What Are the Different Types of Pregnancy?

Knowing you're pregnant is a blessing, but the first thing a woman needs to know is the type of pregnancy she is having. This will determine in large part whether the pregnancy is viable.
What Are the Different Types of Pregnancy?

Written by Thady Carabaño

Last update: 26 May, 2022

When a woman gets the good news that she’s pregnant, it unleashes a whole whirlwind of emotions, fears, doubts, and hormones. Each medical check-up raises a million questions about whether the pregnancy is developing as it should. However, the first thing the mom-to-be needs to know is what kind of pregnancy it is.
According to the World Health Organization (WHO), pregnancy is the part of the human reproduction process that begins when the fertilized egg is implanted in the wall of the uterus, and ends with the birth.

Each woman’s pregnancy is different. Some are more complicated than others, and even if a woman has two pregnancies, they won’t be the same.

However, did you know that, from a medical standpoint, there are three types of pregnancies? The classification has to do with the implantation of the fertilized egg.

We’ll tell you more in this article.

Types of pregnancy

1. Intrauterine pregnancy

Types of pregnancy: a medical check-up.

This type of pregnancy happens when the fertilized egg is correctly implanted inside the uterus and develops normally.

Intrauterine pregnancy is what most women have. It lasts 40-42 weeks from the first day of the last menstruation, or 38 weeks from when the egg is fertilized.

Once it’s implanted, the placenta grows. The baby will receive all the nutrients it needs to grow via the umbilical cord.

The conditions or factors at play when the woman gets pregnant will determine whether it’s a low risk or high risk pregnancy.

  • Low risk pregnancy

This is the controlled pregnancy of a healthy woman. It occurs in women between 19 and 35 years old. There are no health conditions that could put the mother’s life or the baby’s development at risk.

  • High risk pregnancy

This is when the pregnancy is not controlled. It occurs in women under 18 (underage pregnancy) or over 35 (geriatric pregnancy), according to a study carried out by the University of Valparaíso in Chile.

Here, the woman begins to develop conditions like diabetes, cardiopathies, heart conditions, or pyelonephriti (kidney infection).

A high risk pregnancy may also involve rubella, toxoplasmosis, syphilis, HIV, or HPV.
High risk pregnancies can have a happy ending, without endangering the health of the mother or the development baby, but close medical supervision is necessary.

There is another medical classification that applies when you find out you’re pregnant and hear, “it’s not one… it’s two!”:

  • Fraternal twins

Each zygote gets its own placenta and amniotic sac. There are two placentas and two amniotic sacs.

  • Identical twins

In the majority of cases, the embryo divides but not the placenta. More frequent check-ups are appropriate in this case (monthly sonograms for the duration of the pregnancy), since there is only one placenta nourishing the two babies.

2. Ectopic pregnancy

Ectopic pregnancies, or extrauterine pregnancies, come from a complication when the embryo descends through the Fallopian tubes and is unable to reach the uterus. Therefore, it implants in a place where it is unable to develop, according to a study carried out by the Pontifical Catholic University of Chile.

An ectopic pregnancy is very risky for the woman and the prognosis for the baby is not good . The pregnancy usually doesn’t reach the third trimester. Around week 6 or 7, the woman starts to bleed and feel intense pain.

If there is no spontaneous abortion, the doctor will likely recommend surgical intervention or certain chemotherapy treatments to save the woman’s life.

It’s important to mention that having an ectopic pregnancy doesn’t mean a woman will be unable to have an intrauterine pregnancy later on. However, extra medical supervision will be needed to make sure everything goes normally.

An ectopic pregnancy can be categorized into three types, depending on the location in which the egg fetus has implanted:

  • Tubal or ampullary

The embryo is implanted in the Fallopian tubes, causing inflammation and obstructing the tubes.

  • Isthmic

The embryo is implanted in the isthmus, at the end of the Fallopian tube.

  • Ovarian

The embryo is implanted in the ovary. It is often mistaken for a cyst.

  • Cervical

Implantation takes place in the neck of the uterus or cervix.

  • Abdominal

Implantation takes place inside the peritoneal cavity. This is a very uncommon type of pregnancy.

  • Intramural

The embryo is implanted in the myometrium, the layer of muscle in the uterine wall. This is the rarest type of all.

3. Molar pregnancy

A woman clutching her knees.

In this type of pregnancy, the egg is fertilized abnormally, as shown by an investigation carried out by the National Institute of Perinatology in Mexico. As a result, the placenta also grows abnormally, turning into a mass of cysts called a hydatidiform mole. The consequences are that:

  • The embryo cannot develop correctly and will not survive.
  • The molar pregnancy must be interrupted as soon as it is discovered.

There are two types of molar pregnancies:

  • Complete

There is no sign of normality, neither in the embryo nor the placenta tissue. All chromosomes belong to the father, when normally it is half from the mother and half from the father.

  • Partial

The placenta may show signs of normality. However, the embryo develops abnormally. Half of the chromosomes come from the mother, but those from the father appear in two groups. The baby, instead of having 46 chromosomes, has 69.

Go to your medical check-ups

No matter what kind of pregnancy you have, it is vital to get thorough, regular medical check-ups.

The doctor is the only one qualified to tell you what your probabilities are and can help both you and your baby be safe.

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.