Maternal Health Conditions Cause Low Breast Milk Supply

Certain maternal health conditions can cause low breast milk supply for breastfeeding mothers. 

A couple of years ago, I did a breastfeeding medicine consultation for a new mother. Sally was a health careers student at a local school and was beginning her journey toward a career in medicine. During her training, she and her husband found out that they were pregnant. 

Fast forward to when their baby was 3 weeks old and Sally started to question her decision to breast feed her newborn. As someone who knew about medicine, she was starting to worry that something was wrong. Her breast milk production was not increasing as expected and she needed to give her baby some donor breast milk supplements in order to increase her weight.

As I started working with Sally, I noted how well she handled the baby, how amazing her latch was and listened to the baby suck and swallow at the breast. However, when I moved to the second part of my evaluation, I knew right away what the issue was. 

Unfortunately, Sally's exam was consistent with hypoplastic breast development and insufficient glandular tissue. She knew enough about medicine that she was anticipating this diagnosis. Sally just needed me to say it out loud to her. 

After that discovery, we shifted the focus of the visit to discussing how she could maximize her breast milk supply. I helped her to rethink her breastfeeding goals, and discussed how she could provide nutrition and comfort to her newborn. 

Insufficient glandular tissue is not the only maternal medical condition that leads to low milk supply.

In this article, we will look at ten conditions that can lead to this phenomenon. 

Definition of Low Breast Milk Production

Low breast milk production, also known as insufficient milk supply, refers to the inability of a lactating mother to produce an adequate amount of breast milk to meet her baby's nutritional needs. It is a common concern among breastfeeding mothers. Both newborn and maternal factors contribute to low milk supply. 

While most women are capable of producing enough milk to nourish their infants, certain factors can impact milk production. Mothers and professionals alike need to understand how medical conditions can affect a woman's ability to achieve exclusive breastfeeding. By addressing the underlying health issues and implementing proper breastfeeding management, mothers can work towards increasing their breast milk supply. This enables these women and their infants to enjoy the benefits of breastfeeding. 

Ten Maternal Health Conditions That Cause Low Milk Supply

Low breast milk production can be a consequence of both maternal and infant factors. Often, it can be a combination of many factors. In this article, we will look at ten maternal health conditions that cause low milk supply in breastfeeding mothers. 

Conditions Before or During Pregnancy

1. Maternal Obesity: Women who are obese may have a higher risk of having low breast milk supply. Excess body mass can lead to hormonal imbalances, affecting milk production.

2. Polycystic Ovary Syndrome (PCOS): PCOS is a common hormonal disorder that can cause irregular menstrual cycles and higher levels of androgen hormones. These imbalances may impact milk supply and breastfeeding success.

3. Breast Surgery and/or Breast Cancer: Certain breast surgeries, such as breast reduction or augmentation, can interfere with milk ducts, affecting milk supply. A history of breast cancer also affects a woman's ability to achieve exclusive breastfeeding.

4. Insufficient Glandular Tissue (IGT): IGT is a medical condition where the breast tissue does not develop adequately. This can result in a limited milk supply, making it difficult for mothers to exclusively breastfeed.

5. Hypothyroidism: An underactive thyroid gland can disrupt hormone production, including those involved in milk production. Mothers with hypothyroidism may experience lower milk supply.

6. Insulin Resistance: The interplay between insulin and glucose metabolism has an effect on a woman's ability to produce breast milk. Diabetes and insulin resistance are risk factors for low milk supply. 

7. Hypo-prolactinemia: Prolactin is a hormone that is secreted from the anterior pituitary gland (small pea sized gland at the base of the brain). Prolactin is inhibited by the hormone dopamine. This condition can be due to autoimmune disease, hypopituitarism, and treatment of high prolactin with cabergoline. 

Postpartum Conditions

8. Retained Placenta: The placenta is the organ that maintains your pregnancy. It secretes the hormone progesterone. In the early days of breastfeeding, progesterone can inhibit milk production. Often women with retained placenta will have low milk production in addition to excessive vaginal bleeding.

9. Postpartum hemorrhage: A hemmorrhage after the birth of a child can result in harm to the pituitary gland in the brain. Decreased blood flow to this organ can lead to a condition known as Sheehan syndrome. In this setting, low milk supply is caused by low prolactin levels. 

10. Hypertension (high blood pressure): High blood pressure and more specifically, pregnancy induced high blood pressure or pre-eclampsia is a risk factor for delayed onset of Lactogenesis II or "milk coming in." This often leads to early infant formula supplementation and decreased milk supply. 

Maternal Obesity Can Cause Low Milk Supply 

Maternal obesity can lead to low milk supply for a variety of reasons. The main reason is due to a hormonal imbalance. Adipose tissue (fat tissue) tends to "hold on" to estrogen. This stored estrogen leads to a suppression of the hormones that are necessary for milk production. 

Additionally, women who are obese are at increased risk for other conditions that can lead to low milk supply such as type II diabetes, pre-diabetes (insulin resistance) and hypertension. Some studies have also shown that obese women experience poor milk transfer from the breast to the baby.

Obese women also tend to have a delayed onset of Lactogenesis II or "milk coming in." Babies lose more of their birth weight in the days after birth when lactogenesis II is delayed. This often leads to early infant formula supplementation and worsening of low milk supply. It becomes a vicious cycle that leads obese mothers to quit breastfeeding prematurely or before they intended. 

Polycystic Ovary Syndrome (PCOS)

Polycystic Ovary Syndrome (PCOS) is a hormonal disorder that affects many aspects of a woman's health, including fertility and menstrual cycle regulation. It can also have an impact on breast milk production.

Women with PCOS often have imbalances in their hormonal levels, particularly with regards to insulin and androgens. These hormonal imbalances can interfere with the production and release of prolactin, a key hormone for milk production. Prolactin is responsible for stimulating the mammary glands to produce milk, and any disruption in its levels can lead to insufficient milk supply.

Additionally, PCOS can also affect the development of mammary tissue, making it less responsive to the stimulation of prolactin. This can result in lower milk production and difficulties in successfully breastfeeding.

Breast Cancer, Past or Present Causes Low Milk Supply  

Previous or current breast cancers have a significant impact on breast milk production. Breast cancer and its treatments can interfere with a woman's ability to produce an adequate milk supply.

Women with a history of breast cancer most often do not have sufficient remaining breast tissue left after treatment to produce a full supply of breast milk. On the other hand, women who undergo breast cancer treatment during breastfeeding almost always have to prematurely wean their babies to undergo treatment. 

Breast cancer itself can disrupt breast milk production by causing changes in the breast tissue. Tumors can alter the structure and function of the milk ducts and lobules, making it difficult for milk to be produced and released. Additionally, breast cancer treatments like surgery, radiation therapy, and certain medications can further suppress or damage the breast tissue, leading to reduced milk production.

Radiation therapy, in particular, can harm the breast tissue and affect the functioning of the milk glands. This can result in long-term damage to the milk-producing cells and a decreased milk supply. Similarly, certain chemotherapy drugs can have toxic effects on the breast tissue and the hormone receptors responsible for milk production. Hormonal therapies used to treat breast cancer, such as tamoxifen, can also negatively impact milk supply by blocking the actions of estrogen, a hormone necessary for milk production.

Breast Surgeries

Depending on the reason for surgery, some breast surgeries can interfere with breast milk production while others do not. Often, women who have a breast augmentation or a simple biopsy of a benign breast lesion will not see a significant impact on their ability to breastfeed.

On the other hand, women who have had breast surgery due a history of breast anomalies or surgeries that require cutting of ducts and nerves may experience low milk production. Often unilateral (or one sided) breast surgery prompts me to ask whether or not a breastfeeding mother had surgery due to a congenital abnormality of her breast.

In the setting of one sided breast surgery, women can still produce a full milk supply from just one breast. This of course depends on her medical history, the reason for the surgery and the health of the remaining breast tissue. 

Insulin Resistance 

As we touched on earlier, insulin metabolism is involved in the production of breast milk. It is not well understood exactly how insulin works in this process, but several studies have shown that this hormone involved in glucose metabolism is also involved in human milk synthesis. 

Insulin resistance means that the cells in our body that require insulin in order to move glucose are resistant to its effects. Conditions such as obesity, pre-diabetes and Type II diabetes are all caused by insulin resistance. Milk flow from the breast is based on milk production within the breast. While, we have never proven that insulin has a direct effect on the cells of the breast, we do know that this metabolic process is important. Insufficient milk production can be caused by insulin resistance. 

Prolactin Deficiency or Insufficiency (Hypoprolactinemia)

Prolactin Deficiency or Insufficiency, also known as Hypoprolactinemia, is a maternal health condition that can cause low breast milk production. This hormone is produced by the pituitary gland in the brain and plays a key role in stimulating and maintaining the production of breast milk.

The causes of prolactin deficiency can vary. It may be due to underlying health conditions such as pituitary gland disorders, hypothalamus dysfunction, or hormonal imbalances. Certain medications, excessive stress, or severe malnutrition can also contribute to this condition.

Symptoms of hypoprolactinemia include a slow or inadequate milk supply, difficulty in breastfeeding, and poor weight gain in the baby. Mothers with this condition may experience frustration and emotional distress due to their inability to produce sufficient milk.

Insufficient Glandular Tissue

Insufficient glandular tissue (IGT) is a condition in which the breast does not have enough milk-producing cells or tissues, resulting in a low breast milk supply. IGT occurs when the milk-making tissue of the breast does not develop as expected. This can occur at different stages of breast development.  This includes in utero, during puberty, and/or during pregnancy. There are a variety of causes for this tissue to not develop as expected including endocrine disorders.

Mothers with IGT often have a physical presentation characterized by a wide space between the breasts on the chest wall, tubular shaped breasts with bulbous areolae, and a lack of breast growth during pregnancy.

Sometimes the breast exam is obvious as it was in my opening story, and sometimes it is more subtle.  Another clue is when a breastfeeding mother has a history of breast augmentation whose purpose was to "normalize" the look of the breast. 

Breastfeeding mothers with IGT will often not know that they have it. The diagnosis is often made when lactation fails. With IGT, colostrum changes to mature milk, but then the volume does not increase as it should.

The baby will often experience failure to thrive unless they are supplemented with donor breast milk or formula milk. Exclusive breastfeeding is not possible for mothers with this condition, but inclusive breastfeeding can achieve maternal satisfaction. Lactation consultants and breastfeeding specialists can support mothers with this condition. 

Hypothyroidism Leads to Low Milk Production 

Hypothyroidism, characterized by an underactive thyroid, can lead to low breast milk supply. The thyroid gland produces hormones that are important for the development of mammary tissue and the production of breast milk. When thyroid hormone levels are inadequate, it can result in insufficient milk production.

Additionally, hypothyroidism can affect the composition of breast milk, causing it to have lower levels of key nutrients and hormones necessary for the baby's growth and development.

Postpartum Hemorrhage Leads to Delayed Milk Production 

Postpartum Hemorrhage (PPH) occurs when the uterus fails to contract after childbirth resulting in excessive blood loss. PPH can lead to low milk production because the blood loss causes an inadequate oxygen supply to the pituitary gland. This can inhibit the gland from secreting prolactin and therefore interfere with milk production.

The name of this condition is Sheehan syndrome and it is very rare. For this reason, it is important for women who have experienced postpartum hemorrhage to be monitored for signs of low milk supply.

Retained Placenta

Retained placenta, also known as placental retention, occurs when part or all of the placenta remains in the uterus after childbirth. This can lead to low breast milk production because the retained placenta prevents the release of oxytocin which is essential for the production and release of breast milk.

Additionally, retained placenta can also cause infection or inflammation of the uterus, leading to further disruption in hormone levels and milk supply. Mothers with excessive uterine bleeding and low milk production should seek medical attention immediately. 

Hypertension

Hypertension during pregnancy and postpartum can delay the onset of milk production. As with other conditions that lead to delayed onset of lactogenesis II, this can lead to low milk production. 

Pre-eclampsia is a more serious form of pregnancy induced high blood pressure that can affect many of the mother's organ systems. Often, pre-eclampsia requires magnesium infusion during labor for seizure prevention. This treatment can impact milk supply in several ways. Often, one of the main causes is maternal and baby separation. Babies who are exposed to magnesium during labor.

Concluding Thoughts 

Maternal health conditions are just one category of things that can lead to low breast milk supply in breastfeeding mothers. There are also a whole list of infant factors such as cleft palate, premature birth and Down Syndrome that can also contribute to difficulties in the initiation of breastfeeding and less than adequate milk production. 

Please also remember that even if you have one or more of these conditions, it does not mean that you will absolutely and certainly have low breast milk production. The physiology of breast milk production is complicated and dependent on many factors.

However, pregnant women who have one or more of these conditions need to be proactive and meet with a breastfeeding specialist prior to their baby's birth. A specialist can direct you to the best breastfeeding practices that can improve your breastfeeding experience. Optimizing your health is one of the seven things you can do to prepare for breastfeeding during pregnancy. 

Take heart, all hope is not lost. 

© 127 Pediatrics; October 2023

This article is for informational purposes only and should not be construed as medical advice.

Dr. Andrea Wadley is the owner, pediatrician, and breastfeeding medicine specialist for 127 Pediatrics. She has an established house-calls only pediatric practice in Colleyville, TX. She is also the owner and operator of the 127 Pediatrics Online Breastfeeding Medicine and Education Center.