The Signs of Turner Syndrome in Pregnancy & Newborns

What is Turner Syndrome?

Most people are born with two sex chromosomes. Females inherit a pair of two X chromosomes, one from each parent, while males will inherit an X chromosome from their mother and a Y chromosome from their father. Girls and women with Turner syndrome (TS), however, only have one X chromosome, due to the second one being missing or significantly altered.

The symptoms of Turner syndrome can vary significantly from individual to individual, and therefore there is a wide range in the age at which girls and women with Turner syndrome are diagnosed.

Learn more in this video by McMaster University, which discusses Turner Syndrome in depth.

Some individuals are diagnosed with Turner syndrome in pregnancy or infancy, while others won’t receive a diagnosis until adolescence or even adulthood. Early diagnosis, and the possibility of early treatment for the symptoms of Turner syndrome, has many benefits. With treatment it is largely a manageable condition and girls with Turner syndrome go on to live independent and healthy lives, which is why being aware of the signs during pregnancy and infancy is so important.

Signs of Turner Syndrome During Pregnancy

While not always present during pregnancy, there are a few signs of Turner Syndrome which may be visible during routine ultrasounds.

These may include:

Fluid around the back of the neck/body (hydrops fetalis)
Heart defects, ranging from mild to severe
Kidney defects

In addition to these signs, several tests can be used to detect and diagnose Turner syndrome in utero, including Non-Invasive Prenatal Testing, chorionic villus sampling, and amniocentesis.

Non-Invasive Prenatal Testing (NIPT) analyses the fetal DNA released by the placenta into the mother’s blood for various chromosomal abnormalities, including Turner syndrome. It is not a diagnostic test, but a screening tool. For a more definitive confirmation of Turner Syndrome during pregnancy, other tests are needed.

One study examining the NIPT tests’ accuracy found 40% of the babies tested and considered ‘high risk for Turner Syndrome’ were confirmed to not have Turner Syndrome with further genetic testing (Bedei et al., 2025).

To read about chorionic villus sampling and amniocentesis, read “Genetic Testing: Diagnosing Turner Syndrome.”

Signs of Turner Syndrome in Infancy

These symptoms, especially in combination, should flag the need for genetic testing. However, many cases of Turner syndrome can be very mild with little to no apparent symptoms.

The signs of Turner Syndrome in infants can vary greatly but often include the following symptoms:

Wide or weblike neck
Low-set ears
Broad chest with widely spaced nipples
High, narrow roof of the mouth (palate)
Arms that turn outward at the elbows
Fingernails and toenails that are narrow and turned upward
Swelling of the hands and feet, especially at birth
Slightly smaller than average height at birth
Slowed growth
Cardiac defects
Low hairline at the back of the head
Receding or small lower jaw
Short fingers and toes

After Diagnosis

nce the TS diagnosis has been confirmed, there are tests that your healthcare team will conduct to confirm or rule out certain symptoms. These may include:

Echocardiogram, ultrasound of the heart
Ultrasound of the reproductive organs
Ultrasound of the kidneys
Monitoring of height on a growth curve

All girls with Turner syndrome are unique and may require more or less monitoring for certain aspects of their health care. However, most will have short stature as adults, on average being about 20 cm shorter than adult women without Turner syndrome. For this reason, growth hormone treatment will be discussed with your pediatric endocrinologist and is typically initiated around 4-6 years of age. Maximum benefits appear to be present the earlier treatment is started as growth plates start to close when adolescence is reached (Aversa et al., 2024).

While receiving a Turner syndrome diagnosis can be daunting, with treatment it is largely a manageable condition and girls with TS go on to live independent and healthy lives.

If you are a parent navigating the diagnosis, you are not alone! Below are some resources you may find useful:

Parent Registry – Join to connect with TSF and stay up-to-date on our events and resources
Prenatal Testing & Information About Turner Syndrome Booklet – A resource for parents to understand the prenatal diagnosis more in-depth
Star Sisters – TSF’s online group for patients & parents to connect and get support

References

Aversa, T., Li Pomi, A., Pepe, G., Corica, D., Messina, M. F., Coco, R., Sippelli, F., Ferraloro, C., Luppino, G., Valenzise, M., & Wasniewska, M. G. (2024). Growth Hormone Treatment to Final Height in Turner Syndrome: Systematic Review. Clinical Therapeutics, 46(2), 146-153. https://doi.org/10.1016/j.clinthera.2023.12.004

Bedei, I., Bruder, J., Lund, I. C. B., Thomsen, S. H., Vogel, I., Maciel‐Guerra, A. T., Alvarez‐Nava, F., Crenshaw, M. L., Axt‐Fliedner, R., Gravholt, C. H., & Skakkebæk, A. (2025). Non‐Invasive Prenatal Testing by Cell‐Free DNA (cfNIPT) for Detecting Turner Syndrome With Mosaicism and Structural Variants—Prenatal Findings and Postnatal Outcomes. American Journal of Medical Genetics Part C: Seminars in Medical Genetics, 199(2), 124–133. https://doi.org/10.1002/ajmg.c.32136

John Hopkins Medicine. (n.d.). Amniocentesis. Retrieved April 29, 2026, https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/amniocentesis

John Hopkins Medicine. (n.d.). Chorionic Villus Sampling. Retrieved April 29, 2026, https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/chorionic-villus-sampling-cvs

John Hopkins Medicine. (n.d.). Turner Syndrome. Retrieved April 29, 2026, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/turner-syndrome

Mayo Clinic Staff (2022, Feb 11). Turner Syndrome. Mayo Clinic. Retrieved April 29, 2026, from https://www.mayoclinic.org/diseases-conditions/turner-syndrome/symptoms-causes/syc-20360782

Prenatal Screening Ontario. (n.d.). Turner Syndrome. Retrieved April 29, 2026, from https://www.prenatalscreeningontario.ca/types-of-screening/chromosome-screening/chromosome-differences/turner-syndrome