IHs are usually absent at birth or a small area of pallor, telangiectasias, or duskiness may be seen. A fully formed mass at birth usually indicates a diagnosis other than IH. Superficial hemangiomas in the upper dermis have a bright-red strawberry color, whereas those in the deep dermis and subcutis, deep hemangiomas, may appear blue and be firm or rubbery on palpation. Mixed hemangiomas can have both features. A minimally proliferative IH is an uncommon type that presents with fine macular telangiectasias with an occasional bright-red, papular, proliferative component. Minimally proliferative IHs are more common in the lower body.A precise history of the growth characteristics of the IH can be very helpful in making the diagnosis. In the first 4 to 8 weeks of life, IHs grow rapidly with primarily volumetric rather than radial growth. This is usually followed by a period of slower growth that can last 6–9 months, with 80% of the growth completed by 3 months. Finally, IHs involute over a period of years. The exceptions to these growth characteristics include minimally proliferative His, which do not substantially proliferate and large, deep IHs in which noticeable growth starts later and lasts longer. If the diagnosis is not clear based on physical examination and growth history (most often in deep hemangiomas with little cutaneous involvement), then either imaging or histopathology can help confirm the diagnosis. On Doppler ultrasound, an IH in the proliferative phase appears as a high-flow, soft-tissue mass usually without direct arteriovenous shunting.
The upper lip may be "tented", exposing dental crowding, "tongue tie", or gum hypertrophy. Though the eyes do not protrude, abnormalities in the lower eyelid may give that impression. Surgery may be necessary if the eyes cannot close fully. In addition, the ears may be set low on the head or have a deformed pinna.Patients suffer from dwarfism, short lower arms, small feet, and small hands. Fingers and toes may also be abnormally short and laterally or medially bent. The thumb may be displaced and some patients, notably in Turkey, experience ectrodactyly. All patients often suffer from vertebral segmentation abnormalities. Those with the dominant variant have, at most, a single butterfly vertebra. Those with the recessive form, however, may suffer from hemivertebrae, vertebral fusion, and rib anomalies. Some cases resemble Jarcho-Levin syndrome or spondylocostal dysostosis.Genital defects characteristically seen in males include a micropenis with a normally developed scrotum and testes. Sometimes, testicles may be undescended, or the patient may suffer from hypospadias. Female genital defects may include a reduced size clitoris and underdeveloped labia minora. Infrequently, the labia majora may also be underdeveloped. Some research has shown that females may experience vaginal atresia or haematocolpos.The autosomal recessive form of the disorder tends to be much more severe. Examples of differences are summarized in the following table:

Associated conditions
Medical conditions include frequent ear infection, hearing loss, hypotonia, developmental problems, respiratory problems, eating difficulties, light sensitivity, and esophageal reflux.Data on fertility and the development of secondary sex characteristics is relatively sparse.