S11.lec1 - lactation

Cessation of Lactation

-neural stimulation from suckling promotes prolactin release -cessation of suckling discontinues prolactin release -glandular tissue becomes inactive

Colostrum

a specialized form of milk that delivers essential nutrients and antibodies in a form that the newborn can digest ➢It is lemon colour fluid secretd by the breasts during the first 4_5 days post partum in up to 40 ml/day . ➢ it contains less water soluble vitamins, fat and sugar than later milk, but much more protein, fat soluble vitamins (except vitamine K) & immunoglobulins . ➢ Over the follows 2 - 3 weeks, IgG and total protein declines, whilst fat and sugar rises to produce Mature Milk.

Cracked nipples

fissure a rise of nipple due to poor positioning of the baby on the breast

mastitis

inflammation of the breast

Puerperal fever

is childbirth fever

lobe of mammary gland

lobe contain of many lobules and inside lobulea contain alveoli, alveoli is a site for milk synthesis

alveoli of mammary glands

milk producing glands that are arranged in clusters called lobules myoepithelial cells which is a smooth muscle cell surround the alveoli and responsible for letting milk down

neuroendocrine reflex

when nipple stimulated and suckled by a baby impulse pass through the brain stem and some change happen such as ➢Reduce secretion vaso active intestine peptide (vip) ➢ reduce secretion of dopamine ➢secret oxytocin ➢secret prolactin

The hormonal control of the growth and development of mammary tissues

➢ At birth only a few lactiferous ducts are present, and the breast remains this way until puberty. ➢ At puberty, Oestrogens cause the ducts to sprout 🌱 (budding) and branch and the ends form masses of cells that later become alveoli. ➢ With each menstrual cycle there are changes in breast tissue with changes in the levels of oestrogen and progesterone levels.

some mammary gland components production

➢ Synthesis of milk takes p lace in Alveolar Cells ➢ Fats : Synthesised in Smooth Endoplasmic Reticulum Passes in membrane bound droplets towards the lumen ➢ Protein : Passes through Golgi Apparatus Secreted by exocytosis ➢ Sugar : Synthesised and secreted

let-down reflex

Milk 'let down' is caused by a dramatic increase in the secretion of Oxytocin from the posterior pituitary gland which causes the myoepithelial cells (surrounding the alveoli & lacteferrous ducts) to contract, ejecting the milk. Oxytocin secretion is stimulated by suckling of the nipples by the infant.

Montgomery tubercles

Montgomery's tubercles are sebaceous (oil) glands that appear as small bumps around areola

mamary glands

The mammary gland is a gland located in the breasts of females that is responsible for lactation, or the production of milk. Both males and females have glandular tissue within the breasts; however, in females the glandular tissue begins to develop after puberty in response to estrogen release.

lobe of mammary gland

There is a single lactiferous duct for each of {these} which opens into the nipple. These ducts expand and enter the nipple to form a lactiferous sinus. Each are subdived into lobules which consists of alveoli.

Changes during pregnancy

➢ There is a progressive enlargement of breast size due to proliferation of glands and deposition of fat. ➢There is substantial hypertrophy of the ductular-lobular-alveolar system and prominent lobules form. ➢ The high Progesterone : Oestrogen ratio favours the development of alveoli. Alveolar cells differentiate to be capable of milk productiofrom mid gestation (but not secretion). ➢ Oestrogen causes darkening & enlargement of the nipple & areola and & increase in the number of lactiferous ducts. ➢ Hypertrophied sebaceous glands appear as round elevations _Montgomery's tubercles.

Mature Milk Composition

➢ Water - 90% ➢ Lactose - 7% (Galactose and Glucose disaccharide). ➢Fat - 2% ➢ Proteins (Lactoglobulin (maternal IgG)&Lactalbumin) ➢ Minerals ➢ Vitamins PH around 7

Lactating breast disorders

➢Blood-stained nipple discharge of pregnancy is typically bilateral due to epithelial proliferation. As the condition is self-limiting, no investigation or treatment is necessary, only reassurance. ➢Painful nipples may if the covering epithelium is denuded(removed) or if a fissure develops giving rise to 'cracked nipples'. The cause is usually attributed to poor positioning of the baby on the breast, although thrush (candidiasis) may also cause soreness. Cracked nipples are also associated with an increased risk of a breast abscess developing. Treatment involves resting the affected nipple, Breastfeeding should then be reintroduced gradually

some suckling effect on mother

➢Prolactin secretion also reduces fertility, making a new pregnancy less likely until the infant stops suckling. ➢Another important effect of breast feeding is stimulation of uterine contraction after delivery(oxytocin effect) giving rise to inhibit post partum haemorrhage.

oxytocin release can be stimulated by?

➢Suckling ➢visual sight ➢olfactory stimule ➢auditory stimule such as hearing baby cry 😭 but inhibited by stress

The roughly circular body of the breast rests of a bed that extends from:

➢lateral sternal ridge and mid axillary line ➢between 2nd and 6th rib

breast engorgement is

Breast engorgement is the development of hard, swollen, and painful breasts caused by imbalance between milk production and infants demand. milk produce more than infants suckling, milk accumulate and cause engorgement. Engorged breasts can become extremely large, tight, lumpy, and tender. The swelling may go all the way up into your armpit, and the veins on the surface of your breasts may become more visible or even stick out. ➢Treatment -with analgesia -well fitting bra -continuation of breast feeding. if not treat cause Mastitis & abscess

Turgor

Condition of being distended or swollen; normal fullness