Sudden and Unexplained Periods – Causes and Warning Signs

On average, women have a period every 28 days – this is known as the menstrual cycle. Sometimes it is shorter cycle, as short as 22 days, while at other times it is longer, up to 32 days. Even in this case it is considered to norm as long as the cycle is stable, a woman ovulates prior to menstruation and the flow is within an acceptable quantity without symptoms like severe period pain. There are instances when a woman may experience vaginal bleeding at a time when she was not expecting her periods. This bleed is not always a period meaning that it is not a result of the inner lining of the uterine wall shedding and being expelled. It is however always advisable to have any abnormal vaginal bleeding assessed by a doctor because at times it may be the sign of serious and even life threatening gynecological disorders.

Causes of Unusual Periods

There are a number of possible reasons for sudden and unexplained periods. Most of the time bleeding is not due to periods but is instead termed intermenstrual bleeding. There are cases where some women have their periods more often but this is marked by a shorter menstrual cycle and does not come about suddenly and unexpectedly. Some of the more common causes of sudden and unexplained periods for particular age groups includes :

  • Trauma to the vagina or cervix may arise after sexual activity, even a day or two afterwards. It is important to exclude pregnancy as a possible cause as well.
  • Implantation bleed also occurs after sexual activity and is a consequence of pregnancy. It can occur anywhere between 6 to 12 days after fertilization.
  • Miscarriage or spontaneous abortion where the pregnancy ends due to the death of the fetus. A threatened abortion may also present with bleeding but with proper treatment the pregnancy may still be viable.
  • Sexually transmitted infections (STIs) including gonorrhea, syphilis and chlamydia.

The common causes mentioned above are mainly related to pregnancy. In some cases women are not aware of the pregnancy and only discover it when there is abnormal vaginal bleeding. Other causes of sudden or unexpected vaginal bleeding includes :

  • Ectopic pregnancy is where the fertilized egg is growing within fallopian tube and not in the uterus. The pregnancy is not viable and emergency medical attention is needed to prevent harm to the mother.
  • Intra-uterine device (IUD) may cause occasional spotting.
  • Stopping birth control pills.
  • Using emergency contraceptives like the “morning after” pill.
  • Blood thinners (anticoagulants)
  • Psychological stress which can upset the menstrual cycle.
  • Abnormal hormonal changes due to medication, illness or any other factor.
  • Perimenopause – the stage before menopause marked by irregular menstruation and heavy periods.
  • Polyps in the uterus
  • Uterine fibroids
  • Genital warts
  • Cancer of the cervix, uterus or fallopian tube.

Warning Signs

 There are certain instances when sudden and unexplained periods are a sign of a serious and dangerous condition. Immediate medical attention is required in these cases. There are certain warning signs that may also be present which should warrant the need for a trip to the emergency room. This includes :

  • Intolerable abdominal and pelvic pain
  • Dizziness
  • Fainting spells
  • Paleness of the skin
  • Bluish discoloration of the skin, especially the lips
  • Cold and clammy skin
  • Profuse vaginal bleeding that cannot be held back even with several sanitary pads.

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