A research study out of Harvard suggests that men who have a higher dairy consumption from full fat foods such as cheese and cream can show a decrease in their feritlity:
The participants were required to answer a questionnaire which had questions pertaining to their dairy products, fruit, meat and other types of food intake during a typical week.
Also, the researchers tested the men for their sperm quality, speed and shape, only to find that those who ate three or more portions of full-fat dairy food a day had a sperm quality that was 25 percent poorer than those whose consumption of these products were low.
Lead researcher Myriam Afeiche explained that it could be either the female hormone estrogen in milk that comes from the cow, or pesticides which find their way in to dairy products which could be affecting men's fertility.
Read more at http://www.counselheal.com/articles/3154/20121024/cheese-consumption-affect-fertility-men-study.htm#B8W37RvFVRpr6Fwr.99
Will you suggest to your SO that they decrease the amount of dairy they consume?