A False Period: What Is It and Why Does It Appear?

A false period is bleeding that often alarms a mother who's at the beginning of her pregnancy. However, in most cases, there's nothing to fear, as it's a normal process. Learn more here!
A False Period: What Is It and Why Does It Appear?

Written by Edith Sánchez

Last update: 27 May, 2022

A false period is menstrual-like bleeding that occurs during the first weeks of pregnancy. It’s known as “false” because it doesn’t actually correspond to a period as such. In fact, it’s usually implantation bleeding.

Many pregnant women go to emergency centers when they detect this type of bleeding. However, this is the right thing to do. That’s because, although in most cases, the false period is normal, this symptom can also be a sign that something’s wrong.

A false period is also known as “false menstruation” or “metrorrhagia.” If a woman doesn’t know she’s pregnant, she’ll most likely mistake the bleeding for a normal period. She may then feel a little puzzled when the dates of the onset of pregnancy and the last supposed menstruation don’t match.

What is the cause of the false period?

A woman sitting on the edge of her bed with abdominal pain.
The bleeding is known as a false period that usually occurs when the embryo implants in the uterus.

Most commonly, the false period corresponds to implantation bleeding. The process begins on the sixth day after fertilization. This is the time when the embryo implants in the outer layer of the uterus, or endometrium.

Implantation lasts between two and three days. During this time, the fertilized egg produces a substance that erodes the cells of the endometrium. This way, the embryo gradually embeds itself in the outer layer of the uterus.

While this is happening, some blood vessels can break, and this causes false menstruation. Sometimes, the cause of the bleeding may be something else, as we’ll discuss below.

Vaginal or cervical injury

In the first trimester of pregnancy, these areas are more sensitive and irritated. Therefore, it’s easier for them to bleed from a gynecological examination, sexual intercourse, or intense physical activity.

A false period: A threat of miscarriage

If there’s only a threat of miscarriage, the cervix remains closed. When a miscarriage is in progress, in addition to bleeding, the cervix opens and there are other associated symptoms such as lower abdominal pain.

Ectopic pregnancy

Ectopic or extrauterine pregnancy also causes a false period. This name refers to a condition in which the embryo implants outside of the uterus. Most commonly it does so in the fallopian tubes, but it can also do so in the abdominal cavity, the cervix, or an ovary.

In this condition, there’s insufficient hormone production, and this causes the desquamation of the endometrium. This, in turn, could give rise to bleeding that appears as a slight spotting along with other symptoms such as nausea, vomiting, etc.

You may also be interested in: Irregular vaginal bleeding – why it happens

Molar pregnancy

Molar pregnancy or hydatidiform mole is an unusual tumor that forms in the uterus at the beginning of a pregnancy. This is the result of abnormal fertilization and results in an abnormal fetus. One of the symptoms of this condition is bleeding during the first trimester of pregnancy.

The symptoms of false menstruation are very similar to those of regular menstruation. Under typical conditions, it occurs on day 12 after ovulation, so it coincides with the date of menstruation.

However, the flow is less abundant, lighter in color, and has no clots, i.e. it has a more liquid texture. It lasts a maximum of three days and is accompanied by headache, tiredness, pain in the abdomen, breast tenderness, and irritability.

Most commonly, symptoms such as the following are present after the false period:

  • Pain in the abdomen and cramping
  • Diarrhea or constipation
  • Heartburn
  • Swelling in the breasts
  • Frequent urination
  • Nausea and vomiting, especially in the morning
  • Refusal of certain foods
  • Intolerance to some smells
  • Cravings
  • Drowsiness

When to see a doctor

If bleeding occurs in early pregnancy, there’s no reason for alarm. Most often, it’s a false period and corresponds to implantation bleeding, which is completely normal.

However, there are also other causes of bleeding. As it’s not possible to establish the cause yourself, the best thing to do is to consult a doctor whenever this happens. This is the way to corroborate that everything’s fine and that there’s no risk.

Diagnostic tests for a false period

To formulate the diagnosis, the doctor first conducts an interview. They’ll inquire about your general health and family history. At the same time, they’ll gather information about the date of onset and the characteristics of the bleeding.

Then, they’ll perform a physical examination and may perform a rectovaginal examination to detect any possible abnormalities. They may also perform a speculum exam and order one or more of the following tests:

  • Blood tests
  • Thyroid function test and hormone levels
  • Urine test
  • Ultrasound of the abdomen and pelvis
  • CT scan or MRI
  • Papanicolaou test
  • Biopsy

Treatments available

A woman who's looing upset as she talks with her doctor.
The physician will determine the most appropriate treatment for the cause of a false period.

The treatment of false menstruation will depend on the cause that produces it. When it’s implantation bleeding, as is the case most of the time, no treatment is necessary. The bleeding will stop on its own and won’t cause any consequences.

If the false period is a sign of a threatened miscarriage, the doctor will order strict rest until the bleeding stops. If it’s a miscarriage in progress, a decision must be made between allowing it to complete spontaneously, speeding up the process with medication, or performing a dilatation and aspiration curettage.

However, if the diagnosis of ectopic pregnancy is confirmed, surgery is required. This should be done as soon as possible. When the cause of the false period is something else, the doctor will indicate the steps to be taken.

Lifestyle and recommendations

False menstruation as such doesn’t imply the acquisition of new habits. You should practice the same care you would practice with any pregnancy unless otherwise indicated by the doctor. In general, a healthy lifestyle with a balanced diet, physical activity adjusted to gestation, and peace of mind are adequate.

A threatened miscarriage requires a lot of rest, peace of mind, and continuous medical follow-up. It’s important to follow the indications strictly. If the miscarriage occurs, it’s possible to experience multiple emotions. Consultation with a psychologist is highly recommended.

After overcoming the treatment of an ectopic pregnancy, psychological assistance may be required. It’s also very important to have a supportive social and emotional network. The prospect of a future pregnancy will depend on each case.

If you have a false period, consult your doctor

When faced with a false period, the best thing to do is to consult your doctor to determine if it’s really false menstruation or if there’s some other problem. The doctor will offer guidelines and these should be followed precisely.

It’s common for a false period to occur because of implantation bleeding. This won’t affect the development of the pregnancy and doesn’t constitute an anomaly. If the cause is something else, the most important thing is to be guided by the doctor to determine what should be done.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Galaz-Montoya, C. I., Razo-Aguilera, G., Grether-González, P., & Aguinaga-Ríos, M. (2015). Aspectos genéticos de la mola hidatidiforme. Perinatología y reproducción humana, 29(3), 113-117.
  • Valdez-Morales, F. J., Vital-Reyes, V. S., Hinojosa-Cruz, J. C., & Cerbón, M. (2014). Funcionalidad y cambios endometriales asociados con la inducción de ovulación con citrato de clomifeno y FSH recombinante en mujeres con infertilidad. Ginecología y Obstetricia de México, 82(02), 143-153.
  • Lage, P. R., Suárez, A. V., & Rodríguez, M. A. (2012). Metrorragia de primer trimestre. Cuadernos de atención primaria, 18(4), 332.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.