Hello, I had a transvaginal ultrasound which showed a trace of fluid in the Pouch of Douglas, but was otherwise normal. The report said: essentially normal pelvis . I ve also had mild lower backache for the past 6 weeks (it comes and goes) and a yeast infection for the past 4 months (I ve tried everything), if that is relevant. Should I be concerned about the trace of fluid in the POD? The US was done on the 7th day of my period, so it is unlikely that it is due to ovulation . I am 20 yrs old. Thank you!