Most women have a period that lasts four to seven days. A woman's period usually occurs every 28 days, but normal cycles can range from 21 days to 35 days.

Cycle disorders include:

• periods that occur less than 21 days apart or more than 35 days apart
• amenorrhea for three or more cycles
• flow that is much heavier or lighter than usual
• periods that last longer than seven days
• periods accompanied by pain, cramps, nausea, or vomiting
• bleeding between periods, after menopause, or after intercourse

What causes irregular cycles?

There are many causes of abnormal periods, ranging from stress to more serious underlying medical conditions. Some of these include:

• stress 
• birth control pills 
• endometriosis 
• pelvic inflammatory disease
• polycystic ovary syndrome
• premature ovarian failure 
• endometrial cancer or cervical cancer
• medications, such as steroids or anticoagulants 
• medical conditions, such as bleeding disorders, underactive or overactive thyroid gland, or pituitary disorders that affect hormonal balance
• pregnancy-related complications, including miscarriage or ectopic pregnancy

How is irregular periods treated?

Treatment depends on a number of factors, such as:

• the overall picture of your health
• the cause of cycle irregularities
• your obstetric history and future plans for your family planning

Treatment may include the following:

• medication
• surgery 

When should you contact the doctor?

Contact a Gynecologist if you have any of the following symptoms:

• severe pain during or between periods
• unusually heavy bleeding 
• abnormal or foul-smelling vaginal discharge
• high fever
• period lasting more than seven days
• vaginal bleeding between periods or after menopause
• periods that become very irregular compared to your usual cycles
• nausea or vomiting during your period
• You should also see a doctor if you think you may be pregnant.