 [ Symptoms ] can blood and a uti affect a pregnancy test  my period is almost 2 months late and i am having some pregnancy symptoms but both tests i have taken are negative during a physical for work the other day the np said i had a severe uti blood and protein in my urine could this be the affecting the test at all [ Disease ] from what i have read about how pregnancy tests work it should not affect a pregnancy test tests look for hcg a hormone present only if you are pregnant here is what i read pregnancy tests are designed to tell if your urine or blood contains a hormone called human chorionic gonadotropin hcg this hormone is produced right after a fertilized egg attaches to the wall of a woman is uterus this usually happens    but not always    about six days after fertilization if you are pregnant levels of hcg continue to rise rapidly doubling every two to three days here is the link <link> good luck