Benign cephalic histiocytosis (also known as "Histiocytosis with intracytoplasmic worm-like bodies", and not to be confused with "Neonatal cephalic pustulosis") is a rare cutaneous condition affecting boys and girls equally, characterized by skin lesions that initially present on the head in all cases, often the cheeks, eyelids, forehead, and ears.

Transient neonatal pustular melanosis (also known as "transient neonatal pustulosis" and "lentigines neonatorum") is a cutaneous condition that presents at birth with 1- to 3-mm flaccid, superficial fragile pustules, some of which may have already resolved in utero, leaving pigmented macules.

Benign neonatal hemangiomatosis is a cutaneous condition in infants, characterized by multiple cutaneous lesions without evident visceral hemangiomas.

Neonatal acne (also known as "Acne infantum", "Acne neonatorum", and "Neonatal cephalic pustulosis" (not to be confused with "Benign cephalic histiocytosis")) is an acneiform eruption that occurs in newborns or infants, and is often seen on the nose and adjacent portions of the cheeks.

The main cause of this condition is not known, but it could be due to the increased sensitivity of the infant's sebaceous glands to maternal hormones during pregnancy which also leads to a variety of skin conditions in the newborn. Typically, it peaks at around 2 months and rarely needs treatment. Sometimes gels or ointments are given.

Noma neonatorum is a cutaneous condition, a manifestation of infection, usually "Pseudomonas aeruginosa" septicemia, and has been reported almost exclusively in developing countries.

Neu-Laxova syndrome presents with severe malformations leading to prenatal or neonatal death. Typically, NLS involves characteristic facial features, decreased fetal movements and skin abnormalities.

Fetuses or newborns with Neu–Laxova syndrome have typical facial characteristics which include proptosis (bulging eyes) with eyelid malformations, nose malformations, round and gaping mouth, micrognathia (small jaw) and low set or malformed ears. Additional facial malformations may be present, such as cleft lip or cleft palate. Limb malformations are common and involve the fingers (syndactyly), hands or feet. Additionally, edema and flexion deformities are often present. Other features of NLS are severe intrauterine growth restriction, skin abnormalities (ichthyosis and hyperkeratosis) and decreased movement.

Malformations in the central nervous system are frequent and may include microcephaly, lissencephaly or microgyria, hypoplasia of the cerebellum and agenesis of the corpus callosum. Other malformations may also be present, such as neural tube defects.

The mucous membranes of the mouth develop ulcers, and rapid, painless tissue degeneration ensues, which can degrade tissues of the bones in the face.

In a condition sometimes called noma pudendi, noma can also cause tissue damage to the genitals.

Natal teeth are teeth that are present above the gumline (have already erupted) at birth, and neonatal teeth are teeth that emerge through the gingiva during the first month of life (the neonatal period).

The incidence of neonatal teeth varies considerably, between 1:700 and 1:30,000 depending on the type of study; the highest prevalence is found in the only study that relies on personal examination of patients.

Neonatal ichthyosis–sclerosing cholangitis syndrome (also known as "NISCH syndrome" and "ichthyosis–sclerosing cholangitis syndrome") is a cutaneous condition caused by mutations in the Claudin 1 gene.

Beckwith–Wiedemann syndrome (; abbreviated BWS) is an overgrowth disorder usually present at birth, characterized by an increased risk of childhood cancer and certain congenital features.

Common features used to define BWS are:

- macroglossia (large tongue),

- macrosomia (above average birth weight and length),

- microcephaly

- midline abdominal wall defects (omphalocele/exomphalos, umbilical hernia, diastasis recti),

- ear creases or ear pits,

- neonatal hypoglycemia (low blood sugar after birth).

- Hepatoblastoma

Most of the time, natal teeth are not related to a medical condition. However, sometimes they may be associated with:

- Ellis–van Creveld syndrome

- Hallermann–Streiff syndrome

- Pierre Robin syndrome

- Sotos syndrome

Hemangiomatosis may refer to:

- Diffuse neonatal hemangiomatosis

- Benign neonatal hemangiomatosis

Noma is a rapidly progressive, polymicrobial, often gangrenous infection of the mouth or genitals.

The diagnosis is usually based on clinical features present at birth.

Ultrasound in the second trimester may show abnormalities associates with NLS, including polyhydramnios, intrauterine growth restriction, microcephaly, proptosis and decreased fetal motility.

Most children with BWS do not have all of these five features. In addition, some children with BWS have other findings including: nevus flammeus, prominent occiput, midface hypoplasia, hemihypertrophy, genitourinary anomalies (enlarged kidneys), cardiac anomalies, musculoskeletal abnormalities, and hearing loss. Also, some premature newborns with BWS do not have macroglossia until closer to their anticipated delivery date.

Given the variation among individuals with BWS and the lack of a simple diagnostic test, identifying BWS can be difficult. In an attempt to standardize the classification of BWS, DeBaun et al. have defined a child as having BWS if the child has been diagnosed by a physician as having BWS and if the child has at least two of the five common features associated with BWS (macroglossia, macrosomia, midline abdominal wall defects, ear creases/ear pits, neonatal hypoglycemia). Another definition presented by Elliot et al. includes the presence of either three major features (anterior abdominal wall defect, macroglossia, or prepostnatal overgrowth) or two major plus three minor findings (ear pits, nevus flammeus, neonatal hypoglycemia, nephromegaly, or hemihyperplasia).

While most children with BWS do not develop cancer, children with BWS do have a significantly increased risk of cancer. Children with BWS are most at risk during early childhood and should receive cancer screening during this time.

In general, children with BWS do very well and grow up to become adults of normal size and intelligence, usually without the syndromic features of their childhood.

Campomelic dysplasia (CMD) is a rare genetic disorder characterized by bowing of the long bones and many other skeletal and extraskeletal features.

It is frequently lethal in the neonatal period due to respiratory insufficiency, but the severity of the disease is variable, and some patients survive into adulthood.

The name is derived from the Greek roots "campo" (or "campto"), meaning bent, and "melia", meaning limb.

An unusual aspect of the disease is that up to two-thirds of affected 46,XY genotypic males display a range of Disorders of Sexual Development (DSD) and genital ambiguities or may even develop as normal phenotypic females as in complete 46 XY sex reversal.

An atypical form of the disease with absence of bowed limbs is called, prosaically, acampomelic campomelic dysplasia (ACD) and is found in about 10% of patients, particularly those surviving the neonatal period.

In fetal and neonatal life the ductal plates are remodeled. The malformations can be atretic or fibrocystic.

The presentation is dependent upon the underlying cause. The course can be rapid or chronic.

While the definitive presentation of the disease is a patient having bowed lower limbs and sex reversal in 46,XY males, there are other clinical criteria that can be used, absent these characteristics, to make the diagnosis. Patients may present with underdeveloped shoulder blades, shortened and angulated lower limbs, a vertically oriented and narrow pelvis, an enlarged head, an undersized jaw, cleft palate, flat nasal bridge, low set ears, club feet, dislocated hips, 11 pairs of ribs instead of 12, or bone abnormalities in the neck and spine. Respiratory distress can be caused by an underdeveloped trachea which collapses on inhalation or by insufficient rib cage development.

Persistent tunica vasculosa lentis is a congenital ocular anomaly. It is a form of persistent hyperplastic primary vitreous (PHPV).

It is a developmental disorder of the vitreous. It is usually unilateral and first noticed in the neonatal period. It may be associated with micropthalmos, cataracts, and increased intraocular pressure. Elongated ciliary processes are visible through the dilated pupil. A USG B-scan confirms diagnosis in the presence of a cataract.

Diffuse neonatal hemangiomatosis is a potentially fatal disorder with multiple cutaneous and systemic hemangiomas. The most common site of internal organ involvement is the liver. Death can result from high-output cardiac failure as a result of arteriovenous shunting. Early detection and treatment with steroids results in most patients remaining healthy, with serious problems developing for some patients during the hemangiomas growth phase.

In the recessive form corneal clouding is observed at birth or within the neonatal period, nystagmus is often present, but no photophobia or epiphora is seen. In the autosomal dominant type corneal opacification is usually seen in the first or second year of life and progresses slowly, and nystagmus is infrequently seen.

Erythema toxicum neonatorum (also known as erythema toxicum, urticaria neonatorum and toxic erythema of the newborn) is a common rash in neonates. It appears in up to half of newborns carried to term, usually between day 2–5 after birth; it does not occur outside the neonatal period.

Erythema toxicum is characterized by blotchy red spots on the skin with overlying white or yellow papules or pustules. These lesions may be few or numerous. The eruption typically resolves within first two weeks of life, and frequently individual lesions will appear and disappear within minutes or hours. It is a benign condition thought to cause no discomfort to the baby.

Majewski's polydactyly syndrome, also known as polydactyly with neonatal chondrodystrophy type I, short rib-polydactyly syndrome type II, and short rib-polydactyly syndrome, is a lethal form of neonatal dwarfism characterized by osteochondrodysplasia (skeletal abnormalities in the development of bone and cartilage) with a narrow thorax, polysyndactyly, disproportionately short tibiae, thorax dysplasia, hypoplastic lungs and respiratory insufficiency. Associated anomalies include protruding abdomen, brachydactyly, peculiar faces, hypoplastic epiglottis, cardiovascular defects, renal cysts, and also genital anomalies. Death occurs before or at birth.

The disease is inherited in an autosomal recessive pattern.

It was characterized in 1971.

The rash is composed of small papular lesions, each on a separate reddened base.