Physiology of Pregnancy

Question 1

What are the changes that can occur to the mammary glands during pregnancy

Answer 1

• Puberty
  ○ Estrogen promotes growing of ducts and increases fat deposition (Breast development)
• Pregnancy
  ○ Estrogen, growth hormone and cortisol stimulate further gland development
• Late Pregnancy
  ○ Progesterone will promote the development of secretatory epithelium
  ○ Consists of lobule that will secrete the milk which then moves into the milk duct

Question 2

What is the process by which lactation occurs

Answer 2

• During Pregnancy
  ○ Estrogen and prolactin-inhiting hormone (PIH) will prevent milk productionj
• After Birth
  ○ High prolactin and low estrogen lead to lactation
  ○ Breast milk contains nutrients and immunity
• Suckling
  ○ Will stimulate the production of prolactin
  ○ Will also promote the release of oxytocin, this will promote milk ejection
  ○ Together this inhibits GnRH and ovarian cycle
  § Hence cannot get pregnant

Question 3

What are the main stages of growth

Answer 3

- Early embyro 
	○ Week 1-2
	○ Not susceptible to teratogens
	○ Will usually implant into the uterus by day 5
- Embyro
	○ Week 3-8
	○ Most susceptible to teratogens
	○ All organs have developed by this stage
- Foetus
	○ Weeks 9-38
	○ Organs will grow and proliferate
	○ Minor morpholigical abnormalities can be obtained in this stage

Question 4

What are the physiologic changes that can occurs during pregnancy

Answer 4

Cardiac changes (HR, CO and SV), breast enlargement, increased blood volume, Increased tidal volume and RR, and pigmentation changes due to melanocyte activation (Nipples),