If the fertilized egg is formed early, it can be detected by taking a blood test for HCG. If the HCG level increases, this is a sign of pregnancy and should be reviewed. If the HCG level doubles every other day, it means that the gestational sac is well developed. If you want to use a morning pregnancy test, you should test with morning urine only when your period is delayed for about 7 days, which is more accurate. If your period is often delayed, it is not accurate to test after 1 week of delayed menstruation.