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Start free with EleplanMonosomy X syndrome
ORPHA:99226Etiological subtype
What it is
Orphanet has not published a description for this disease yet. The identifiers, classification and cross-references below are still current.
Key facts
- Age of onset
- Antenatal, Childhood, Infancy, Neonatal
- Inheritance
- Not applicable
- Classified as
- Etiological subtype
Recorded for the broader condition
- Prevalence
- 1-9 / 100 000 (at birth, Europe)Turner syndrome
Orphanet records these for the broader condition rather than for this specific form. They are a starting point, not a figure for this subtype — subtypes often differ, and some are defined by being rarer than the condition they sit under.
Signs and symptoms
Very common80–99%
21- Abnormal forearm bone morphology
- Abnormality of the ovary
- Aplasia/Hypoplasia of the nipples
- Cubitus valgus
- Delayed puberty
- Delayed skeletal maturation
- Enlarged thorax
- Female infertility
- Growth delay
- High urinary gonadotropins (primary hypogonadism)
- Increased circulating gonadotropin level
- Increased upper to lower segment ratio
- Intrauterine growth retardation
- Osteopenia
- Osteoporosis
- Postnatal growth retardation
- Premature ovarian insufficiency
- Short neck
- Short stature
- Short sternum
- Wide intermamillary distance
Common30–79%
37- Abnormal dermatoglyphics
- Anxiety
- Atypical behavior
- Broad neck
- Dermatoglyphic ridges abnormal
- Dilatation of the aortic arch
- Elevated circulating hepatic transaminase concentration
- Enlargement of the distal femoral epiphysis
- Failure to thrive in infancy
- Genu valgum
- Glucose intolerance
- Hashimoto thyroiditis
- Hearing impairment
- Hepatic steatosis
- High, narrow palate
- High palate
- Hypermobility of toe joints
- Hypertension
- Hypoplastic toenails
- Impaired use of nonverbal behaviors
- Irregular proximal tibial epiphyses
- Kyphosis
- Low posterior hairline
- Low-set ears
- Micrognathia
- Neck pterygia
- Obesity
- Primary amenorrhea
- Recurrent otitis media
- Retrognathia
- Secondary amenorrhea
- Shield chest
- Short 4th metacarpal
- Short 5th metacarpal
- Specific learning disability
- Thickened nuchal skin fold
- Webbed neck
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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