A study by the University of Nevada, Reno, has found that excess coffee (and other caffeine products) can affect female fertility.
The study involved 9,000 Dutch women and concluded that drinking four or more cups of coffee a day can have astronomical side effects.
Scientists suggest that coffee reduces muscle activity in the Fallopian tubes, thus affecting the transportation of eggs from the ovaries to the womb.
The research was published in the British Journal of Pharmacology and is expected to help with the treatment of pelvic inflammation and sexually transmitted diseases.
Prof. Sean Ward, who was heavily involved in the study, said: "This finding goes a long way towards explaining why drinking caffeinated drinks can reduce a woman's chance of becoming pregnant. This provides an intriguing explanation as to why women with high caffeine consumption often take longer to conceive than women who do not consume caffeine."