Newborn skin: proper care

  • 20min
  • May. 2022
  • Supported by
    • La Roche-Posay

Newborn skin: its immaturity should be taken into account


There are notable differences between the skin of a newborn baby and that of an adult.

The stratum corneum:

  • It is 30% thinner.1,2
  • It is not as well hydrated, especially during the first 2 weeks of life.3

The dermo-epidermal junction:

  • The collagen fibres are shorter and less dense.
  • The epidermal cells’ capacities for cohesion and adhesion are not yet fully developed.

It is thus more fragile than that of adults.4

Skin surface:
It is less acidic: pH is around 7 at birth, and falls quickly to reach the acidic pH of adult skin after approximately 4 weeks4
This means that babies are predisposed to inflammatory skin conditions, such as nappy rash.3


These differences demonstrate the relative permeability and immaturity of the epidermal barrier immediately after birth, and this immaturity may explain why newborn babies’ skin is so delicate, and so susceptible to chemical, physical and bacterial assaults. The functional and structural maturation of the skin is a dynamic process which remains ongoing throughout the first 2 years of life.2



A more detailed overview

Newborns’ skin microbiota

The microbiota undergoes a major change at birth, when it moves from a fluid environment (the amniotic fluid) to a gas environment that is rich in microorganisms.5,6

During the first few days of life, the rapid bacterial colonisation of the skin coincides with significant barrier function changes. The falls in transepidermal water loss (TEWL), skin pH and sebaceous activity, as well as increased water content, are among the changes that create an environment favourable to colonisation by certain bacteria and unfavourable to others.5,6

Compared to adult skin, staphylococci are present in greater numbers and the skin microbiota of the newborn resembles adult skin microbiota in moist sites, since the skin of newborn babies is more hydrated than that of adults.5,7

The delivery method plays a major role in the composition of the microbiota of newborn babies at birth.8

Babies who are born by vaginal delivery present bacterial populations on the skin that are similar to those colonising the maternal vagina, with Lactobacillus and Prevotella predominating; babies born by Caesarean section present bacterial populations on the skin that are similar to those colonising maternal skin, with Staphylococcus, Corynebacterium and Propionibacterium predominating.6,7

However, these differences disappear during the first month.6

Immediately after birth, the skin microbiota is similar across all sites.5,7 The differentiation of microbes from one site to another arises between 1 to 3 months of life, and skin microbiota composition continues to evolve throughout the first year of life.5,7

The body surface/weight ratio is relatively high at birth, and it gradually decreases throughout childhood; therefore, skin absorption compared to weight will be much higher than it is in adults, and the effects of a toxic substance will potentially be greater as a result.1

All of these factors justify treating the skin of newborns, babies and even infants up to 2 years of age with a specific care routine.2



The first bath: an important moment

Returning home: principles to remember

Bath time

Frequency: Bathing frequency depends on the climate and customs of the family and ethnic group. However, in a temperate climate, a regular bathing frequency of at least 2 to 3 times a week will respect the skin barrier and its adaptation to life outside the womb.9,10

Temperature: 37-37.5°C, measured using a bath thermometer.9-11

Duration: 10 minutes.9,10

Time: The time of day is not especially important.However it is worth noting that a bath given before bedtime has been shown to potentially improve sleep quality.1,9

Washing: Using either the hands or a wash cloth, begin by washing the body, head and hair. The baby's bottom should be washed last.9,11

Cleansing products: Use syndets or high-fat soaps that are free of fragrances, preservatives and dyes, with a pH of between 5 and 6, to wash the body and hair (there is no need to use shampoo on a newborn baby).1,9

Drying: Use a patting motion and avoid rubbing the skin. Take special care while drying the folds of the skin (armpits, neck, elbows, backs of the knees and the groin) to avoid the risk of maceration.9,11

AVOID9:
Alkaline soaps and shower gels, as these can alter the skin barrier, increase pH and lead to dry skin.
Shampoos that contain cocamidpropyl betaine or methylisothiazoline (MIT), due to a risk of sensitisation

Bibliography

  1. Gelmetti C. Skin cleansing in children. JEADV 2001;15 (Suppl. 1) :12–15.
  2. Fluhr J.W., Lachmann N., Baudouin C., et al. Development and organization of human stratum corneum after birth: electron microscopy isotropy score and immunocytochemical corneocyte labelling as epidermal maturation’s markers in infancy. Br J Dermatol. 2014;171:978–86.
  3. Fluhr J.W., Darlenskib R., Lachmannc N., et al. Infant epidermal skin-physiology: Adaptation after birth. Br J Dermatol. 2012;166:483–90.
  4. Merrill L. Prevention, Treatment and Parent Education for Diaper Dermatitis. Nurs Womens Health. 2015 ;19(4):324-36.
  5. Pammi M, O'Brien JL, Ajami NJ, Wong MC, Versalovic J, Petrosino JF (2017) Development of the cutaneous microbiome in the preterm infant: A prospective longitudinal study. PLoS ONE 12(4): e0176669.
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  6. Capone K.A., Dowd S.E., Stamatas G.N., et al. Diversity of the Human Skin Microbiome Early in Life. J Invest Dermatol. 2011;131:2026–32.
  7. Oranges T., Dini V., Romanelli M. Skin Physiology of the Neonate and Infant: Clinical Implications. Adv wound care 2015;4(10):587-95.
  8. Dominguez-Bello M.G., De Jesus-Laboy K.M., Shen N., et al. Partial restoration of the microbiota of cesarean-born infants via vaginal microbial transfer. Nat Med. 2016;22(3): 250–53.
  9. Claudel J-P. L’hygiène du nouvé-né en 5 questions. Dermato Mag 2016.
  10. Blume-Peytavi U., Lavender T., Jenerowicz D., et al. Recommendations from a European Roundtable Meeting on Best Practice Healthy Infant Skin Care. Pediatr Dermatol. 2016;33(3) :311-21.
  11. Collège National des Sages-Femmes. Les bonnes pratiques au cours des premiers jours en maternité. CNFS [French college of midwives] website.
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