You may need a transfusion of red blood cells if you have lost a lot of blood or your red blood cell count is low (anemia). You may need a platelet transfusion if your platelet count is low (thrombocytopenia). White blood cell transfusions are rare and are only done in very specific situations.
1 So, the earlier after a missed period you take a HPT, the harder it is to spot the hCG. 2  If you wait one week after a missed period to test, you are more apt to have an accurate result. 3  Also, testing your urine first thing in the morning may boost the accuracy. When you use them â The amount of hCG in a pregnant womanâs urine increases with time. 2  So, the earlier after a missed period you take a HPT, the harder it is to spot the hCG. 3  If you wait one week after a missed period to test, you are more apt to have an accurate result.
A good rule of thumb is to wait at about 21 days (three weeks) after you last had unprotected sex/birth control failure before using a home pregnancy test -- or at least one day after a missed period. On average, 20mIU/hCG levels are present about seven to ten days past ovulation.