How long has human urine been studied for biological clues?

Healers, physicians and novices began examining human urine to glean insight into our biological processes about 6,000 years ago. It is believed that physicians of ancient Egypt were first to discover that urine could detect a woman's pregnancy.
The woman urinated on a pile of barley and wheat. If increased estrogen levels caused the seeds to sprout, that meant she was expecting. Not only did this mark the beginning of the medical urine exam, but even more importantly, the beginning of laboratory medicine itself.
Since then, more than 6,000 years of examining urine followed. This medical discipline is now known as urinalysis.