20 percent.
Human Reproduction,
April 2005