Could things like pollution, the mother’s health, any medication the mother is taking, or the delivery process affect the risk of the baby contracting Transient Neonatal Pustular Melanosis (TNPM)? Despite its harmless nature, awareness can prevent misdiagnosis, reduce unnecessary treatments, and act as an indicator of possible immune deficiencies in the baby.

TNPM is the most common rash in healthy neonates; it is benign and affects about 50% of term newborns.¹ It is a self-limiting physiological rash rarely found among preterm infants; this infection can begin at one to two days of age but can occur any time until day four.¹

Here we will look at the disease, understand it and the environmental and maternal factors that could contribute to this disease. This way, we can have a holistic understanding of TNPM.

What even is TNPM?

Scientifically, TNPM is defined as a rare disorder that affects both sexes equally. Its aetiology is unknown, and its association with maternal and environmental issues varies among different studies. Some saying there is an association, while others say there is none.²

TNPM is characterised by lesions that measure 1 to 5 mm in diameter that appear on the forehead, temporal areas, cheeks, neck, back, and buttocks. The baby will have tiny pus-filled spots that break open and leave behind small dark spots or patches. These spots are not painful, itchy and do not come with a fever. They are simply just cosmetic.¹

The most important characteristic to look for is whether the skin between the lesions is visually healthy and not inflamed or red.

TNPM affects more black than white infants. In 2013, incidence rates ranged from 0.6% in white infants to 4.4% in black infants ³. The symptoms disappear within three weeks at most without any treatment. This is why it is of great importance to know this disease holistically to avoid misdiagnosis can be a cause for antibiotic or medication misuse in neonates.

So, let’s have a look at why TNPM happens.

Environmental factors

The environment can play a subtle role in the development of TNPM in neonates. Despite the benign nature of the disease, some environmental factors may contribute to immune system priming or skin sensitivity in newborn babies. This may increase susceptibility and severity of the condition.

Exposure to pollutants or toxins during pregnancy

Exposure to environmental toxins during pregnancy can play a significant role in the development of the skin and immune system of the fetus.⁴ This is because some toxins in the environment may cross the placental barrier and interact with the developing fetus.

Common toxins that can cause this effect are through air pollution, like nitrogen dioxide and particulate matter. Heavy metals like lead, arsenic, and mercury and pesticides or chemical solvents. These toxins can modulate fetal immune responses that can lead to mild inflammatory skin changes after birth. There is no established direct link between TNPM and these environmental factors, but there has always been a link between pollutants and their effect on immune and skin barrier development issues.⁵

Maternal skin care products or medications

Products and medications applied or ingested by the mother during pregnancy have a high chance of affecting the developing fetus indirectly or otherwise. Topical creams such as steroids to treat eczema, certain oils, and skin care routine products may increase susceptibility of TNPM in the fetus.⁶ Simply, these get absorbed into the skin and can possibly reach the baby through the placenta.

Some ingredients may have side effects that can be hormonal or allergenic, which could influence the sensitivity or inflammatory response of the fetus’ skin after birth.⁶ Similarly, ingredients in some medications can increase TNPM susceptibility in infants. Corticosteroids and or antibiotics are examples of medications that can affect the fetus in the placenta. These drugs are known to alter the fetus’s immune system, lowering its tolerance and in turn affecting skin maturation.⁷

As a parent, it is important to note that more research still needs to be done to understand the correlation between skin care products or medications and TNPM. Be sure to speak to your health care professional, gynaecologists, or dermatologists during pregnancy to gain advice on the products that you are using on your skin. If it happens that you do not have access to these resources, make sure to do your research so you are making informed decisions about the products and medications you are including in your daily routine.

Hospital environment (hygiene, temperature, etc.)

The environment where the baby is born can increase the risk of widespread lesions caused by TNPM. Hospitals can sometimes be warm and moist; environmental characteristics that are not favourable to skin conditions, hence may play a role in negatively influencing neonatal skin outcomes.

Newborns have high sensitivity to temperature and humidity- when it is too hot and humid, the pustules can rupture. When the environment is too dry, it can suck the moisture out of the skin. This generally affects the skin barrier, increasing the sensitivity of the baby’s skin.

Poor hygiene in the hospital environment can greatly contribute to triggering TNPM in newborns. Exposure to irritants such as antiseptics may disrupt the skin microbiome, hence irritating the skin.

Maternal factors

How healthy the mother is is of great influence on fetal development. As a parent, you should never blame yourself if your baby is diagnosed with TNPM. Because, as much as the mother can work to make sure the baby is as healthy as possible during pregnancy, they cannot know that their child will be affected by TNPM. It is still important to understand that there are certain maternal factors that may increase TNPM susceptibility in the infant.

Nutritional status and general health

To ensure the fetus’s skin is developing in the best possible manner, the mother needs to eat well. She needs to acquire adequate nutrients in her daily meals and make sure to hydrate and take supplements to cover what the body cannot produce on its own. Despite there being no direct correlation between TNPM and poor maternal nutrition, underdevelopment of the skin during pregnancy may increase susceptibility to skin lesions due to reduced skin strength.

A pregnant woman can be affected by various nutritional deficiencies, which can range from low levels of Zinc, Vitamin A, fatty acids, to iron can compromise the formation of the fetus’ skin barrier.⁷

Diseases like hypertension and diabetes can also play a role in poor placental function. This can directly impact the development of the pregnancy, hence affecting the immunity and skin barrier development of the fetus.

History of skin conditions or allergies

As a parent, if you have a history of any skin conditions, it is important to know them, as you may have shared these traits with your baby. Some skin conditions may genetically predispose your child to skin or immune system issues. Additionally, a family history of skin conditions may increase the susceptibility of the neonate’s skin to the environment.

Delivery-related factors

Several factors during the time of delivery can influence how and when TNPM presents on the baby. Different forms of delivery can affect the baby’s initial contact with microbiomes, hence affecting the neonate’s immune system. Delivery-related factors do not cause TNPM, but they can indirectly induce the symptoms of the disease through compromising the baby’s immune system, hence affecting the skin's response to birth.

Mode of delivery (vaginal vs. cesarean)

No direct causation has been established between the mode of delivery and TNPM, only that it can act as a contributing factor. Vaginal delivery is supposedly the best way to reduce susceptibility to TNPM because of the good bacteria the baby is exposed to during birth.⁸ Exposure to the mother’s vaginal and intestinal microbiota has been said to help train the baby’s immune system. Unlike caesarean delivery, which can be a cause for issues with the baby’s immune response, hence leading to skin conditions such as TNPM.

Use of intrapartum antibiotics

As discussed, introducing antibiotics during pregnancy can affect the fetus’s health and immune system. A link has been established between exposure to antibiotics during pregnancy and a higher risk of neonatal rashes or varied allergic conditions. A lot more research still needs to be done, so do not take this at face value, but it is something to consider ⁹.

Using antibiotics during labour to prevent infections affects the microbiome in the mother, which in turn affects the neonates’ microbiomes. The nature of an antibiotic is to kill all bacteria, good or bad. This is why it is important to be cautious of how they are used and to make sure they are used in a way that does not affect the baby.

Summary

TNPM is a self-limiting benign issue that works itself out very quickly. It is mostly cosmetic and does not cause any pain to the baby. Because of the presenting characteristics of this disease, it can be very easy to misdiagnose. This can lead to neonates being prescribed medication that they do not need, which may hurt the baby more than it heals them.

The cause of TNPM has not yet been pinpointed, researchers are still working to understand what exactly could lead to these lesions. Through these efforts, they have been able to discover various contributing factors that parents and healthcare providers can be aware of to aid in the diagnosis and treatment of TNPM.

When your child presents with the symptoms of TNPM, be sure to consult your doctor as soon as you can to ensure the right course of treatment is administered.

Transient Neonatal Pustular Melanosis is a benign, self-limiting skin condition that can be found in newborn babies. It looks like small pustules; these can rupture and leave pigmentation behind. TNPM does not require any intervention or treatment as it goes away in one to three weeks with no long-term effects to the neonate.

The easiest way to determine whether a baby has TNPM is to look at the skin around the pustules; it will be clear and healthy. There has not been a clear cause for TNPM, but researchers have been able to identify several factors that can influence TNPM in a baby.

These range from environmental to delivery-related factors. As a parent, you should take some time to understand this influence so you can know what to do to reduce the chances of your baby being affected by TNPM. Knowing these and abiding by them does not mean your child may not contract TNPM, but it will make it easier to diagnose, hence preventing further issues.