Breast development begins before you are even born. It continues through several stages during puberty, childbearing years, and beyond. In fact, breasts never stop changing. Hormones signal changes during puberty, pregnancy, and after the baby is born for an intricate system inside the breast for milk storage and transport to be able to feed your baby. Breast changes during pregnancy do not always determine the milk supply after the baby arrives. All breasts are unique in size and shape. 

Myth:

Having small A-cup breasts does not predict that you will have a low milk supply, just like having large breasts doesn’t mean you will have lots and lots of milk. 

Fact:

Milk production is based on your anatomy, including the development of your breast’s ductal system and nerve pathways, milk storage capacity, hormones, and hormone receptors, and effective and frequent milk removal.

1. Pre-glandular - reduced supply is caused by hormone imbalances caused by a retained placenta after delivery or postpartum thyroiditis.
2. Glandular - could be due to a prior breast surgery that severed mammary ducts or nerves or hypoplasia/IGT (Insufficient glandular tissue).  Often, pre-glandular or post-glandular markers will also contribute to the picture.
3. Post-glandular - when breastfeeding got off to a tough start or issues with the baby being able to transfer milk well due to oral restrictions, birth trauma, or other complications. Separation from your baby after birth and other breastfeeding management factors like scheduled feeds, the introduction of supplements, early pacifier use, and sleep training can negatively affect milk supply.

In utero, breasts begin to form along the mammary ridge on the chest. By birth, nipples have formed, and the beginnings of a ductal system are in place. 

Puberty, driven by the ovaries releasing estrogen, causes breasts to grow as fat builds up, and the ductal system grows as glands form at the end of the milk ducts. (1) As puberty continues, with the release of estrogen in the first half of the menstrual cycle, more lobules and ducts grow, followed by the second half of the menstrual cycle when progesterone stimulates the formation of milk glands. 

Pregnancy & birth trigger the lactation process. During pregnancy, starting around 16 weeks, your hormones send the message for milk ducts to multiply. (2) Changes to your areola and breast size and appearance happen during pregnancy and after you deliver your baby and the placenta. 

Alveoli are small sacs that make and store milk. Clusters of alveoli, which make up a lobe, are called lobules. Each lobe is connected to a duct. Ducts are a network for milk to flow through toward the nipple when a baby begins to suck. There are lots of sensitive nerve endings in the areola. When they are stimulated by your baby sucking, hand expression, or pumping, oxytocin is released, and milk flows. Prolactin is also released, which sends the message to make more milk as it is removed. Damage to the nerves can affect sensation, milk release, and milk production.

Hypoplasia is a condition in which a person’s glandular tissue develops differently. It is characterized by breast shape, distance between each breast, and symmetry. Not all people with hypoplasia have a lowered milk supply, but it is more common. Management techniques can help increase supply. If you have hypoplasia/IGT, you can still have a satisfying nursing relationship with your baby. (3)

• Normal-sized breasts that lack a sufficient amount of glandular tissue can result in a reduced milk supply
• Breasts are widely spaced apart
• One breast is much larger than the other - breast asymmetry
• Breasts have stretch marks without them growing larger. This may appear during puberty or pregnancy.
• Breasts are tubular-shaped
• Areola has a swelled or bulbous appearance and is large compared to breast size
• No noticeable changes to breast size or feelings of fullness during pregnancy or postpartum
• No noticeable veining in the breasts increasing during pregnancy

Hormones play an essential role in glandular development, milk production, and supply.  Polycystic Ovarian Syndrome (PCOS) and insulin resistance sometimes accompany IGT. Not everyone with PCOS and insulin resistance has IGT and may develop sufficient glandular tissue and have a full milk supply. 

Black cumin seed is a powerful hormone-balancing herb that regulates thyroid hormones, raising T3 and T4 while lowering TSH. (5) People who have previously experienced issues with low supply, have a history of PCOS, insulin resistance, or hypothyroidism may find Black Cumin seed helpful when trying to increase their milk supply. 

Legendairy Milk’s lactation supplement with black cumin seed:

• Pump Princess

Goat’s rue contains a compound called genistein, which has been shown to increase breast tissue and milk storage capacity. People who did not experience growth of their breasts during pregnancy and those who had a rocky start and their milk storage decreased, reducing supply, can benefit from Goat’s rue. 

Legendairy Milk’s lactation supplements with Goat’s rue: 

• Lechita
• Liquid Gold 
• Cash Cow 

After the baby is born, skin-to-skin contact benefits the mom and baby and gives them a good start to nursing. Interruptions and separation from each other interfere with how often the baby nurses. Frequent and effective milk removal will send the signal to keep making milk.

Using a supplementer at the chest is a popular tool where all feeding occurs at the breast. The baby will get all of the mom’s milk while feeding and any additional milk needed from donor milk or formula in the supplementer bag. One end of the tube is connected to the supplementer system, and the other end of the tube is placed near the nipple and goes in the baby’s mouth as they nurse. 

Breastfeeding is partly about milk for your baby, but there is so much more to a breastfeeding relationship that can be enjoyed regardless of IGT. When hormone issues and breastfeeding management are being addressed, and supply is still low, IGT may be the resulting diagnosis. 

Your feelings are important. When IGT interferes with breastfeeding, talk with others who have had similar experiences and allow yourself to grieve the loss of your expectations of what you imagined the breastfeeding relationship with your baby would be. Work with a knowledgeable IBCLC who listens to you and helps you create a plan for a long and satisfying breastfeeding relationship between you and your baby.

Breast development involves various stages and hormonal changes. The size and shape of your breasts do not determine your milk supply. Several factors influence milk production, including your anatomy, hormone receptors, and effective milk removal. Hypoplasia and IGT can affect milk supply, but with proper management techniques and support, you can provide your milk for your baby along with any necessary supplement if you are not making a full supply. Breastfeeding may look different than expected, but it can still be a beautiful and fulfilling experience for you and your baby.

1. https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=90&contentid=P01624
2. https://my.clevelandclinic.org/health/body/22201-lactation#:~:text=Human%20milk%20comes%20from%20your,lobule%20connects%20to%20a%20lobe.
3. https://pubmed.ncbi.nlm.nih.gov/4058994/
4. https://kellymom.com/bf/got-milk/supply-worries/insufficient-glandular-tissue/
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5767798/

https://jag.journalagent.com/ias/pdfs/IAS_21_1_19_28.pdf

https://kellymom.com/bf/got-milk/supply-worries/insufficient-glandular-tissue/