Breast Changes & Lactation

Overview

Dr. Rayan Albarakati
MBBS, SB-OB
Majmaah University
Assistant Professor

Objectives

Identify the normal physiologic & anatomic changes of breasts during pregnancy and postpartum.
Define colostrum.
Describe the differences between colostrum and human breast milk.
Describe how to treat common postpartum abnormalities of the breast.
Identify the advantages of breast-feeding.
Describe common challenges in the initiation and maintenance of lactation.

Physiologic & Anatomic Changes of Breast

The breasts gland, tissue, and nipples increase in size, areola color darkens, and some veins under the skin might become visible.
Estrogen, progesterone, human chorionic gonadotropin, cortisol, insulin, prolactin, and placental lactogen all play an important role in preparing the breasts for lactation.

Anatomical Changes

Breast

Hypertrophy (asymmetrical)
Stretch marks
Sore or tender
Visible veins
Lumps & bumps
Points downwards

Nipples

Darkens
Widens
Montgomery tubercles hypertrophy
Pronounced & elongated
Leaks

Breast Lobule Maturation During First Pregnancy

The image illustrates the changes in breast anatomy during different stages of a woman’s life, particularly focusing on the maturation of breast lobules during the first pregnancy.

Breast Changes Across Different Life Stages

Early Childhood (1-10 years old)
Puberty
Early Pregnancy

Comparison of Breast Lobules

Before Pregnancy
- Lobule
- Enlarged lobule
During Pregnancy
- New lobule

Stages of Breast Lobule Maturation

After puberty before pregnancy
End of 1st Trimester
End of 3rd Trimester
After weaning

Physiologic Changes

Estrogen and progesterone prepare breasts to make milk. *Released by the placenta during pregnancy.

They have two major roles:

They increase the size and number of milk ducts.
They suppress the body from making large amounts of breast milk until after the baby is born.

Once the baby is born and the placenta is delivered, these hormones decrease. This decrease signals the body that it is time to make milk.

Lactating Breast

Full of Milk

Cooper’s Ligaments
Ribs
Muscle
Fat
Ducts
Glandular Tissue (alveoli)
Nipple
Areola

Role of Prolactin

Prolactin helps breasts make milk.
After the birth, prolactin levels increase.
With suckling prolactin is released.
With each release, the body produces and stores more milk in the breast alveoli.
If the level of this hormone gets too low, milk supply will decrease.

This is why it is important to breastfeed or pump right after delivery and then at regular time frames.

Oxytocin

Releases milk from breasts.
Suckling releases this hormone. This release causes milk to be squeezed out of the alveoli, into the ducts, and out.
This process is called Milk Ejection Reflex (MER).

Milk Ejection Reflex (MER)

Alveoli full of milk (pre-MER)
Alveoli releasing milk into ducts (post-MER)

Initiating Lactation

At delivery, two events are essential in initiating lactation:

A drop in placental hormones, particularly estrogen.
Suckling stimulates the release of prolactin and oxytocin.
- Oxytocin causes contraction of the myoepithelial cells in the alveoli and milk ducts (ejection).
- Prolactin promotes the production of milk in breast alveoli.

Hormone Levels of LactationZ

Colostrum Definition

A form of milk which is the first secretion from the mammary glands after giving birth, rich in antibodies, and yellowish in color.

Colostrum & Breast Milk

Colostrum is secreted 2^nd day after delivery for 3-6 days.
It is the colostrum that contains secretory IgA.
The major components of breast milk are proteins, lactose, water, minerals, and fat.
The major proteins synthesized exclusively in human breast milk are casein, lactalbumin, and ß-lactoglobulin.

COLOSTRUM & MILK PRODUCTION (approximate times)

	Pregnancy	Birth	Postpartum
	2nd trimester	3rd trimester	Birth	Postpartum days 2-4	Postpartum days 5-14	Postpartum day 14+
Colostrum	X	X	X	X
Transitional Milk				X	X
Mature Milk						X

Colostrum and Transitional Milk

Improves immune function.
Promotes gut maturation.

Colostrum	Transitional Milk	Mature Milk
Pre-milk fluid
Rich in immunoglobulins and immune cells, growth factors	Higher levels of fat, protein, sodium, Cl, Ca++, Zn, Cu, folate, lactose, and vitamins compared to term milk	Less concentrated, lower nutrient density maintained throughout the first postpartum year
First 24 – 48 hours postpartum Day 1 6 – 10 mL/kg/d Day 2 13 – 25 mL/kg/d	3rd – 14th day postpartum	2 weeks postpartum

Comparison of Breast Milk ContentsZ

MACRONUTRIENT (PER100ML)	COLOSTRUM	MATURE MILK
Energy	58 Kcal	58-72 Kcal
Total Protein	2.3 g	0.9 g
IgA	364 mg	142 mg
Casein	140 mg	187 mg
Lactoferrin	330 mg	167 mg
Lactalbumin	218 mg	161 mg
Total Fat	2.9 g	4.2 g
Lactose	5.3 g	7.0 g
Cholesterol	27 mg	16 mg

Advantages of Breastfeeding

There are many advantages to breastfeeding:
1. Breast milk is the ideal food for the newborn, is inexpensive, and is usually in good supply.
2. It provides the newborn with passive immunity (secretory immunoglobulin A and maternal lymphocytes).
3. It accelerates the involution of the uterus because suckling stimulates the release of oxytocin.
4. Emotional Bonding between the mom and the newborn.

Challenges of Initiation and Maintaining Breastfeeding

No Milk is coming.
Baby in NICU.
Mother uses certain medications.
Mother is working and not with the baby all the time.
Breast pain.
Cosmetic reasons.

Common Postpartum Breast Complications & Management

Engorgement & Pain (most common)
Cracked nipples
Mastitis
Galactocele or Plugged ducts
Breast abscess (0.5%)

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