Nutrition in Lactation

• Nutrition in Lactation

Lactation Definition

• Lactation is the production and secretion of milk by the mammary glands
• Lactation is the act of feeding an infant at the mother's breast

Anatomy of a Lactating Breast

• Terminal Duct Lobular Unit (TDLU) is the functional unit of the mammary gland
• The TDLU consists of a lobule, associated duct, and surrounding stromal tissue
• A lobule surrounds the nipple like spokes on a wheel, comprised of multiple acini
• Acini are small, sac-like secretory units within the mammary gland that produce milk
• Acini are connected to ducts, leading to the nipple
• Acini are of specialized cells surrounded by myoepithelial cells, which help with milk ejection
• Myoepithelial cells are specialized cells that contract in response to oxytocin, squeezing milk into the ducts for expulsion
• Intralobular ducts are small ducts converging to form larger ones, connecting to interlobular ducts
• Interlobular ducts receive milk, transverse stromal tissue, and connect multiple lobules
• Lactiferous ducts are the final link within the ductal system, aiding transport from the TDLU to the nipple
• The nipple is at the center of the areola, composed of 9 collecting milk ducts and thousands of nerve endings
• The areola surrounds the nipple, contains Montgomery glands secreting lubricating oil protecting the nipple and skin

Lactogenesis

• Lactogenesis is the process of producing breastmilk

Stages of Lactogenesis

• Lactogenesis I begins during the last trimester of pregnancy
• Milk begins to form during Lactogenesis I, lactose and protein content increase
• Lactogenesis I extends to a few days postpartum
• Lactogenesis II begins 2-5 days postpartum
• There is increased blood flow to the mammary gland during Lactogenesis II
• The onset of copious milk secretion occurs during Lactogenesis II
• Delayed Lactogenesis II is associated with failure to sustain breastfeeding
• Lactogenesis III begins about 10 days postpartum
• Milk composition is stable during Lactogenesis III

Hormonal Control in Lactation

• Stimulation of the nipple by the baby's suckling initiates action potentials in sensory neurons that connect with the hypothalamus
• In response, the hypothalamus stimulates the posterior pituitary to release oxytocin, and the anterior pituitary to release prolactin
• Oxytocin stimulates milk release from the breast, prolactin stimulates additional milk production

The Different Stages of Human Milk

• Colostrum is thick, yellowish fluid secreted by the mammary gland during the first few days after delivery
• Colostrum delivers 580-700 kcal/L, higher in protein, lower in carbohydrate and fat than mature milk
• Colostrum's major proteins are secretory immunoglobulin A and lactoferrin
• Colostrum has higher concentrations of Na, K, Vitamin E, carotenoids, and chloride than mature milk
• Transitional milk is a combination of colostrum and mature milk
• Transitional milk contains more fat, lactose, and calories than colostrum, needed for growth, energy and nutrients
• Mature milk provides about 70 kcal/100 ml, approximately 1.3g/dl protein in the first month, rising to to 1.5g/dl
• Mature milk has about 78% volume of water

Human Milk vs. Cow's Milk

• Human Milk: 20 kcal/oz or 20 kcal/ 30 ml; Cow's Milk: 20 kcal/oz or per 30 ml
• Human Milk's energy is 6-7% from protein; Cow's Milk's energy is 20% from protein
• Human Milk: 60% whey proteins (mainly lactalbumins) and 40% casein, taurine and cystine in higher concentration; Cow's Milk: 20% whey protein and 30% casein, taurine and cystine present in lower concentration
• Human Milk has provides 42% of energy with Lactose, Cow's Milk 30%
• Lipids in Human Milk provides 50% of the energy with 4% linoleic acid and 10-20 mg/dl cholesterol; Lipids in Cow's milk provides 50% of energy with 1% linoleic acid and 10-25 mg/dl cholesterol
• Vitamin content in human milk is reflective of maternal intake, adequate, and richer source; Vitamin content in cow's milk contains B-complex vitamins, is adequate for supplemented, and less rich source
• Human milk has small amounts (0.3 mg/L) of minerals, about 50% is absorbed, higher bioavailability and lower Ca, P, & Fl content when compared to cow's milk
• Cow milk has small amounts (0.3 mg/L) of iron, less than 1% is absorbed, lower bioavailability, higher Ca, P, & Fl content

Procedures for Breastfeeding

• Initiate skin-to-skin contact right after delivery, holding the baby naked against mother's skin
• This helps regulate baby's temperature, breathing and heart rate, stimulates feeding, bonding, and immunity to infections
• Start breastfeeding within 20-30 minutes after birth to improve lactation success
• Wash hands before and after breastfeeding
• Rub a small amount of breast milk into your nipples after breastfeeding and let it dry in the air
• Keep nipples clean and dry, change breast pads often
• Avoid use of breast pads with plastic on the back
• Wear loose clothing in a breathable fabric such as cotton, avoid wearing padded bras

Breastfeeding Positions

• Cradle hold is classic, with the baby's stomach against the woman's body, supported by the arm on the same side as the nursing breast
• Cross-cradle is similar to cradle, but the woman supports the baby with the arm opposite the feeding breast
• This hold is typically for newborns, and can be helpful for babies who typically struggle with latching
• Clutch/Underarm hold or rugby ball hold is ideal after abdominal surgery, dealing with pain after childbirth, or nursing two babies simulataneously
• The baby is in face-up position, held close to the side
• Laid Back hold/Reclined/Biological Nursing stimulates a baby's instinctive feeding reflexes, is comfortable for both baby and mother
• Koala hold is good for older babies or an overactive letdown
• Side-Lying Position is an ideal breastfeeding position for women recovering from surgery, and for exhausted women feeding at night

Frequency of Breastfeeding: Cues of Hunger and Satiety

• Rooting reflex indicates hunger; the infant turns head from side to side with mouth open responding to touch
• Non-nutritive suck is quick and not rhythmic; the beginning of feeding
• Foremilk, secreted at the beginning of breastfeeding, is watery, high in lactose for quick hydration and energy
• Nutritive suck is slower and rhythmic
• Hindmilk, secreted at the end of feeding, is thicker, creamier, higher in fat and calories to satisfy the baby and promote growth

Frequency of Breastfeeding

• Stomach empties in 1 ½ hours
• Feed newborns 10-12 times per day
• Feed baby until the baby stops feeding, or can keep awake by tickling the feet, rubbing the head, and talking to the baby
• Some infants don't feed from mid-night until early morning, so consume more milk in the other feedings
• During feeding, milk intake and weight gain were similar whether the feedings were distributed over 24 hours or not

Duration of Breastfeeding: 1,000 Days of Life

• Breastfeeding should be between a mother's pregnancy and her child's second birthday, per the "golden window of opportunity"
• Exclusive breastfeeding occurs up to the 6th month and complementary feeding to the second birthday of the baby

Benefits of Breastfeeding

• Benefits for mothers: quick recovery from childbirth, delayed return of regular ovulation, conserves iron stores
• Benefits for infants: provision of appropriate composition and balance of nutrients, hormones that promote physiological development, protection against a variety of infections and illnesses, protection against chronic diseases

Contraindications of Breastfeeding

• Infant with galactosemia, a rare genetic disorder, cannot metabolize galactose
• Mothers with active tuberculosis, due to the risk of transmission through droplet infection
• Mothers with human T-cell lymphotropic virus type 1 and 2, a retrovirus that can cause severe illnesses, transmitted through breastfeeding
• Tobacco and caffeine intake pass into breast milk, leading to baby fussiness, nausea, restlessness, even impacting sleep patterns
• Frequent consumption of large fishes like shark, swordfish, bigeye tuna, king mackerel and tilefish cause neurotoxic effects in infants and children, due to high levels of mercury
• Consumption of Drugs of abuse and alcoholic beverages affect the baby's growth, development, and sleep
• Mothers with HIV who were not on antiretroviral therapy transmit the virus to their infants

Breastfeeding Difficulties and Management

• Inverted nipples: use breast shells, roll nipple to make erect
• Breast engorgement: massage breasts, express milk, use cool compress or raw cabbage leaves
• Poor latch: proper positioning, mouth-full, use nipple shield as last resort
• Baby's mouth not open wide enough: depress lower jaw, elicit wide-open mouth from baby
• Sore nipples: assess pain, proper latch, hand express milk and air dry, approved nipple ointment
• Baby Sucks poorly: use massage, stimulate the sucking motions Baby demonstrates rooting but does not grasp the nipple: comfort, allow time to relax, express milk
• Baby falls asleep: stimulate by skin to skin, rubbing baby back, talking
• Plugged Ducts: Massage the area, moist heat compresses ,Lecithin supplement may help to prevent reoccurrence
• Mastitis: antibiotic medications, continue breastfeed

Lactation Nutrition

• Calories: add 500 kcal to your daily diet to support milk production
• Protein: add 27 g daily for amino acid synthesis, prolactin levels, and tissue-repair maintenance
• Water: add 700mL daily to account for breast milk composition of 87% water
• Vitamin A: add 400 mcgRE to ensure adequate vitamin A levels in breast milk
• Folate: add 150 mcgDFE for growth and development
• Vitamin C: add 35 mg for supporting the mother's health, and providing this essential nutrient to the baby
• Iron: add 2 mg. to replenish iron lost during pregnancy and birth
• Zinc: add 7 mg for infant growth, development, and immune production, essential for infant growth, development, and immune function
• Iodine: add 100 mcg so breastfed infants can depend on you. for their thyroid hormone synthesis
• Magnesium 50 mg for muscle relaxation and nerve function
• Vitamin B6: add 0.7 mg for support in the mother, and baby development
• Thiamin: add 0.2 mg to prevent thiamine deficiencies in breastfed infants
• Vitamin B12: add 0.5 mcg for infant's brain development and blood cell production; lactation can deplete maternal stores
• Niacin: 3 mgNe breastfeeding requires a significant amount of energy for milk production

Lactation Nutrition: Breastfeeding and Weight Loss

• A gradual weight loss is safe but remember not to cut below 1,800 kcal
• Stress can decrease the amount of milk
• Moderate-intensity physical activity is good
• Breastfeeding burns about 500-700 kcal a day

Philippine Policies and Programs Supporting Breastfeeding

• Philippine Code of Marketing of Breast-milk Substitutes, (Executive Order 51, 1986)
• Rooming-In and Breastfeeding Act (Republic Act 7600, 1992)
• Expanded Breastfeeding Promotion Act (Republic Act 10028, 2010)
• Republic Act 11148 Mag-Nanay Act of 2018