Hello Fola, Welcome Back to HealthcareMagic Forum
Pouch of Douglas or Cul de Sac is the space between your Uterus and Rectum
. Normally The free fluid is found in this pouch after you have ovulated or if there is rupture of any ovarian cyst
. It is also found in some inflammatory conditions in your Pelvis like Pelvic Inflammatory Disease
. Get yourself examined by a Gynecologist for further evaluation to rule out if it is just a free fluid or if there is any clotted blood. If you don't have any abdominal cramps or fever, then there shouldn't be any issue.
Just get yourself examined once to rule out any pathology. And, one more thing, Free fluid in Cul de Sac as such does not cause infertility
Good Luck and Take Care.