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Bilirubin and Lactation

Baby Toes

What is bilirubin?

Bilirubin is a yellow pigment produced by the breakdown of red blood cells in our blood. Our body, particularly the liver, is responsible for taking this and other pigments and metabolizing them, breaking them down into smaller molecules that are easily transported throughout the body.


What is jaundice?

Usually, the first sign that leads us to suspect elevated levels of bilirubin in a newborn is the color of the skin. The skin turns somewhat yellow, and in some cases, the sclera (white part of the eye) can also appear yellowish. This is known as jaundice. Jaundice can appear within the first 48 hours of life and can last for several weeks, even months, after birth. It should be evaluated to determine its cause and provide the necessary attention.


According to the Academy of Breastfeeding Medicine (ABM), almost all newborns have some degree of elevated bilirubin levels, attributed to three main factors:


1. Increased bilirubin production due to the high breakdown of red blood cells after birth.


2. Inability to capture and metabolize bilirubin due to the liver's immaturity to perform these functions.


3. Increased reabsorption of bilirubin in the intestine (more bilirubin returns to the blood, and less is excreted).


All of the above are known as physiological causes (biological response).


Physiological jaundice occurs on the second or third day of life, with levels peaking on the third day and resolving by the fifth day after birth. Usually, the levels increase by less than 5mg/dL per day.


Jaundice can also occur in liver diseases, metabolic disorders, hematological conditions such as anemia, infections, and sepsis, among many others.


Jaundice that occurs within the first 24 hours of birth is known as pathological jaundice, and levels can increase by more than 5mg/dL per day. It should be evaluated because the accumulation, both in the body and the brain, can have devastating effects.


In the case of physiological jaundice, which occurs in the first few days, it is important to determine if the baby is breastfeeding or chestfeeding with human milk or formula. In this text, we will delve into jaundice related to human milk.


Newborns exclusively breastfed or chestfed who present elevated bilirubin levels must be evaluated to determine if they have a good latch and are effectively extracting milk. Just because a baby is at the breast and nursing does not mean they are truly extracting and taking milk.


Newborns fed with formula during the first few days of life typically do not present jaundice because they tend to consume much larger amounts of milk than those fed at the breast or chest only. The notion is that not having jaundice is normal. On the contrary, breastfeeding or chestfeeding with human milk is natural, and as such, natural and physiological presentations occur in newborns fed this way.


This type of jaundice is divided into two categories related to weight; according to the ABM, these categories are:


  • Jaundice associated with inadequate intake of human milk: It occurs in the first week of life. It presents with weight loss, less than 5 dirty diapers a day (black, brown, or green), and fewer than 5 wet diapers a day, some of them brick-colored. It resolves once the baby starts consuming enough milk (1-2 weeks).

  • Jaundice due to human milk or Breast or Chest Milk Jaundice Syndrome: Its cause is unknown, although there are different theories. It occurs in the first week of life, persists even after substantial weight gain in a newborn who is exclusively breastfed or chestfed. The baby has more than 8 dirty diapers a day, yellow in color, and more than 8 wet diapers a day, yellow or transparent. It could last up to 3 months. However, it must be evaluated to rule out other conditions.


Renowned doctor Jack Newman states that in these cases, breastfeeding or chestfeeding should rarely be discontinued, and it should not be stopped to reach a diagnosis. In fact, a baby who is growing and developing healthily with only human milk should not stop breastfeeding or chestfeeding or be supplemented, even if it is given as an aid to breastfeeding or chestfeeding.


How is jaundice related to human milk resolved?

The response to this situation lies in helping these families achieve effective and successful breastfeeding or chestfeeding. In most cases, jaundice in a newborn who is breastfed or chestfed is a natural biological response. Breastfeeding or chestfeeding should not be interrupted; instead, the initial management should be an evaluation of the latch to ensure it is adequate for effective milk extraction, rather than immediately resorting to supplementing with formula or sugar water. The latter is actually contraindicated since studies have shown that supplementing with sugar water does NOT decrease bilirubin levels and can interfere with breastfeeding or chestfeeding and even cause hyponatremia (low blood sodium). These actions should be taken in conjunction with an evaluation for pathological conditions if suspicion arises.


Another therapy used is phototherapy (using special blue spectrum lights) as a treatment for jaundice, reserved for cases where bilirubin is rapidly increasing above standard levels. The famous sunbaths as a treatment only work if the newborn receives sunlight without clothes. This exposure to sunlight is dangerous when not filtered as it does not protect the skin from UV rays. This could lead to burns, increased body temperature, dehydration, and an increased risk of skin cancer. Sun phototherapy can be effective under controlled conditions and is a great ally in developing countries when special equipment is not available or in emergency situations where there is no electricity. One way to filter sunlight for phototherapy is by using special dyes and curtains capable of filtering harmful rays and allowing the passage of therapeutic rays.

During phototherapy, breastfeeding or chestfeeding should not be interrupted. If the baby is not breastfeeding or chestfeeding vigorously or is too sleepy to do so, it is recommended that the breastfeeding or chestfeeding person express their milk and then offer it with a syringe, cup, or bottle. If necessary, supplementation can be done with donated human milk, and if it is not available, formula can be used.


Written by: Dr. Michelle Lozada Martínez.



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