Wellbeing-Guide: How To Know if It's Implantation Bleeding or Your Period

How To Know if It's Implantation Bleeding or Your Period

By Wendy Wisner | Posted on 2024-06-29 | health.com

Drazen Zigic / Getty Images

Implantation bleeding is when you spot or have light bleeding around the time an egg implants into the uterine wall during pregnancy. Studies have found that about 25% of people experience implantation bleeding.

Experiencing spotting or light bleeding can be shocking or concerning. If you are trying to conceive or think you may be pregnant, you might want to know if what you are experiencing is implantation bleeding or if you may be having your period.

Implantation bleeding differs from menstruation in several ways, including the timing, the type of bleeding that occurs, and how long the bleeding lasts.

Key Differences Between Implantation Bleeding and Periods

While both implantation and menstruation involve vaginal bleeding, there are several significant differences. Knowing these differences can help you understand what you may be experiencing.

Timing

Implantation bleeding typically occurs around the time that a fertilized egg implants itself into your uterus. This usually occurs about 6-12 days after you conceive. The light spotting associated with implantation can occur for up to 1-2 weeks after conception. As such, the timing of implantation bleeding can occur during the week before your expected period or even around the time of your expected period.

The timing of when you get your period can vary from one person to another and from month to month. Menstrual periods usually occur about two full weeks, or 14 days, after you ovulate. The average length of a menstrual cycle is 28 days, with ovulation occurring around day 14. However, if ovulation occurs earlier or later, you will have a longer or shorter cycle. Average menstrual cycles can last 21-35 days.

Duration

Implantation bleeding can occur on and off during and after implantation. It tends to be fairly brief, usually lasting a few hours or one day. However, it can last as long as three days.

Bleeding during menstruation tends to last longer. The average period lasts 4-6 days, but it can last up to eight days.

Amount of Blood

Most people describe implantation spotting as bleeding in very small amounts, such as a few spots on your underwear or a very light period.

Period bleeding tends to be heavier. Although a typical period might start and end with spotting or light bleeding, you will likely experience several days of heavier bleeding. A typical period averages about 30 milliliters (mL) of blood.

During your period, it’s common to fill pads with and need to change tampons frequently. With implantation, you will likely only see blood when you wipe, or you may see a few spots on your underwear, pantyliner, or other small pad.

Appearance of Blood

With implantation spotting, the blood you see tends to be lighter in color than your period blood. Implantation bleeding may look lightish pink and may also look rust-colored or brown (this indicates older blood that was slow to flow out).

Period blood tends to be a darker red or even bright red. It’s normal to see clots during your period, but clotting is not typical for implantation bleeding.

How To Identify Symptoms of Implantation Bleeding

You can usually identify implantation bleeding by the symptoms and timing of your bleeding. Here’s what to know:

Implantation bleeding tends to occur about 1-2 weeks after ovulation.
It typically occurs before your expected period, though it might occur around the time of your period.
It is much lighter in flow than a typical period. The bleeding isn’t enough to necessitate a tampon or large sanitary pad.
The blood may look lighter pink or even brown.

Implantation bleeding is associated with early pregnancy. Therefore, you may also experience some of the signs of early pregnancy, such as:

Sore breasts that may be larger than usual
Sore or tender nipples
Fatigue
Headaches
Nausea
Vomiting
Food cravings or aversions
Increased moodiness
More frequent urination

Other Causes of Spotting

Unusual spotting or bleeding is fairly common, and most people will experience it at one point or another during their reproductive years. Bleeding or spotting is also common in early pregnancy. In most cases, it’s nothing to be concerned about. However, always contact a healthcare provider if you notice new spotting or bleeding.

Common causes of non-period bleeding include:

Medications: For example, hormonal birth control or hormone therapy
Ovulation irregularities: For example, due to hormone-related conditions like polycystic ovary syndrome (PCOS) or thyroid dysfunction
Vaginal atrophy: Thinning and drying of vaginal walls (usually leading up to menopause or during menopause)
Vaginal erosion: Also called cervical ectropion, when cervical cells grow outside the cervix (usually leading up to menopause or during menopause)
Benign cervical polyps: Non-cancerous tissue growths in the cervix
Benign cervical and uterine fibroids: Non-cancerous tissue and muscle growths in the cervix or uterus
Vaginal infections: For example, sexually transmitted infections (STIs)
Endometriosis: When tissue similar to the lining of the uterus (endometrium) grows outside the uterus
Cervical cancer: Less common, but important to rule out

During early pregnancy, implantation bleeding isn’t the only possible cause of bleeding. You may also bleed in early pregnancy because of hormonal changes that cause increased blood vessel development in your vagina or cervical region.

For example, you might notice light bleeding or spotting after sexual intercourse, or you might notice bleeding after a pelvic exam or pap smear. If your healthcare provider tells you that this is due to hormonal changes during pregnancy, there is nothing to worry about.

However, sometimes bleeding in early pregnancy is a sign of pregnancy loss (miscarriage) or other pregnancy concerns. Causes of vaginal bleeding in the early months of pregnancy can include:

Subchorionic hematoma: Blood pools between the embryo’s amniotic wall and your uterine wall, which can cause complications (rare)
Ectopic pregnancy: The embryo develops inside of your fallopian tube rather than your uterus and is considered a medical emergency
Gestational trophoblastic disease: Abnormal cells grow outside the uterus during pregnancy, which is usually a benign condition

Tracking Your Cycle

Identifying implantation bleeding and differentiating it from your period is all about timing. Implantation bleeding typically occurs about 1-2 weeks after ovulation, but not everyone knows when they ovulated. Tracking your cycle can be helpful.

The Calendar Method

Using the calendar method is one way to figure out when you may have conceived. Ovulation typically occurs about 14 days before your period. Therefore, you can calculate the typical length of your period and do the math backward. For example:

If your periods are usually about 28 days, you likely ovulate around day 14.
If your periods are shorter (e.g., 21 days), you likely ovulate around day 7.
If your periods are closer to 35 days, you likely ovulate around day 21.

Could You Be Pregnant?

If you had intercourse around the time you ovulated and then spot 1-2 weeks later, it’s possible that you are pregnant and what you are seeing is implantation bleeding.

Other Signs of Ovulation

Most people combine the calendar method with other signs of ovulation to determine when they may have conceived and whether what they are seeing is implantation bleeding. Other signs of ovulation include:

Increased cervical fluid that may resemble egg whites
Increased energy
Increased sex drive
One-sided cramping
Spotting
Breast tenderness

If you have sex when you show these fertile signs, and these fertile signs occur around when you expect ovulation, you may be pregnant. If so, your spotting or bleeding 1-2 weeks later may be a sign of pregnancy.

When To Take a Pregnancy Test

Take a pregnancy test if you experience signs of implantation bleeding and think you may be pregnant. However, remember that implantation bleeding can occur about a week or so after you conceive, which is usually before your expected period. At-home pregnancy tests may not be able to tell you whether you are pregnant or not because most tests work most accurately if you test around the time of your expected period.

If your at-home pregnancy tests give a negative result and you aren’t expecting your period yet, you can always wait and take a pregnancy test a few days later. Alternatively, you can visit a healthcare provider to give you a pregnancy blood test. Your provider can also discuss your symptoms of implantation bleeding.

A Quick Review

Implantation bleeding occurs when a fertilized egg implants itself into the uterus. This bleeding is usually light and more like spotting. It typically happens about one week after conception, though you may experience light bleeding up 1-2 weeks after conception.

Implantation bleeding tends to occur before an expected period and is much lighter in flow than an average period. Although implantation bleeding is common, it’s important to discuss any new or unusual bleeding with your healthcare provider.

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