Adaptations of Digestive System Flashcards
What percentage of women have an increased appetite and thirst during pregnancy?
- 50%
Why do women have an increase in appetite in early pregnancy?
- Due to pregnancy induced CENTRAL LEPTIN RESISTANCE
- Causes increased food intake and fat deposit
Why do women have an increased thirst during pregnancy?
- HCG affects the hypothalamus by DECREASING osmotic threshold for thirst.
What does pregnancy induced central leptin resistance increase? (x2)
- Food intake
- Fat deposit
What does leptin usually do?
- Suppress appetite to maintain a healthy BMI.
In late pregnancy why does gastric displacement occur?
- Due to the enlarging uterus which causes a reduction in capacity for food intake.
What 2 hormones affect appetite? How?
- PROGESTERONE (stimulates appetite)
- OESTROGEN (decreases appetite)
Cravings and Aversions
- Some food choices are deliberate (recommended/avoided in pregnancy via midwife’s advice) e.g. listeria avoided
- Taste buds are DULLED during pregnancy, women may crave strong flavours e.g. pickles
- Aversions to alcohol/tea/coffee/smoking
- PICA (extreme craving of non-nutritious substance) e.g. coal/disinfectant
- Changes to smell/taste linked to HCG secretion in early pregnancy
What is pica? (cravings and aversions)
- Extreme craving of a non-nutritious substance e.g. coal/ soap/ disinfectant
Gums (+saliva)
- Increased vascularity/oedema/spongy gums
(due to oestrogens effects on blood) - Gums bleed more during pregnancy
- Saliva becomes more acidic (rare cases saliva can increase pytalism)
Heartburn
- Caused by regurgitation of stomach contents
- PROGESTERONE –> relaxes cardiac sphincter at entrance of stomach
(continues throughout pregnancy due to mechanical displacement of the stomach due to enlarging uterus)
MIDWIVES ROLE
–> refer to GP for gaviscon/omeprozole
What is heartburn caused by?
- Regurgitation of stomach contents
What medications are prescribed by the GP to individuals with severe heartburn?
- Gaviscon
- Omeprazole
What does progesterone do in relation to heartburn?
- Relaxes cardiac sphincter at entrance of the stomach
Why does regurgitation of the stomach contents continue to occur throughout pregnancy, sometimes causing heartburn?
- Due to mechanical displacement of the stomach (Due to enlarging uterus)
What is the midwives role in relation to heartburn?
- Refer to GP for gaviscon or omeprazole.
How does omeprazole work to reduce heartburn?
- Prevents proton pumps working properly (proton. pumps line the stomach and make acid for digestion)
- This reduces the amount of acid the stomach makes
What is often the first symptom of pregnancy and how long can this symptom occur for?
- Nausea and vomiting
- 16th weeks gestation
Why has progesterone been linked to vomiting?
- Delayed GASTRIC EMPTYING
- (because it relaxes the smooth muscle)
Why is nausea and vomiting seen as a evolutionary mechanism?
- Protects the fetus from potential teratogenic substances
What is a teratogenic substance?
- Substances that can cause congenital disorders in developing embryos/fetus’
- E.g. drugs, infections, toxins
What has been linked to vomiting and nausea but has not been clearly established?
- Peak HCG levels in early pregnancy
What is severe sickness called?
- Hyperemesis
What is the midwives role for individuals with severe nausea and vomiting?
- Dietary advice (eating little and often) (dry foods)
- Referrals if required (e.g. anti-sickness medication/ IV hydration drip i.e isotonic saline)
What are the 2 increased maternal demands that cause maternal metabolism changes in pregnancy?
- Accumulation of energy stores for labour and lactation e.g. glucose—>glycogen
- Facilitation of fetal growth and development
What fetal aspect causes a change in metabolic rate?
- Need to facilitate the accumulation of fetal energy stores for its transition to extrauterine life.
What happens to the metabolic rate during pregnancy?
- INCREASES
What is the role of the midwife in metabolic rate?
- Dietary advice
How does progesterone link to constipation during pregnancy?
- Relaxation of smooth muscle causes movement of chyme in the large intestine to slow down.
(allows for more time for reabsorption of WATER and NUTRIENTS)
Which 5 components are absorbed increasingly during pregnancy? + What is the benefit of this?
- IRON
- CALCIUM
- GLUCOSE
- WATER
- AMINO ACIDS
(supplies body and fetes with required nutrients)
What is the role of the midwife if an individual suffers with constipation during pregnancy?
- Referral to GP for lactulose
- Advise to drink lots of water
What happens in early pregnancy in relation to carbohydrate metabolism and insulin resistance?
- Increased response to insulin so blood glucose levels drop.
- Increased sensitivity to insulin which means there is an increased uptake of nutrients by cells.
(promotes maternal tissue growth)
How does oestrogen effect insulin secretion during early pregnancy?
- Stimulates growth of pancreatic beta cells causing insulin secretion to also increase.
What happens in late pregnancy in relation to carbohydrate metabolism and insulin resistance?
- Fetal unit growth and placental hormones (e.g. HPL) increase. (These are ANTAGONISTIC to insulin)
- This means maternal tissues become resistant to insulin, meaning insulin is less effective at stimulating glucose uptake
What component has an increased level during pregnancy which is transported to the foetus? (insulin res and carb met)
- Circulatory glucose
