Linia nigra is not so common in unmarried women , are your
thyroid levels under control with the medicine you are taking , do you have other symptoms of PCOS/PCOD .
Mam, this needs assessment and advice so that this vertical line can be treated and for any other underlining problem.
I understood your concern and noted the problem as well .I need to ask few more details to make a diagnosis and start treatment and advice which suits you. Pl consult me on Practo , so that I can help you better.book a time slot as per your convenience for consultation.