If you drink more than five cups of coffee a day, you reduce your chances of achieving pregnancy during IVF treatment by 50 percent," says researcher Ulrik Kesmodel, MD, PHD, a consultant gynecologist at the Fertility Clinic of Aarhus University Hospital in Denmark.
Eating high amounts of saturated fats and polyunsaturated fats also made IVF success less likely, says researcher Jorge E. Chavarro, MD, an assistant professor of nutrition and epidemiology at Harvard School of Public Health.
But eating higher amounts of monounsaturated fats increased the chances of having a live birth, he tells WebMD.
Both studies were presented in Istanbul at the 28th annual meeting of the European Society for Human Reproduction and Embryology (ESHRE).
However, other experts consulted by WebMD warn that both studies are small and it's too soon to recommend drastic dietary changes based on the findings.
"In a small study, all sorts of spurious results can come out," says Richard Paulson, MD, professor of reproductive medicine and head of the fertility program at the University of Southern California in Los Angeles.