Lucia I am 41 and still get plenty of EWCM. Probably more than I had when I was younger!

Could it be that the meds you take for your IVF treatment affect your CM production? I understand Clomid for example, can reduce CM.

Other factors are water consumption - the more you drink the more you have. There are other ways to increase your EWCM (such as taking evening primrose oil capsules in the first half of your cycle) but I gather you are concerned with the amount you are producing naturally?