Cervical polyps are typically removed only if they are large, causing irregular bleeding, or if there is an abnormal Pap smear or a persistently positive HPV (human papillomavirus) test.

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Irregular bleeding can also be the result of endometrial polyps, overgrowths in the lining of the uterus, and can even be a sign of pre-cancer or cancer of the uterus.

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The other very important cause of irregular bleeding is pregnancy, and if a different method of contraception is not being used it is also essential to do a pregnancy test.

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While oral contraceptives have a good safety record (and Barr Laboratories' trial of 1, 400 women showed no evidence that Seasonale is riskier than conventional contraceptive pills, except for a higher incidence of irregular bleeding in the first few months of use), Dr Hitchcock is keen to see women exercise caution when it comes to prolonged use of anything containing sex hormones.

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None of these things are caused by being on the pill, but because the pill is an excellent treatment for irregular cycles the abnormal bleeding becomes apparent only once the pill is stopped.

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