Ovulation

• Ovulation is unnoticeable for most women. Some women, however, notice light spotting for a day or two after ovulation. This type of spotting before the period is generally a normal byproduct of ovulation for these women.
  
  

Birth Control

• Spotting is one of the most common side effects of most hormonal birth control options, including birth control pills, hormonal IUDS and the birth control shot, patch and implant. This side effect often subsides after a few months. Women sometimes also experience spotting after they stop using a particular hormonal birth control method.
  
  

Pregnancy

• Many women experience spotting in the first few months of a normal pregnancy, so spotting before an expected period may be a sign that you are pregnant. Spotting can also, however, be a symptom of an ectopic pregnancy, a condition that can be life-threatening if not treated early.
  
  

Miscarriage

• Spotting before an expected period is sometimes the sign of an impending miscarriage. Since you may not suspect that you are pregnant until you miss your period, it is possible to experience miscarriage-related spotting without even realizing that you've become pregnant.
  
  

Hormonal Imbalance

• Spotting can also be the result of hormonal imbalances other than those caused by pregnancy or birth control. For instance, your body may be producing too much estrogen or not enough progesterone, possibly due to a thyroid problem or from taking certain medications.
  
  

Serious Conditions

• Spotting before your period is sometimes a sign of an underlying condition such as uterine fibroids or polyps, ovarian cysts or cervical or uterine cancer. While rare, these conditions can be serious and may require treatment.
  
  

When to See Your Doctor

• You should consult your doctor if you experience any spotting between your periods. While your spotting may be perfectly normal, it's important to rule out pregnancy or any underlying conditions. If you experience very heavy bleeding between periods, contact your doctor immediately.