How long after cohabitation can an early pregnancy test be used?

Patient's question:

No

Doctor's answer:

If the menstrual period is one week early or delayed, it is normal. With a history of sexual activity, if the menstrual period is delayed by more than one week, the first step is to use a pregnancy test to rule out pregnancy. Stress, cold exposure, environmental changes, or endocrine disorders can all cause delayed menstruation.