General Fitness & Nutrition: Marathon Training and Fertility

Women who go under a certain percentage of body fat stop having their periods and are not fertile.  (I can't quite remember the number, and it probably isn't the same for everybody).  This is not a permanant thing, and as soon as you increase your body fat and start getting your periods again, there should be no problem getting pregnant.  I'd tell her to go for it, and if she stops getting her periods to cut back on the training.  This is, of course, if she doesn't otherwise have fertility issues.  If that is the case I'd tell her to go see her OB/Gyn.  Hope that helps