Sometimes, a small sample of tissue may be taken with small tools inserted through the vagina during a transvaginal ultrasound. In all three types of pelvic ultrasound, the transducer sends the reflected sound waves to a computer, which makes them into a picture that is shown on a video screen.
So the number of egg-containing follicles remaining in the ovary undergoes a steady decline from an average of 400,000 eggs at age eighteen to an average of 25,000 eggs by age thirty-seven. After age thirtyseven or thirty-eight, there is then a very dramatic acceleration of the monthly decline of remaining eggs.
During my sister's first pregnancy, she went to the hospital bc she had an mc. But it wasn't until then that she found out she was pg with twins and only lost one of them! Turns out she ovulates two eggs each month and there is a good chance she could get preg with twins every time.