It is alarming as a parent when you cannot understand what's happening with your child. It can be worrying when the doctor says “Let it run its course.” Going through all these motions with a newborn during the first four weeks of life is normal. Why? Because newborns tend to have several skin issues during this time.¹

These skin issues are often harmless and resolve within a period. Despite this, there are still some harmful ones that could be:¹

• Serious infections
• Congenital skin diseases 
• Malignant tumours

However, harmless conditions that resolve without treatment are:²

• Milia
• Cutis marmorata
• Congenital melanocytosis 
• Benign neonatal pustular eruptions 

Milia occurs in 40-50% of newborns and affects babies of all ethnic backgrounds and both sexes equally.³ Despite this, there is less occurrence among premature babies. Milia doesn't need treatment but has a good outcome without complications.²

Understanding milia

Milia is a skin condition that develops when the skin structure is immature.¹ It is a common rash that occurs at birth in most healthy newborns.^1,2 Despite that,  prematurity in neonates may delay the appearance of milia. ¹ Milia is a harmless keratin-filled cyst that often appears in babies.^1,2 The leading cause of milia is keratin retention due to skin structure immaturity.¹

The appearance of milia

Milia looks like tiny yellow or white snowdrops on your child's face. In reality, those snowdrops are superficial cysts.² Although milia often affects the face, it can occur in other body areas. These locations include:

• Cheeks
• Forehead
• Chin
• Scalp
• Upper trunk
• Lower limb
• Mouth 
• Genitalia^{3, 7}

Milia, which affects the mouth and palate, has a name; milia in the mouth are called Epstein pearls, whilst milia in the palate are called Bohn nodules.⁷

Types of milia

There are two types of milia: primary and secondary milia. 

Primary milia

Arise from where the oil gland meets the hair follicle of vellus hair follicles- often referred to as peach fuzz.^{3, 4} 

• Benign milia in newborns: this is typically temporary and due to blocked immature pores
• Genetic skin disorders, such as Orofaciodigital syndrome type 1
• Congenital causes: Basan syndrome, familial profuse congenital milia, nevus depigmentosus
• Milia en plaque: aka nodular grouped milia is a rare disorder where milia cysts cluster, often near the ear 
• Multiple eruptive milia: sudden onset milia on the face, neck and trunk, can occur in adults

Secondary milia

These arise from the eccrine or sebaceous (sweat) ducts or epidermis layer of skin, instead of the hair follicle. It can appear because of:^{3, 7}

• Medications: steroid ointments and immunosuppressants
• Diseases: herpes zoster, bullous pemphigoid, eczema, bullous lupus erythematosus Epidermolysis bullosa, Porphyria cutaneatarda
• Trauma-related cutaneous healing: burns, radiotherapy, and skin grafts

The difference between milia, miliaria, and neonatal acne

Milia, miliaria, and neonatal acne are different skin conditions in newborns. Here are the differences between Milia, Miliaria, and Neonatal  Acne:^{12, 6}

Diagnosis, treatment and prevention of milia in newborns and infants

Diagnosis 

Diagnosing milia in newborns and infants is easy.¹ Doctors often make diagnoses based on clinical appearance alone.¹ Milia is a condition that seldom requires incisions or drainage to diagnose.⁴ Despite that, doctors can use them to confirm Milia's diagnosis.⁴ 

Clinical tools used to diagnose milia include:^1,4

• Histological finding: it shows small central keratinous material cysts with stratified squamous epithelium (the layers of skin cells)
• Physical examination: Your GP will usually observe:
  • Small white or yellow lumps 
  • Papules (or cysts) less than 3mm in diameter
  • They have a smooth dome-like shape
  • A faint blue hue on darker skin tones
  • Solitary or many grouped lesions

How to treat milia in newborns and infants

Milia treatment is not required in newborns, as the lesions leave without scarring within a few weeks.^1,3 Despite that, milia can stay for several months and spread throughout the body.^1,3

Prevention

Milia in newborns and infants is not a condition where prevention is necessary or possible. Despite that, some measures can help with its occurrence. These include: 

• Gently wash your newborn face every day 
• Pat dry with a clean towel 
• Avoid pinching, squeezing, and scrubbing the lumps. 

Time to seek medical advice 

Milia often resolves on its own. In babies, milia tends to resolve faster. It doesn't pose any long-term or short-term problems. Despite this, you should seek medical attention if: ⁴

• A rash colour other than white 
• Crusting around the milia lumps
• Re-occurring milia 
• Widespread milia 

It is essential to seek medical attention, especially for re-occurring and widespread milia.⁴ This could mean your baby is experiencing a condition other than congenital milia.⁴

In that case, treatments such as the following will occur: 

• Use of heat or electricity to remove them
• Cryotherapy
• A prescription for topical cream or chemical peels 
• An incision on the milia with a sterile blade to remove the contents

Summary

Milia is a common skin condition that occurs at birth. It is harmless and resembles tiny white or yellow snowdrops. Milia can appear at any point in the body but often appears on the face. It is caused by immature skin structure, which means pores can easily become blocked, and keratin retention can easily occur. Miliaria and neonatal acne are skin conditions that relate to milia but are different conditions. There are two types of milia: primary and secondary.^3,4 Milia in newborns falls under the primary type.³ There is no way to prevent milia, and often, there is no need to treat it, as it resolves on its own. Despite this, knowing when to seek medical attention is essential. If your baby has other symptoms you are concerned about, speak to your GP or health visitor.

FAQ’s

Which syndromes are associated with milia?

It is important to note that milia in newborns is not due to any underlying syndrome. It is congenital and appears on its own. Despite that, primary milia can be a symptom of Brooke-Spiegler syndrome, pachyonychia congenital type 2, or basal nevus syndrome. Secondary milia is associated with porphyria cutaneatarda and epidermolysis bullosa.⁴ 

Is Vaseline good for milia?

An optimal approach is to let Milia resolve on its own. It often does in some weeks. Despite this, you can wash your newborn face every day in a gentle motion and pat dry with a clean towel. 

Does breastfeeding cause milia?

No, it does not. Milia is a skin condition caused by immaturity, leading to keratin retention. Keratin retention leads to the formation of cysts with keratin.¹

Is milia itchy?

Milia are not itchy, painful or contagious.⁷

How long does it take for milia to disappear?

A few weeks to a month. 

Can I remove milia with a needle?

The optimal approach is to leave it alone. Like a pimple, it's best to leave it alone.

Why do babies get milia?

Not all babies get milia, but many full-term babies do. Their immature skin structure leads to keratin retention. 

Which medication causes milia?

Medications cause secondary milia. Secondary milia occurs due to underlying factors like trauma, medication or diseases. Medicines that cause milia are steroid ointments and immunosuppressants.