First-Morning Urine

First-morning urine is the sample of urine that is expelled immediately after waking up in the morning and is recommended for use with most home pregnancy tests. This is because the first urine a pregnant woman produces in a day contains the highest concentration of human chorionic gonadotropin (hCG). Therefore, using the first-morning urine can better predict pregnancy in its early stages when hCG levels are at their lowest.