91 Lactation Flashcards
What is lactation?
Secretion of milk by breasts (mammary glands)
What is the colostrum?
First milk produced
What is the recommendation for breast feeding?
Exclusively for first 6 months for optimal lifetime benefits
Benefits of breast feeding for baby?
- Reduced incidence of GI, respiratory and middle ear infection
- Decreased risk of childhood diabetes, asthma and eczema
- Reduced risk of lactose intolerance
- Improved intellectual and motor development
- Decreased risk of obesity in later life
- Possible reduced autoimmune diseases
- 27% reduced risk of sudden infant death syndrome
Benefits of breast feeding for mother?
- Promotes recovery from childbirth
- Promotes return to ‘normal’ body weight
- Promotes a period of infertility
- Reduces risk of premenopausal breast cancer
- Reduces risk of ovarian cancer
- Possibly improves bone mineralisation
Role of prolactin in lactational amenorrhoea?
• Prolactin suppresses hypothalamic release of GnRH and therefore pituitary FSH and LH
=> Prevents follicular growth, ovulation and menstruation
• Women who exclusively breast feed their baby will delay the onset of menstrual cycles
Lactational amenorrhoea method (LAM) is effective so long as:
- Must be ammenorrhoeic
- Baby must be exclusively breast fed
- Baby < 6 months old
Breast structure at birth?
Breast consists of lactiferous ducts without any alveoli
Changes to breast at puberty?
- Under influence of oestrogen the ducts proliferate and masses of alveoli form at the ends of the branches
- Each cycle involves proliferative changes in the alveoli and there may be secretory activity
Changes to breasts during pregnancy?
- Under the influence of oestrogen, progesterone and prolactin the glandular portion of the breast undergoes hypertrophy replacing adipose tissue
- From week 16 the breast tissue is fully developed for lactation but is quiescent awaiting activation
- After parturition the breast produces colostrum before mature milk production begins
Breast alveoli development?
- Prior to pregnancy, ducts with few alveoli exist
- In early pregnancy, alveoli grow
- In mid pregnancy, alveoli enlarge and acquire lumen
- During lactation the alveoli dilate
- After weaning, gland regresses
Pathways of alveoli (modified sebaceous glands) emptying in breast?
Via lactiferous ducts that are dilated to form lactiferous sinuses which open on the surface of the nipple
Tissue change in pregnant breast?
- Adipose tissue is dominant in non-lactating breast
* Glandular tissue only develops fully during pregnancy
What are the secretory alveoli/ acini - the milk producing cells, stimulated by?
Prolactin
What is each alveolus surrounded by? Stimulated by?
- Each alveolus surrounded by contractile myo-epihtelial cells
- Stimulated by oxytocin
What happens to the fat in lactating breast?
Replaced by glandular tissue