Turner syndrome

Turner syndrome is a genetic condition in which a girl is missing all or part of one of her two X chromosomes. It occurs in roughly one in 2,000 newborn girls. It is not hereditary in the usual sense: it arises by chance and does not depend on parental age, lifestyle or anything that could have been done differently. Its main features are short stature and underdeveloped ovaries, and both respond well to treatment if it is started in good time.

Signs

They vary widely: in some girls they are visible at birth, in others the diagnosis is made in adolescence, and sometimes in adulthood, when a woman attends because of absent periods or difficulty conceiving.

In newborns

• swelling of the hands and feet;
• a broad neck with skin folds at the sides;
• a low hairline at the back of the neck;
• low-set ears;
• a broad chest with widely spaced nipples;
• heart and aortic defects, and kidney abnormalities.

In childhood and adolescence

• slowed growth — the most consistent sign; the girl gradually falls behind her peers;
• absent or delayed puberty: no breast development, no periods;
• frequent middle ear infections and hearing loss;
• multiple moles on the skin;
• an increased carrying angle at the elbows, short fourth fingers;
• difficulty with mathematics and spatial reasoning alongside normal general intelligence and good language skills — a typical profile that is worth knowing about at school;
• difficulties with peer relationships, anxiety.

In adults

• short stature — on average around 143 cm without treatment;
• absent periods and infertility;
• raised blood pressure;
• thyroid disease, coeliac disease, diabetes;
• reduced bone density;
• hearing loss that increases with age.

When to see a doctor

• a girl is clearly falling behind in height or has dropped off her own growth curve;
• there are no signs of puberty by 13;
• periods have not started by 15–16;
• a newborn has swollen hands and feet and neck folds;
• a heart or kidney abnormality has been found alongside growth delay;
• there are frequent ear infections and hearing loss;
• in an adult woman, short stature together with absent periods and infertility.

How it is diagnosed

The diagnosis is confirmed by karyotype, a chromosome analysis from a blood sample. Sometimes more cells or a tissue sample are needed if there is a mosaic variant in which some cells have a normal complement. The syndrome is sometimes detected before birth on prenatal screening; in that case the diagnosis is always confirmed after delivery.

Once the diagnosis is made, the heart and aorta (echocardiography and, at older ages, MRI), kidneys, hearing, thyroid, vision, coeliac screening, glucose and lipids are all assessed.

Treatment

The chromosome complement cannot be corrected, but almost all the manifestations can — provided treatment starts in time.

• growth hormone — started early, in the preschool years, well before puberty. It adds several centimetres to final height, and the earlier it begins, the greater the effect;
• oestrogen to start puberty, usually from around 11–12, with the dose increased gradually and a progestogen added later; treatment continues to the age of natural menopause;
• cardiology follow-up — the most important part of long-term care, because of the risk of aortic dilatation;
• blood pressure monitoring;
• annual checks of thyroid function, glucose, lipids and coeliac screening;
• regular hearing checks and prompt treatment of ear infections;
• calcium, vitamin D and weight-bearing exercise for bone;
• educational support for difficulties with mathematics and spatial tasks;
• psychological support and peer support groups — these genuinely help both girls and parents.

The question of motherhood

Spontaneous pregnancy is uncommon — around 2–5% of women, more often with the mosaic variant. The main route is treatment using donor eggs, and it works. But pregnancy in Turner syndrome requires mandatory prior assessment of the heart and aorta: the strain of pregnancy increases the risk of aortic dissection. This is not a prohibition but a reason to plan in advance and together with a cardiologist. In some girls ovarian function is still present in early adolescence, and it is then worth discussing egg preservation.

Common questions

Is it inherited? Almost always it arises by chance. The risk of recurrence in later children is not increased.

Does it affect intelligence? General intelligence is usually within the normal range. The typical difficulties involve mathematics and spatial reasoning, while language and verbal memory are often strengths.

How much height can be gained? Growth hormone adds 5–8 cm on average, and the result is better the earlier treatment starts.

Is follow-up needed in adulthood? Yes, lifelong — above all cardiology and endocrinology, plus hearing and thyroid checks.

Does it shorten life? With proper follow-up and treatment, women live full lives. The main risks relate to the heart and aorta, which is exactly why follow-up matters so much.

Online consultation

In an online consultation the doctor reviews the girl's growth curve, explains when and why a karyotype is done, helps set up the annual monitoring plan — heart, hearing, thyroid, coeliac screening — and discusses hormone replacement and planning for motherhood.

This material is for information only and does not replace a medical consultation.