FISIOLOGI LAKTASI

Summary

In this educational video, Erli Zainal, a lecturer at Stikes Sapta Bakti Bengkulu, explains the complex physiology of lactation. The video covers key stages of lactation, including mammogenesis, lactogenesis stages 1 and 2, and the role of hormones like prolactin, estrogen, and progesterone. It also delves into the anatomy of the breast and how breast tissue develops during puberty and pregnancy. The video further highlights the process of milk production, from the initial stages in pregnancy to the production of colostrum and mature milk post-birth, providing vital information about breastfeeding physiology and its essential nutrients for infant health.

Takeaways

• 😀 Lactation is a complex physiological process that begins before childbirth and involves various hormonal and anatomical changes.
• 😀 Lactogenesis, the process of milk production, occurs in two stages: initiation (Stage 1) and activation (Stage 2).
• 😀 During Stage 1 of lactogenesis (initiated around the 16th week of pregnancy), hormonal changes prepare the breast for milk production, but milk release is suppressed until after childbirth.
• 😀 Stage 2 of lactogenesis begins after childbirth when progesterone and estrogen levels drop, and prolactin takes over to stimulate milk production.
• 😀 Colostrum, a yellowish fluid produced initially after birth, is rich in antibodies and vital for the newborn's immune system.
• 😀 The structure of the breast includes alveoli, which produce milk, and ducts that transport milk to the nipple.
• 😀 The breast has 15-20 lobes, each with a duct system that carries milk from the alveoli to the nipple.
• 😀 Milk composition includes fats, proteins (60% whey, 40% casein), carbohydrates (mainly lactose), and important vitamins and micronutrients.
• 😀 Breast milk contains immunoglobulins (IgA, IgG, IgM), which provide protection against infections and help prevent allergies.
• 😀 Vitamin D in breast milk is typically insufficient for bone health, so supplementation may be necessary for the baby.
• 😀 Understanding lactation physiology is essential for ensuring successful breastfeeding and optimal health for both mother and child.

Q & A

What is lactation physiology and why is it considered a complex process?

Lactation physiology refers to the process of milk production and secretion from the mammary glands. It is considered complex because it involves multiple physiological changes starting before childbirth and continuing after birth, including hormonal shifts and changes in breast tissue during puberty, pregnancy, and lactation.

How does the body prepare for lactation during pregnancy?

During pregnancy, hormonal changes, including increased levels of prolactin, human placental lactogen (HPL), estrogen, and progesterone, trigger the mammary glands to prepare for milk production. These hormones stimulate the growth of glandular tissue and the development of milk-producing cells.

What is the role of the breasts in lactation?

The breasts consist of alveoli, which are small, grape-like sacs that produce and store milk. These alveoli are surrounded by myoepithelial cells that help expel milk. A group of alveoli forms a lobule, which connects to milk ducts. Each breast has 15-20 lobules, and the ducts carry milk from the alveoli to the nipple for feeding the infant.

What is lactogenesis, and what are its two stages?

Lactogenesis is the process by which the mammary glands develop the ability to secrete milk. It occurs in two stages: Stage 1 (initiation of secretory activity) begins around the 16th week of pregnancy, preparing the glands for milk production, but milk secretion is inhibited by high progesterone levels. Stage 2 (activation of secretory activity) occurs after birth when estrogen and progesterone levels drop, allowing prolactin to initiate actual milk production.

Why do breasts not release milk during pregnancy despite the development of mammary glands?

During pregnancy, despite the preparation of mammary glands for milk production, high levels of progesterone inhibit milk secretion. Milk may occasionally leak in small amounts, but full milk release only occurs after childbirth when progesterone levels drop.

What is colostrum, and why is it important for the newborn?

Colostrum is the early milk produced by the mother after birth. It is a yellowish liquid rich in antibodies and immune cells, providing vital protection against infections. Colostrum also helps the baby pass its first stool (meconium) and has a laxative effect, facilitating this process.

How does the composition of breast milk change after birth?

After birth, breast milk undergoes changes in composition. Initially, the milk is low in fat (colostrum), but over the first few days, the milk's fat content increases. This increase in fat content occurs as the milk moves through the ducts and as the baby continues to suckle, stimulating milk production and altering its nutritional profile.

What are the key nutrients found in breast milk, and why are they important?

Breast milk contains essential nutrients, including vitamins, micronutrients, lactose, and proteins such as whey (60%) and casein (40%). The proteins include immunoglobulins (IgA, IgG, IgM), which play a critical role in protecting the baby from infections, and reducing the risk of allergies. However, breast milk is typically not sufficient in vitamin D, so supplementation is often recommended.

What is the role of the areola in breastfeeding?

The areola, the dark area around the nipple, plays a crucial role in breastfeeding by secreting a fluid that moisturizes and protects the nipple during suckling. It also contains Montgomery glands, which are visible as bumps and secrete oil to keep the nipple area lubricated and prevent cracking.

How does milk fat content vary during a breastfeeding session?

During a breastfeeding session, the fat content of milk increases as the baby continues to nurse. Initially, the milk in the ducts has a lower fat content, but as the baby sucks more, the milk that enters the ducts has higher fat content, providing more calories and nutrients.