Even with a normal amh, your chances of pregnancy at 40 are about 7 percent. Most of the eggs are not normal, due to age related changes. After age 40-41, the chances of spontaneous pregnancy begin to drop dramatically. The miscarriage rate is 50 percent. This is due to an increased incidence of genetic abnormality of the embryo. If you really want to conceive, your best shot is to see an infertility specialist as soon as possible and consider ART.
An ultrasound finding of multiple small follicles alone does not indicate pco It seems like that would be the only abnormality. For a diagnosis of pco, you would need other abnormal blood work.