Lactation 2

Question 1

The Stages of Lactation: stage 1

Answer 1

Lactogenesis Stage I: preperation

• Mid gestation to day 2 postportum (breast capable from mid gestation but lactation doesn’t usually occur to post-partuition)
• Withdrawal of the Placental steroids is responsible; as this removes the inhibitory affect of E₂ and P₄ on breast response to prolactin

Question 2

The Stages of Lactation: stage 2

Answer 2

Lactogenesis Stage II: start of larger-scale milk production

• PostPartuition days 3-8 first week
• Changes in Milk composition: Increase a-lactalbumin; decreased sodium and chloride in milk (less salt)
• Due to tight junctions in alveolar epithelium stopping salt getting through

Question 3

The stages of Lactation: Glactopoiesis

Answer 3

Maintainence of established milk secretion, main phase of large scale milk production

Question 4

The stages of Lactation: Involution

Answer 4

Approx 40 days after last feed; due to buildup of inhibiting substances, loss of prolactin secretion as no longer stimulated

Question 5

The stages of lactation: Summarised

Answer 5

1. Lactogenesis I: preperation
2. Lactogenesis II: start of production
3. Glactopoiesis: milk production
4. Involution: stopping

Question 6

What is the milk produced initially called, and how is it different to mature milk?

What is its very special purpose?!

Answer 6

Thick product called Colostrum

• Contains less sugar and less fat (less energy focus) then mature milk
• Colostrum contains more total protein and is rich in Antibodies, especially IgA
  
  • IgA is the immunoglobulin of your secretory immune system: link between GALT (gastric assoc. lymphoid tissue) and MALT (mammary assoc. lymphoid tissue) so when mums being exposed to something in gut, she produces an immune response mediated by IgA of secretory IS, will also be product in mammary glands → Antibodies transferred to baby and protecting them again organisms mums exposed to
  • This is essential to buiding the babies immune system which is poorly developed at birth

Question 7

Whats in Human Milk?

Draw out the full table of components and their functions

Answer 7

These components all work together to not just feed the baby but to protect it from pathogenic advances!

Question 8

What are the difference between Bovine and human milk?

Answer 8

• Humans take 4-6 months to double birth weight; most mammals do this quickly
• Therefore this tells us human milk must be specifically adapted for humans!

Lactose: for energy and melin production (we have 1.5x more0

• *Casein**: major protein
• *a-Lactalbumin**: part of the enzyme that produces lactose synthesis by promoting activty of galactocidal transferase enzyme (we have more)

Linoleic Acid: essential fatty acid that must be present in the diet (we have more)

Question 9

Why is it important to know there’s a significant difference between bovine and human milk?

Answer 9

Because formula is dervied from cow’s milk, so we need to realise no matter how much we modify it it’s not the same as being breast feed!

Question 10

DOes size affect milk production?

Answer 10

No, it doesn’t affect milk production capacity (that’s dependent of PRL), but larger breasts do have a greater capacity for milk storage.

This storage capacity can be different for each breast (right Boob usually better)

Question 11

What are the personal benefits of breasting feed for mum?

Answer 11

1. Spacing of offspring
   
   • exclusive BF for 6 months → lactational amenorrhea
   • May also → weight loss
2. Bonding to offspring
   
   • eye contact
3. enhances involution of the uterus
   
   • ​500-600 micron long myoepithelial cells need to shrink back to normal size
4. Protects against Type II Diabetes
5. Protects against Post-partum depression
6. Protects against breast cancer and ovarian cancer (if BF >12 months)

Question 12

A metaanalysis is???

Answer 12

Expert Review: expert in their field writes down balanced view of literature

Systematic Review: set up a set of rules, go out and search the lliterature via those unbiased set of rules. Gathers all available published evidence and uses only the relevant ones.

• THEN wise man sits down and reviews
• This is what evidence based medicine is based on

Then a Metaanalysis of the data is done: pools lots of small studies together → safer, sounder results!!

Question 13

Benefits to mum: a metaanaylysis

Answer 13

There’s a variety of ways you can look at this!

Shows theres a lower chance of getting cancer if you’ve ever breast feed, compared with women who have ever breast feed.

(if it crosses 1 its an insignificant study as there’s no study for or against!)

Question 14

What are the benefits of Breast feeding to baby?

Answer 14

• Don’t get over-fed​​
  
  • at 12 months are leaner then controls
  • BF for 9 months are 400g less then formula fed babies
• Therefore BF may have a slight protection against childhood obesity
  
  • also less chance of diabetes
• Reduces poor outcomes (especially due to infectious diseases)
  
  • most noticeable where infant mortility or morbidity is high; 3^rd world countries
• Prevents exposure to dirty water in formula
  
  • stops exposure to diarrhea inducing pathogens (rotovirus)
  • Protective Factors: antibodies from mum

Question 15

Answer 15

The risk of developing GI tract infections in breast fed babies is reduced in comparison to never breast fed babies

Question 16

What does this study show about Otitis media and breast feeding?

Answer 16

There’s is a greatly reduced risk of breast fed babies developing otitis media/acute ear infections in comparison to never breast fed babies.

• Particularly have protection when feeding exclusively for more then 4-6months

Question 17

How does breast feeding affect babies atopy (allergies)

Answer 17

• Exclusive breastfeeding is protective against developy atopy
  
  • 60% of infants who develop atopic eczema do so in first 12 months of life
  • Infant intestinal mucosa is permeable to proteins in the first 6-9 months
  • The protective IgA system that later soaks up allergens is also poorly functional at this point: babies IS bad at this point, not fully developed to 3-5 yrs
• Exclusive breastfeeding is protective against developy asthma
  
  • reduces risk to 0.7 of risk of non-BF infant

In those with family members with issue, risk is Halved

Question 18

What does this MA tell us about Sudden Infant Death Syndrome?

Answer 18

• If you just look at the data by Brooke or Fleming: you would say BF is not protective*
• But by looking at other studies (mitchell, wennegren) there is a protective evidence.*

Overall: is calculated by weighing up the quality (size, number of participants) of the studies. Shows a decreased risk of SIDS in BF babies.

To get a larger weighting in the overall Result:

• Better Methodology
• Larger study

Question 19

Breast-feed babies and cognitive ability?

Answer 19

SUggested that substances like Docosahexaenoic Acid (DHA) in breast milk enhances cognitive ability

Confounders: maternal intelligence (smarter mums know to BF in the 1^st place)

Question 20

What is the major Downside of Breast feeding?

Answer 20

Disease/drug Transmission from mum → baby

• HIV: accounts for 1/2 all infanct HIV infections worldwide
• Mastitis
• Hep B
• Alcohol
• caffiene
• Nicotine

You need to weigh up the pros/cons of breast feeding to formula feeding! Easier in NZ as formula feeding is a viable option

Question 21

Mastitis risk and breast feeding?

Answer 21

Mastitis: infection of a lactiferous lobe; often a bacterial infection

Symptoms: a red triangle on the breast

This is not an indication to stop breastfeeding, we want to avoid stasis in the ducts.

Treatment: antibiotics

Question 22

Hepititis B risk and Breast feeding?

Answer 22

Probably no risk of infection, but if mum has a hep B infection (where highest risk is during birth), then babies are given HblgG to protect them, so babies in study have already been protected.

Question 23

Alcohol Transmission and Breast feeding?

Answer 23

• Levels of alcohol in milka are similar to maternal plasma
• Babies don’t suckle well post alcohol-consumption
  
  • may lead to feeding problems
• Vodka (meant to be oudourless) changes the smell of milk

Question 24

Caffeine tramission and breast feeding?

Answer 24

• Easily enters milk
• Babies can’t process as well as adults
  
  • Clearence is upto 80hrs (only 3.5hr in adults)
  • Builds up over a week, so 1 coffee wont hurt them
• Excess → sleeplessness and irritability

Question 25

Nicotine and Breast feeding?

Answer 25

* Nicotine can be **found in babies urine** (in both breast feed and bottle fed infants!!) * **Smoking always discouraged!**

Question 26

What's the Baby Friendly initiative?

Answer 26

* Launched by UNICEF * Aims to promote exclusive breastfeeding (except when medically indicated), guidance and enncouragment * All Auckland hospital units involved * We have exclusive 6 weeks rates 50-60% for 6 weeks, we can do better