Hi. There can be various causes of fluid collection in pouch of Douglas... both physiological or pathological. I would like to know was a regular scan or u had symptoms like pain in lower abdomen or vaginal discharge or missed menstrual period. If above symptoms r present chances of pathological fluid collection is there. Causes may include pelvic inflammatory disease or tubo ovarian abscess or ectopic pregnancy. Otherwise physiological causes can be ruptured ovarian follicle or increased ovarian permeability due to oestrigen surge. Regarding conceiving again, u must try to have sexual contact on alternate days during the period of ovulation.Besides u can monitor ovulation timing i.e. follicle rupture timing accurately on ultrasound, which can help u in proper planning of sexual intercourse.