Positive Pregnancy Test After Period: Possible Explanations

If you obtain a positive outcome on a pregnancy test after your menstrual cycle, it is most likely attributed to the following possible explanations:

  • The bleeding was not a period but rather normal early pregnancy bleeding. 
  • The test result was a false positive due to an early miscarriage, chemical pregnancy, medications, misuse of the test, etc.
  • You have an ectopic or molar pregnancy.
  • The blood is due to infection or internal injury.
  • The test was taken weeks after the period, and you became pregnant during the subsequent fertility window.
  • You misread the results.

While you will not have a period if you are pregnant, it is possible to receive a positive pregnancy test following an assumed period. 

The bleeding you experienced was not likely a period, and the pregnancy may or not be viable, depending on the cause.

Either take another home test in a few days or see your healthcare provider to have a blood test performed.

Contact your doctor immediately if you have any concerns.

If you want to take a pregnancy test while bleeding in any form is occurring, the blood will not affect the results.

Bleeding After a Positive Pregnancy Test

You will not have a period if you are pregnant. It is easy to mistake bleeding in early pregnancy for a period, especially if your periods are on the lighter side.

Allo Health explains how to tell the two apart:

  • The color of the blood: Blood during a period tends to be darker, while blood during pregnancy can be pink or light brown.
  • The amount of blood: Bleeding during pregnancy is typically lighter than a period and does not fill up a pad.
  • The duration of the bleeding: A period typically lasts between three and five days. Bleeding during pregnancy usually lasts for a shorter period of time.
  • Pain: Women may experience cramping during both periods and during bleeding during pregnancy. However, the pain during pregnancy is generally milder.

Regardless of the quantity and type of blood, it’s best to let your doctor know right away.

Below we explain some of the most common reasons for bleeding. 

1. Chemical Pregnancy

A chemical pregnancy is an early miscarriage that occurs within the first few weeks of pregnancy, often before a woman realizes she’s pregnant. 

A chemical pregnancy happens when a fertilized egg fails to develop properly after implantation.

This can lead to a drop in the pregnancy hormone hCG, causing the uterine lining to shed and resulting in bleeding similar to a period. 

Chemical pregnancies are common and usually not indicative of underlying fertility issues.

2. Implantation Bleeding

Implantation bleeding occurs when the fertilized egg implants into the uterine lining.

This type of bleeding is often accompanied by small menstrual-like cramps. 

3. Miscarriage

Bleeding due to a miscarriage can be light or heavy depending on how far into the pregnancy it occurs.

Miscarriage bleeding will usually be accompanied by other symptoms such as severe cramping.

If it’s late into the first trimester and the placenta has begun developing, there will often be clots in the blood as these are expelled through the vagina.

4. Normal Pregnancy Spotting

A lot happens in the body as it prepares for and accepts a newly fertilized egg.

With the uterus beginning to expand, a thick uterine lining developing, a placenta forming, and a baby growing, there’s a lot that can cause you to release bits of blood into the vagina to be expelled.

This type of bleeding is usually streaky and light in color and does not last long. 

5. Ectopic or Molar Pregnancy

Bleeding from an ectopic pregnancy is almost always accompanied by other symptoms such as abdominal and pelvic pain, dizziness, nausea, vomiting, or rectal pressure.

This bleeding will typically be on the heavier side. It’s important to seek medical help if you are having any of these symptoms while pregnant. 

Symptoms and bleeding resulting from a molar pregnancy are similar to that of an ectopic.

However, bleeding may be paired with the vaginal passing of small grape-like cysts. 

6. Infection

Bleeding caused by infections is usually light to moderate in flow. Other symptoms of vaginal, urinary, or sexually transmitted infections will persist as well.

This includes but is not limited to frequent and/or painful urination, inflammation of the urinary tract, inflammation of the reproductive organs, and sour odor. 

7. Injury From Internal Exam or Intercourse

During pregnancy, the cervix becomes more tender, sensitive, and prone to bleeding.

In addition, there is an increase in blood flow to the area as your body prepares to grow life.

The insertion of any item can disrupt a number of components and cause light to moderate bleeding.

This bleeding is usually light in color and stops after a short period of time.

8. Problems With the Placenta

Complications with the placenta such as placenta previa and placental abruption can cause bleeding in the later stages of pregnancy.

Placenta previa is when the placenta is near or covers the cervical opening.

Placental abruption occurs when the placenta dislodges itself from the uterine wall.

Placenta abruption can result in heavy dark bleeding from the vagina and requires immediate medical attention.

9. Subchorionic Hematoma

Subchorionic hematomas are when the membranes surrounding the embryo begin to bleed.

This can result in light to moderate bleeding from the vagina.

Typically, subchorionic hematomas resolve on their own, but they should still be monitored by a doctor. 

10. Cervical Polyps

Cervical polyps are benign growths on the cervix that can bleed in pregnancy.

They are caused by elevated estrogen levels. This bleeding is typically harmless, spotty, and light in color.

When To Be Concerned About Bleeding in Early Pregnancy

Bleeding in early pregnancy can be a normal occurrence, but the causes behind it vary drastically in severity and intervention.

For this reason, bleeding at any stage of pregnancy should be reported to your doctor right away.

To prevent unnecessary stress, remember that spotting or light bleeding is usually not severe. This type of bleeding typically requires little to no intervention.

Notify your doctor or go to the hospital right away if you have:

  • Heavy bleeding.
  • Bleeding with bright red blood and clots.
  • Bleeding accompanied by pain and/or cramps.
  • Bleeding accompanied by dizziness.
  • Pain in your pelvis or lower abdomen.

Why Periods Stop During Pregnancy

In the weeks prior to a period, your body has prepared an ideal environment for a baby to grow.

During ovulation, the body releases the most matured egg from the ovary through the fallopian tube into the uterus.

If the egg is fertilized on this journey, it implants into the uterine lining.

Since a period is the shedding of the uterine lining without a fertilized egg, you will not have a period when you are pregnant.

Bleeding vs. Spotting

While any amount of blood during pregnancy triggers worry, it’s important to understand the difference between bleeding and spotting. 

Spotting is when you are expelling faint traces of vaginal blood. This usually takes on a light red, pink, or brown color and does not require you to wear a pad.

On the other hand, bleeding is when there are significant amounts of dark red blood or blood clots. This type of bleeding typically requires the use of a pad.

Regardless of how much or little you’re bleeding, you should contact your doctor right away.

Bleeding in early pregnancy can be a normal occurrence, but it’s always best to be on the safe side. 

What Is a False Positive Pregnancy Test?

False positive pregnancy tests are rare, but they do occur. Pregnancy tests pick up on an early pregnancy hormone called hCG.

When that hormone is present in detectable amounts, regardless of the reason, the pregnancy test will display a positive result, even if you are not pregnant with a viable embryo. 

Causes of a False Positive Pregnancy Test

There are many reasons you may receive a false positive. The most common are explained below.

Evaporation Lines

An evaporation line is a faint and colorless second line that shows up on pregnancy tests.

Evaporation lines are caused by the urine evaporating from the stick, and they can mistakenly be read as a positive result.

The best way to prevent evaporation lines is to follow the directions as precisely as possible, especially when it comes to timing. 

Chemical Pregnancy

A chemical pregnancy is when a fertilized egg, otherwise known as an embryo, is unable to implant in the uterus early on.

This process of fertilization causes the body to ramp up hCG production, but with the inability to implant, the egg dissolves, and hCG levels return to normal.

This can cause a false positive pregnancy test.

Miscarriage or Abortion

Upon conception, hCG levels rise in the body to prepare the uterus for the growth that’s about to occur.

These levels dramatically increase until around weeks eight to 11 when they start to fade, leaving estrogen and progesterone to continue doing their jobs.

It takes up to six weeks after pregnancy ends for hCG levels to return to their normal state. 

So, if you’ve recently had an abortion or a miscarriage, your body may still have elevated levels of hCG. This could cause a false positive.

Ectopic Pregnancy

An ectopic pregnancy occurs when a fertilized egg implants itself outside of the uterus, typically in the fallopian tube.

This is a severe medical emergency since the pregnancy is non-viable and in a dangerous location.

If you believe you may have an ectopic pregnancy, please consult a doctor immediately.

Despite that it is implanted in the wrong location, the egg will still trigger the production of hCG, resulting in a positive reading on a pregnancy test. 

Molar Pregnancy 

A molar pregnancy occurs when an egg is abnormally fertilized.

This causes abnormal cyst growth in place of the placenta, which poses a severe risk to maternal health.

There are two types of molar pregnancies: complete and partial. 

In a complete molar pregnancy, the mother’s chromosome contribution is lost, and only the father’s remains. In this instance, no fetal tissue develops. 

In a partial molar pregnancy, the mother’s chromosome contribution remains, but the father contributes two copies.

Most often molar pregnancies occur because more than one sperm fertilizes the egg. While fetal tissue develops, the pregnancy is non-viable. 

Medications

There are some medications that have been known to influence home pregnancy tests.

Those on the list below are only some of the medications that can cause a false positive.

  • Synthetic hCG shots like Novarel, Profasi, Ovidrel, and Pregnyl
  • Antihistamines like Promethazine
  • Methadone
  • Diuretics like Lasix and Diu Screen
  • Antipsychotics like Clozapine and Chlorpromazine
  • Parkinson’s medications like Parlodel
  • Anti-anxiety medications like Valium and Xanax