What is the infantile uterus and what is the likelihood of pregnancy?

By BSc, MSC, PhD (gynecologist) and BSc, MSc (embryologist).
Last Update: 08/06/2021

Infantile uterus or womb is a uterine malformation that consists of the insufficient development of the reproductive organ in charge of gestation: the uterus.

This alteration is also known as uterine hypoplasia or hypoplastic uterus due to its lack of maturity.

Despite the smaller size of the uterus, these women do not always have infertility and some can carry a pregnancy without problems.

What does a hypoplastic uterus look like?

The approximate measurements of the normal uterus in an adult woman are 7 cm x 5 cm x 3 cm, although there are variations if the woman has already given birth.

The pathology of the infant womb will be more or less serious depending on when the uterus stopped growing and its measurements. We can distinguish the following types:

Fetal uterus
also called embryonic hypoplasia. The growth of the uterus stops just after birth and, therefore, its measurements do not reach 4 cm. Women with such small uteruses have amenorrhea and infertility, as they will not be able to maintain a pregnancy.
Infant or adolescent uterus
the growth of the uterus stops in infancy and can reach a length of about 5 cm. In this case, it is possible to conceive, but the pregnancy will be considered high-risk because of the high probability of miscarriage and premature birth.

Occasionally, the growth of the ovaries and fallopian tubes may also be affected and the size of the ovaries and fallopian tubes may be smaller. Also, the vagina is usually shallow and has less elastic walls.

Causes

The poor development of the uterus and its lack of maturity can have several causes, although the most common are infant malnutrition and fetal malformations.

Below, we will list all the possible causes that result in an infant womb:

  • Malnutrition throughout a woman's lifetime
  • Malformation of the fetus in the womb
  • Family history
  • Miscarriages that deform the uterus
  • Infections, toxins, or trauma to the uterus
  • Tumors of the hypothalamus or pituitary gland, or even the ovaries
  • Big efforts at an early age: girl athletes
  • Chronic infectious diseases
  • Alcohol, tobacco and other drugs

In addition to the immaturity of the uterus, there are other uterine alterations that can affect female fertility. If you are interested in knowing them in detail, you can continue reading here: Uterine malformations in women.

Diagnosis

When a female reaches puberty, around 11-13 years of age, her reproductive organs reach maturity and begin to function. At this time, secondary sexual characteristics appear, including the first menstruation (menarche).

If menstrual bleeding does not appear in adolescent girls or if it comes late, around the age of 16, it is possible that there is some alteration in the reproductive or endocrine system.

The main symptom of uterine hypoplasia is the absence of menstruation (amenorrhea), although some women do have irregular and painful periods.

At the first gynaecological visit, measurements of the uterus will be taken by ultrasound, as well as a hormonal analysis. With both results, it is possible to diagnose whether a woman has an infantile or immature uterus.

In other cases, uterine hypoplasia is discovered later, when the woman is unable to conceive or has recurrent miscarriages.

The gynecologist may also consider the possibility of performing a hysteroscopy in order to observe the uterine interior and make a more conclusive diagnosis.

Is pregnancy possible?

The possibility of achieving a full-term pregnancy will depend, firstly, on the size of the uterus and, secondly, on the degree of maturity of the uterine tissues.

In principle, the functionality of the uterine tissues can be achieved with the appropriate hormonal treatment, based on estrogens and progesterone. In this way, the growth and maturation of the endometrium (inner layer of the uterus) is achieved.

However, even if pregnancy is achieved naturally with or without hormone treatment, this pregnancy is considered high risk due to the small space in the uterine cavity to allow the baby to grow.

Possible complications that may arise throughout pregnancy and/or childbirth include the following:

Pregnant women with an infant womb must follow a strict medical control during the whole gestation in order not to run these risks and to be able to give birth to a healthy baby.

FAQs from users

What reproductive options does a woman with infantile uterus have to become a mother?

By Dr. Marita Espejo Catena BSc, MSC, PhD (gynecologist).

The infantile uterus is a congenital abnormality of the female genital tract included in the U1 group of the European Society of Reproduction and Embryology (ESHRE) and the European Society of Gynaecological Endoscopy (ESGE). This group to which it belongs is called the dysmorphic uterus and. More precisely, the infantile uterus, is defined as a uterus with a narrow but not thickened uterine cavity of the lateral walls and a 1/3 correlation of uterine body and 2/3 of cervix.
It can be differenciated from the hypoplastic uterus or "naïve uterus" which would include those cases of smaller uterus.
In either case, the chances of gestation remain intact because in the case of the infantile uterus of the ESHRE/ESGE classification, the uterine cavity is configured by a healthy tissue without areas of fibrosis, and because in the case of the hypoplastic uterus, this should be considered a variant of normality.

What are the consequences of having a small uterus?

By Zaira Salvador BSc, MSc (embryologist).

The symptoms and consequences of having an infantile womb will depend on the degree of hypoplasia and the size of the womb. It is possible that the woman may never have a menstrual period or, if she does have one, it may be scanty and painful.

On the other hand, having a small uterus during pregnancy can lead to complications such as miscarriage, intrauterine fetal death or very premature delivery.

Is there any treatment to correct a hypoplastic uterus?

By Zaira Salvador BSc, MSc (embryologist).

No. There is no effective treatment to get the uterus to the right size, not even surgery. As we have said, the only thing these women can do to be able to have a child is to follow hormone therapy, a balanced diet and plenty of rest during pregnancy to reduce the risk of miscarriage.

Suggested for you

Uterine infertility can be caused by a variety of factors that affect the uterus at different levels. For more information related to this topic, you can access the following article: Uterine Factor Infertility - Diagnosis, Characteristics & Treatment.

Those women with a very small or rudimentary uterus who are unable to gestate will have to resort to adoption or surrogacy in order to become mothers. If you want to know what this procedure consists of, we recommend you to read the following post: What Is Surrogacy? - Definition & Types.

Our editors have made great efforts to create this content for you. By sharing this post, you are helping us to keep ourselves motivated to work even harder.

References

J F Carvalho, A Cubal, S Torres, F Costa, A Torgal. Hypoplastic uterus: the importance of gynaecological ultrasound in its diagnosis--case report and review of the literature. J Obstet Gynaecol. 2014 May;34(4):367-8. doi: 10.3109/01443615.2013.870539.

Valérie Hétu, Evelyne Caron, Diane Francoeur. Hypoplastic uterus and clitoris enlargement in Swyer syndrome. J Pediatr Adolesc Gynecol. 2010 Feb;23(1):e43-5. doi: 10.1016/j.jpag.2009.03.004.

Xichuang Chen, Yuan Hong, Panpan Zheng, Yaping Qin, Xiaoyan Zhang, Jinhua Feng, Jianlin Ye, Huizhu Song, Xiaohong You. Efficacy of kidney-tonifying traditional Chinese medicine prescriptions in hypoplastic uterus treatment: a systematic review and meta-analysis. J Obstet Gynaecol Res. 2014 Jul;40(7):1913-24. doi: 10.1111/jog.12451.

FAQs from users: 'What reproductive options does a woman with infantile uterus have to become a mother?', 'What are the consequences of having a small uterus?' and 'Is there any treatment to correct a hypoplastic uterus?'.

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Authors and contributors

Dr. Marita Espejo Catena
Dr. Marita Espejo Catena
BSc, MSC, PhD
Gynecologist
Graduated in Medicine and Surgery from the University of Valencia in 1992. Specialist in Gynaecology and Obstetrics. Doctor in Medicine from the University of Valencia in 2000. Master in Assisted Human Reproduction by the Rey Juan Carlos University and IVI in 2008. Currently, she is the director of Instituto FIVIR. More information about Dr. Marita Espejo Catena
License: 464616497
 Zaira Salvador
Zaira Salvador
BSc, MSc
Embryologist
Bachelor's Degree in Biotechnology from the Technical University of Valencia (UPV). Biotechnology Degree from the National University of Ireland en Galway (NUIG) and embryologist specializing in Assisted Reproduction, with a Master's Degree in Biotechnology of Human Reproduction from the University of Valencia (UV) and the Valencian Infertility Institute (IVI) More information about Zaira Salvador
License: 3185-CV

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