Brief Answer:
Hi,

Detailed Answer:

Out of multiple reasons for prolonged period like certain medicines, fibroid of uterus, certain medical conditions like thyroid dysfunction etc. can result into prolonged periods. Hence, it is all the more necessary to find the cause & treatment done accordingly.
Still, some of the common cause should be taken care of. Most common of these is, use of female hormonal medicines, out of which Birth control pills are the commonest cause. Change in periods like absent periods, prolonged or short periods, heavy or light period, vaginal irregular spotting may be present normally for first few months of starting the birth control pills, which may be present even up to 6 months or so. However, if the prolonged bleeding is more heavy or present with agonising symptoms of pain, giddiness, palpitation etc. then you are advised to consult your doctor & treatment done accordingly.

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