According to St. John Health System, most women will experience light bleeding (spotting), irregular periods or breakthrough bleeding at least once during their lifetime. Irregular bleeding and spotting between menstrual periods can be caused by a variety of conditions, some relatively harmless while others are quite serious.
WomentoWomen.com points out that most of the time, irregular periods are harmless. Some women regularly experience spotting between periods due to stress, hormone fluctuation, ovulation and use of an IUD (intrauterine device).
It can also be caused by pregnancy complications; injury to the vagina (which can result from intercourse, infection or polyp) or hypothyroidism (under-active thyroid).
Irregular vaginal bleeding can be caused by serious conditions such as miscarriage, uterine cancer, cervical cancer or cancer of the fallopian tubes.
What To Do
If you are experiencing irregular bleeding, first make sure that it is coming from your vagina and not from your urine or rectum. Insert a tampon to confirm that the bleeding is coming from your uterus, cervix or vagina.
When to Call Your Doctor
Contact your doctor immediately if you are experiencing irregular bleeding and you are post-menopausal, pregnant or if you have any additional symptoms (such as fever or pain).
Your doctor will need to thoroughly examine you to rule out physical abnormalities. She will also likely order blood work to check your thyroid function and rule out anemia.