Shesadiamond - I'm currently 39 and TTC#1
I had a chemical pregnancy in July last year, after 6 months of simply not using contraception.
2 months later, I conceived again and that pregnancy lasted 11 weeks and 5 days. 5 months after that MC (and 3 months after my cycle got back to normal post MC), I conceived again, miscarrying at 6 weeks.
Now, 5 months on, I am coming to the end of a two week wait and trying not to symptom spot !!
I'm not sure what the point of telling you all this is, other than to say that you CAN conceive at this age, but I think you do have to expect that, due to aged eggs, you have to crack a few open before you find one still in date Perhaps your body is simply more efficient at recognising when an egg is not going to last the course and, as another poster said, is saving you from the heartache that is MC
If you are over 35 and have been trying for 6 months or more, I think you can be referred for fertility investigations, so why not do so - if your previous tests were in the past, perhaps things have changed now ? Perhaps you are not ovulating - that can be tested pretty easily AND treated - worth going through it all again I think, unless the tests were recent.
Good luck