Pregnancy Flashcards
What effect does oestrogen have on cardiac output?
Increases cardiac output by increasing pre-load and stroke volume
What effect does progesterone have on blood pressure?
BP is reduced as systemic vascular resistance drops by 20%
What major vein does the growing foetus put pressure on in later stages?
Inferior vena cava
What effect does increased pressure on the inferior vena cava have on BP?
Reduced BP due to reduced blood flow back in to the atrium
What happens to total blood volume in pregnancy? And why?
Increase total volume by 30-50% to meet the needs of the foetus and provide volume for uteroplatal perfusion
What happens to RBC volume during pregnancy?
Increases by 20-30%
Why may a pregnant woman experience anemia?
Increase in plasma volume disproportionate to increase in RBC, therefore relative anaemia
What does erythroprotein do?
Stimulates the production of RBC in bone marrow
What effect does progesterone have on respiration?
Increases minute volume
(Air breathed over 1minute)
What does an ABG specimen show in a pregnant woman?
Respiratory alkalosis with compensatory metabolic acidosis
What is hydronephrosis?
Swelling of kidneys due to a build up of urine
What effect does progesterone have on the kidneys?
It causes vasodilation so increases blood flow by 50%
How may the growing foetus impact the mother’s urinary system?
Compression of ureters obstructing the flow of urine to the bladder, increasing risk of acute kidney injury
After which week of pregnancy may gestational hypertension occur?
20
Why may gestational diabetes occur?
Cortisol-mediated insulin resistance so the foetus is not deprived of glucose
What physiological change happens to the pituitary gland and why?
Increase in size by 1/3rd due to hyperplasia of lactotrophs (new cells grow) in response to high oestrogen
Where is prolactin produced?
Lactotrophs in the pituitary gland
What does prolactin do?
Stimulate mammary gland development and stimulate lactation
The foetal skeleton formation requires calcium, what effect does this have on the mother?
Increase of parathyroid hormone causing increased uptake of dietary Ca, increase Ca reabsorption in the kidneys, increased osteoclast activity
What effect does pregnancy have on nervous grey matter?
Shrinks in size for up to 3 years post partum
What effect do oestrogen and relaxin have on the MSK system?
Remodelling of soft tissues and ligaments to allow for foetal growth
What hormone causes skin pigmentation changes?
Melanin
How are babies made?
Shagging
Why might a pregnant woman experience respiratory alkalosis?
Progesterone increases tidal volume, more CO2 (acidic gas) is blown off per minute, so circulating blood becomes relatively more alkali as a result of less acid
How does the body compensate for being in respiratory alkalosis?
Metabolic acidic compromise- decrease in serum bicarbonate mediated by kidneys
How much does BP drop during pregnancy?
10-15 mmHg
A 30week pregnant patient complains of dizziness when lying down, why and what advice would you give?
Increase pressure on the IVC when lying down reduces blood flow to the heart
Advice- lie on her side
Where is progesterone produced during weeks 0-10 of pregnancy?
Corpus luteum of the Ovaries
Where is progesterone produced after week 10 of pregnancy?
Placenta
What events confirm labour?
Uterine contractions
Progressive cervical dilation
Descent of presenting part of the baby
Which is the longest stage of labour?
Cervical dilation
Which hormone intensifies contractions in a positive-feedback mechanism?
Oxytocin
What are the functions of the placenta?
Facilitating blood flow
Gas exchange
Waste elimination
Barrier to infection
When is the placenta formed?
Once the blastocyst makes contact with the uterine wall
What is a common cause of post-partum haemorrhage?
Placental fragments remaining in the uterus
Which hormone increases cardiac output?
Oestrogen
-increases stroke volume
How may Pre-eclampsia be defined?
A new onset of hypertension (high BP) in pregnancy
