What Is Implantation Bleeding?
Implantation bleeding is light vaginal bleeding or spotting when a fertilized egg implants into the lining of the uterus (endometrium). It is a very early sign of pregnancy.
Each month an egg is released from the ovary and travels through the fallopian tube. When the egg becomes fertilized by sperm, it starts to divide into multiple cells. These cells travel to the uterus and implant in the endometrium. The endometrium has many blood vessels, so it is possible for bleeding to occur as the egg attaches to the lining.
When Does Implantation Bleeding Happen?
Implantation bleeding occurs about 10-14 days after the egg is fertilized. Unfortunately, that’s about the time your period starts. Implantation bleeding is noticeably different from your period. However, it may be hard to tell them apart when they occur so close together.
Differences Between Implantation Bleeding and Your Period
Implantation and period bleeding may appear similar, but some key differences exist:
- Flow: Implantation bleeding is light. It is often only noticeable when you wipe after using the bathroom. Menstrual bleeding is heavier than implantation bleeding and may require a few pad or tampon changes each day.
- Color: The color of implantation bleeding is usually light pink or rust. Menstrual bleeding is usually bright or dark red.
- Consistency: Menstrual bleeding can be thick in consistency. Implantation bleeding is typically much lighter, more like spotting.
Other Causes of Bleeding
Some other possible causes of bleeding include:
- Pelvic inflammatory disease (PID)
- Noncancerous growths (uterine polyps, fibroids, cervical polyps)
- Oral contraceptives (breakthrough bleeding)
- Thyroid disease (irregular periods)
- Endometrial cancer
When to See a Healthcare Provider
Implantation bleeding is not serious and does not require medical care. However, it is important to alert your healthcare provider any time you experience bleeding when you are pregnant (or suspect you might be). Your provider will help you determine if your bleeding is concerning and requires medical care.
If you experience any of the following symptoms, it’s best to contact a healthcare provider:
- Menstrual bleeding that soaks through one or more tampons or pads every hour
- Menstrual bleeding that lasts more than seven days
- Menstrual cycles that are longer than 35 days or shorter than 21 days
- Bleeding or spotting between periods
- Bleeding after sex
- Pain in the pelvis or abdomen that is not related to your period
Summary
Implantation bleeding is light vaginal bleeding or spotting when a fertilized egg implants into the uterine lining. It often appears as a pink or rust-colored discharge. Implantation bleeding occurs around days 20 to 24 in a 28-day cycle.
Menstrual bleeding during your period is usually heavier and happens on the first day of your cycle. Period bleeding usually appears bright or dark red. To know if you are pregnant, take a pregnancy test about one week after your missed period.
