Online Pregnancy Test: What Is It and How Does It Work?

The online pregnancy test is based on the manifestation of early symptoms that could suggest the possibility of a pregnancy. Learn all about this test and its reliability here.
Online Pregnancy Test: What Is It and How Does It Work?
Maryel Alvarado Nieto

Written and verified by the doctor Maryel Alvarado Nieto.

Last update: 06 April, 2023

In the information age in which we live, it’s common to find web pages that diagnose certain diseases. Similarly, there are online sites that offer questionnaires that can be useful to know if there’s a possibility of presenting any condition: such is the case of the online pregnancy test.

These tools are usually free and are based on the recognition of early symptoms that appear frequently in pregnant women. Therefore, they’re not considered reliable detection methods and there is no scientific backing to support them.

What is an online pregnancy test like?

Several websites offer questionnaires that seek to recognize the classic symptoms of pregnancy in its early stages. How they collect the information varies, but they generally have selection questions, in which the woman has the possibility of choosing the option that most closely resembles what she is feeling.

In this way, the questionnaire serves as a checklist of the symptoms that suggest that she is pregnant. However, these symptoms do not appear in all women, nor all pregnancies. Therefore, their presence or absence does not confirm or rule out the existence of a pregnancy.

We think you may also enjoy reading this article: Possible Psychological and Emotional Changes in Pregnancy

The reliability of the online test

The information handled by this type of site has a statistical basis. The symptomatology that it investigates is part of a group of clinical manifestations that are common in many pregnant women. This statistical analysis allows a presumptive detection in the early stages.

This implies that the results obtained from the online pregnancy test are only indicative. Therefore, the recommendation is that, despite the response offered by this type of questionnaire, the woman should have a laboratory test or an ultrasound to provide certainty.

Ecografía de embarazo.
A pregnancy ultrasound or urine/blood test are still the ideal methods to confirm a pregnancy.

What symptoms are used in the online pregnancy test?

This type of page determines the possibility of being pregnant by reviewing a set of symptoms described in the literature as early signs of pregnancy. The more symptoms a woman has, the greater the probability of being pregnant.


The main reason for suspecting pregnancy lies in the absence of a period, a situation known as amenorrhea. It’s of vital importance that the evaluation of the disappearance of the period is done in women who have regular menstrual cycles and who have not used any type of hormonal contraceptive recently.

Likewise, the number of days of delay should also be considered, since some stressful situations affect the menstrual cycle. In addition, a history of uterine curettage can lead to the suspension of menstruation, since it leads to a delay in the proliferation of the endometrium.

On the other hand, the presence of bleeding is not enough to rule out the existence of pregnancy. This is because, in the first weeks, a light discharge may appear, which could be mistaken for menstruation. This bleeding is the result of the implantation process of the product of conception in the uterus.

The first changes expected in pregnancy

Some subtle manifestations may go unnoticed, but whose presence is considered presumptive of pregnancy. Among them is a change in the color of the genitals, which change from a pinkish hue to become a little more purplish. This finding is known as Chadwick’s sign.

A pregnant woman may also experience an increased tendency to be irritable, tired, and drowsy. But these changes are sometimes difficult to recognize by the patient herself and a review of them may be unsuccessful.

Despite this, they are frequently addressed in the online pregnancy test.

The above difficulty further reduces the reliability of this type of questionnaire. A negative response to a manifestation that is actually present may give a false result in a woman who is pregnant.

Often the questionnaires available on various sites address a group of symptoms that are considered by the general population to be characteristic of a pregnant woman. Particularly during the first weeks of gestation.

Among these manifestations are the following:

  • The presence of vertigo and headaches.
  • Increased breast tenderness.
  • Nausea and vomiting, usually in the morning.
  • Rejection of certain smells or flavors, which did not use to produce this displeasure before.
  • Attraction to some specific foods (a symptom popularly known as a craving).
  • An increased need to urinate. Urination is more frequent, but usually in small amounts.

This list should be reviewed with caution, since although they are popular symptoms, their absence does not rule out pregnancy. Their presence doesn’t confirm it either.

This is because none of them is exclusive to pregnancy. However, they do tend to be present in the early stages of pregnancy for many women.

Náuseas matutinas por embarazo son parte del cuestionario de embarazo online.
First-trimester morning sickness is very common during pregnancy. That’s why online tests ask about this symptom.

To trust or not to trust it: The weakness of the online pregnancy test

An important issue that none of these pregnancy tests consider is the variability of symptoms, as they assume them to be common. And the reality is that each of them differs from one another in terms of their frequency of occurrence.

Even so, most of these sites warn that their results are not accurate.

On the other hand, they also fail to take into account some characteristics that are specific to each woman. These tend to affect the early manifestations of gestation, making it a little more difficult to interpret the results that an online pregnancy test yields.

Among these characteristics that increase the weakness of the online test are the following:

  • The age of the woman
  • Previous pregnancies
  • Physical and nutritional status
  • Regularity of menstrual cycles

The usefulness of the online pregnancy test

Despite the limitations, these tools do have the ability to help those women with initial doubts. It allows them to review the most common early manifestations of pregnancy and provides them with some enlightening information about these symptoms.

The caveat of these types of questionnaires lies in the need to confirm their results later. Whether through the detection of human chorionic gonadotrophin in the blood or by performing an obstetric ultrasound, it is pertinent to seek confirmation. Similarly, an online pregnancy test should not replace prenatal assessment.

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.

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