What is the problem if the control line on an ovulation test strip is very faint and very faint?

Patient's question:

No

Doctor's answer:

The control line is very faint, which is common in two situations: First, the test line is very deep, absorbing all the colored substances, leaving little colored material for the control line to absorb. Second, the test strip is about to expire. Since the test line is also very faint in your case, the second situation is more common.