My OB suggested I cut back exercise by about 10%, which generally equates to keeping my heart rate below 140 and not "pushing the envelope" every day, in his words. It can be confusing because we see everywhere that fit women should exercise for healthier pregnancies, but I think if you're on this community you're already pretty fit. My OB said that if we continue to "push the envelope", we risk oligomenorrhea, which means we might not ovulate because our bodies simply don't have enough body fat to produce estrogen. Estrogen is a hormone that causes us to ovulate, and without ovulation, we don't produce eggs, and you know the rest of the story. No egg, no baby.

(I'm not a doctor or anywhere close to it. Just asking a lot of questions, like you.)

Good luck!