Can an ovarian cyst cause a false positive pregnancy test?

No: Blood or urine pregnancy test is often performed in premenopausal women who have an ovarian cyst. Ovarian cysts are common during pregnancy, but ovarian cysts are not known to cause a false-positive test. False-positive pregnancy tests are rare, with only a handful of possible causes.

Very rarely: If the ovarian cyst is in a tumor making HCG, then it may cause false positive pregnancy test. For practical purposes the answer is: No.

No: Benign or functional Ovarian cysts do not produce hormones and therefore cannot cause a positive pregnancy test. There are some rare ovarian tumors that can produce bHCG and cause a false pregnancy test.