What Causes Abnormal Bleeding Between Periods?

By on August 13, 2020

abnormal bleeding

Bleeding between periods can be a worrisome symptom, but there are many causes for irregular vaginal bleeding, and not all are cause for serious concern. It’s important to see your doctor whether you have spotting or heavier bleeding outside of your regular period, but it’s also helpful to know what the causes could potentially be before your appointment.  

Hormonal Imbalance 

The two main hormones which regulate the menstrual cycle are estrogen and progesterone. An imbalance of these two hormones can cause irregular bleeding. Hormonal imbalances can be caused by issues with your ovaries or thyroid gland. In addition, it’s common to see irregular bleeding as your hormones adjust to new types of birth control or you’ve recently stopped using birth control. This includes birth control pills, patches, implants, or intrauterine devices.  

Uterine Fibroids  

Uterine fibroids are noncancerous growths within the uterus, which can cause bleeding or spotting. They may also be known as “leiomyomas,” “myomas,” or “fibromas.” Their cause is generally unknown, but they occur more typically in women who have not given birth. While fibroids are benign overall, they can cause pain or difficulty conceiving as well as irregular bleeding. 


An infection of the reproductive organs can cause vaginal bleeding between your regular periods as well as inflammation. There are several common causes of infection, which include: 

Complications During Pregnancy  

Complications with a pregnancy can commonly cause spotting. While not all cases of spotting during pregnancy are cause for concern, bleeding can be a sign of miscarriage or ectopic pregnancy, which is when a fertilized egg implants itself into the fallopian tube.  

Rare Causes for Abnormal Bleeding 

There are a number of rarer causes for abnormal vaginal bleeding. The first is certain types of cancer, including cervical, vaginal, uterine, or ovarian. While serious, these cancers are relatively rare.  

Some other rare causes of irregular bleeding are:  

  • Insertion of an object into the vagina 
  • Excessive stress 
  • Thyroid disorders 
  • Diabetes 
  • Significant changes in weight (gain or loss) 

When to See Your Doctor 

It’s generally best to see a doctor whenever you’re experiencing abnormal bleeding, even if you suspect the cause is less serious. Typically, a cycle lasts between 21-35 days, with the period happening for about 2-7 days. It can be helpful to track your cycle to understand what’s normal for you and what isn’t, so you know when to call your OB/GYN. 

Schedule an Appointment 

To schedule an appointment with a qualified OB/GYN, call Maternal Fetal Medicine Associates in New York City at (212) 235-1335 or request an appointment online 

Maternal Fetal Medicine blogs are intended for educational purposes only and do not replace certified professional care. Medical conditions vary and change frequently. Please ask your doctor any questions you may have regarding your condition to receive a proper diagnosis or risk analysis. Thank you!

©MaternalFetalMedicineAssociates 2024 | Site Map | Privacy Policy | Cookie Policy | Accessibility Statement