what could be the main cause of abnormal periods in women which continues over 20 days?

Answers:
Possibly a problem with the thyroid gland.

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This is called Dysfunctional uterine bleeding(DUB) in which period lasts more than the regular days (3-5 days) for no apparent reasons. DUB is heavy or irregular menstrual bleeding that is not caused by an underlying anatomical abnormality. In most cases, it is associated with menstruation that occurs without ovulation.When ovulation does not occur, the level of estrogen and progesterone in the uterus is disturbed, leading to DUB.
A woman who bleeds for longer than a week, bleeds more than every 3 weeks or so, bleeds between periods, or bleeds excessively should see a doctor or other health care provider.
DUB is usually painless and is generally not a problem unless the woman is upset by the bleeding or is trying to conceive.
Hormone therapy typically involves oral contraceptives or progesterone therapy to regulate bleeding patterns. Treatment depends on the patient's age and the severity and timing of the bleeding.

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There are tons of reasons. Here are a few:
1. Endometriosis
2. Polycystic Kidney Disease
3. Trophoblastic Disease
4. If you are pregnant, you could be having a missed abortion or incomplete abortion. You can also be having a placenta previa or abruptio placentae.
5. If you just gave birth, it is normal to bleed for at least 4 days as long as it is does not saturate at least 2-3 pads per day. Twenty days is definitely abnormal. You might be having a Disseminated Intravascular Coagulation and must be seen right away.
6. Your follicle stimulating hormone is not regulated well. Exercise might help but a visit to the endocrinologist would be the best.
7. If you are on Depo-Povera or recently started a new method of birth control, then you are in at most risk of prolonged bleeding. Consult your nurse who advised you about the birth control.
8. Another cause- cervical cancer. Lastly, any kind of bleeding can be correlated to cancer. Do not be scared to go to the doctor.
GO now ASAP.

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