Pregnancy Flashcards
Below what body fat percentage does ovulation cease?
22%.
Below what body mass is amenorrhoea a risk?
<47 kg.
List 3 features of the changes of maternal physiology.
1) Anticipatory —> precedes foetal growth and demand
2) In excess —> in excess of foetal demand
3) Dynamic —> changes vary through the trimesters
List 3 symptoms that occur due to changes to the renal system during pregnancy.
1) Generalised oedema
2) Increased thirst
3) Decreased urine output
List 3 physiological features that occur due to changes to the renal symptoms.
1) Increased creatinine output
2) Glucosuria
3) Aminoaciduria
List 2 conditions that are at risk due to changes to the renal system during pregnancy.
1) Hydronephrosis (esp. RHS)
2) Pyelonephritis (esp. RHS)
How does total plasma volume change during pregnancy?
Increases, 1-2 L (30-50%).
How does plasma osmolality change during pregnancy?
Decreases, 280 mosmol/kg (NP) —> 270 mosmol/kg (T).
List 2 natriuretic factors during pregnancy.
1) Progesterone
2) Atrial natriuretic peptide
List 4 antinatriuretic factors during pregnancy.
1) Aldosterone
2) Renin
3) Angiotensin
4) Deocycorticosterone
Why is eGFR not a valid measure of kidney function during pregnancy?
1) Creatinine output increases
2) Plasma creatinine decreases
How does kidney size change during pregnancy?
Increases, 20% by term.
List 4 signs that occur due to changes to the cardiovascular system during pregnancy.
1) Decreased blood pressure (early/mid pregnancy)
2) Increased blood pressure (late pregnancy)
3) Altered heart sounds
4) Altered ECG trace
List 2 physiological features that occur due to changes to the cardiovascular system during pregnancy.
1) Increased cardiac output
2) Increased pulmonary flow
List 2 conditions that are at risk due to changes to the cardiovascular system during pregnancy.
1) Dilutional anaemia
2) Thromboembolism
How does cardiac output change during pregnancy?
Increases, 30-50%.
How long postpartum does the risk of thromboembolism persist?
6-8 months.
Which 3 clotting factors increase during pregnancy?
1) VII
2) VIII
3) X
List 7 cardiac anatomical changes that occur during pregnancy.
1) Diaphragm elevates 4 cm
2) Heart displaces superiorly and laterally
3) Apex displaces laterally
4) Heart is more horizontal
5) Increased left atrium size
6) Increased left ventricle size
7) Increased ventricular muscle mass
List 4 ECG abnormalities found during pregnancy.
1) Lead III —> inverted T wave
2) Lead III —> prominent Q wave
3) Lead aVF —> prominent Q wave
4) 15 degree left axis deviation
List 3 lung function test changes that occur due to changes to the respiratory system during pregnancy.
1) Increased tidal volume
2) Increased vital capacity
3) Decreased total lung volume
List 4 respiratory anatomical changes that occur during pregnancy.
1) Diaphragm elevates 4 cm
2) Increased subcostal angle (70 degrees (NP) —> 105 degrees (T))
3) Increased thoracic circumference
4) Decreased chest compliance
How does tidal volume change during pregnancy?
Increases, 450 ml (NP) —> 650 ml (T), 200ml (40%).
Explain why pregnant women experience subjective dyspnoea.
Due to the increased tidal volume, pregnant women take deeper breaths, so they feel as though they are out of breath.
How does total lung volume change during pregnancy?
Decreases, 4200 ml (NP) —> 4000 ml (T), 200 ml.
List 5 lung function tests that are unchanged during pregnancy.
1) Respiratory rate
2) FEV1
3) FVC
4) FEV1/FVC
5) Peak flow
How does PCO2 change during pregnancy?
Decreases, 4.7 kPa (NP) —> 4.0 kPa (T).
Describe how compensated respiratory alkalosis occurs during pregnancy. (6)
1) Progesterone mediated increased CO2 sensitivity of respiratory centre chemoreceptors
2) Increased tidal volume
3) Increased CO2 exhaled
4) Decreased PCO2
5) Respiratory alkalosis
6) Excess HCO3- renally excreted
Describe how respiratory alkalosis enables placental CO2 exchange during pregnancy. (5)
1) Foetal PCO2 —> 5.0 kPa
2) Maternal PCO2 —> 4.0 kPa
3) Foetal PCO2 > maternal PCO2
4) Foetal:maternal CO2 diffusion gradient
5) CO2 diffusion across placenta
How does oxygen consumption change during pregnancy?
Increases, 250 ml/min (NP) —> 300 ml/min (P) (15-20%).
Describe how maternal and foetal erythrocytes enable placental O2 exchange. (4,3)
Maternal erythrocytes
1) Increased 2,3-diphosphoglycerate (DPG)
2) Increased DPG O2 binding in M erythrocytes
3) Decreased M erythrocyte O2 affinity
4) Favours M erythrocyte O2 unloading
Foetal erythrocytes
1) F haemoglobin contains 2 alpha and 2 gamma chains
2) Increased F erythrocyte O2 affinity
3) Favours F erythrocyte O2 loading
Describe the double Bohr effect during placental O2 exchange. (7)
1) Placental CO2 exchange
2) Relative high M CO2
3) Acidic M blood
4) Favours M O2 unloading
5) Relative low F CO2
6) Alkaline F blood
7) Favours F O2 loading
List 4 conditions that are at risk due to changes to the gastrointestinal and hepatic system during pregnancy.
1) Gastro-oesophageal reflux
2) Aspiration pneumonitis
3) Cholelithiasis
4) Obstetric Cholestasis
List 4 symptoms that occur due to changes to the gastrointestinal and hepatic system during pregnancy.
1) Constipation
2) Vomiting
3) Excess salivation
4) Altered appetite (inc. pica)
Define pica.
Ingestion of non-nutritive substances.
List 6 reasons why drug metabolism alters during pregnancy.
1) Decreased gastric pH
2) Decreased gastric emptying
3) Increased gastric transit time
4) Altered cytochrome P450 enzyme activity
5) Increased ECF volume
6) Increased GFR
How does gut transmit time change during pregnancy?
Increases, 52 hours (NP) —> 58 hours (P).
List 3 conditions that are at risk due to changes to the metabolic system during pregnancy.
1) Hyperlipidaemia
2) Gestational diabetes mellitus
3) Diabetes ketoacidosis
When does hyperlipidaemia occur during pregnancy?
During early pregnancy, to build fat reserves.
What is the incidence of gestational diabetes mellitus?
1-2%.
When is diabetic ketoacidosis likely to occur during pregnancy?
Overnight.
List 2 anatomical changes that occur due to changes to the reproductive system during pregnancy.
1) Increased uterine mass
2) Increased breast volume
How does uterine mass change during pregnancy?
Increases, 46 g (PT) —> 1012 g (T).
List 2 ways how uterine mass increases during pregnancy.
1) Smooth muscle hyperplasia
2) Smooth muscle hypertrophy
Describe how uroplacental blood flow is established. (4)
1) placental extravillous trophoblasts invade uterine decidual spinal arteries
2) Spinal arteries are remodelled
3) Endovascular invasion of placenta
4) Placenta acquires maternal blood supply
List 5 conditions that are at risk due to failed endovascular invasion.
1) Pre-eclampsia
2) Premature birth
3) Recurrent miscarriage
4) Placental abruption
5) Foetal growth restriction
What proportion of maternal deaths are caused by medical and mental health problems versus direct pregnancy complications? (2)
1) medical and mental health —> 2/3
2) direct pregnancy complications —> 1/3
List 3 considerations during a preconception assessment for a woman with a pre-existing medical condition.
1) effect of pregnancy on medical condition
2) effect of medical condition on pregnancy
3) effect of maternal medication on pregnancy
List 4 treatment aims during a preconception assessment for a woman with a pre-existing medical condition.
1) optimise disease control —> stable
2) rationalise drug therapy —> minimise effects on baby
3) advise on risks to mother and baby
4) effective contraception until ready to conceive
List 3 healthcare professionals involved in a joint obstetric-medical clinic.
1) obstetrician with medical expertise
2) physician with pregnancy expertise
3) nurse/midwife specialist
List 3 advantages of a joint obstetric-medical clinics.
1) improved communication
2) loss hospital visits
3) facilitates audits and research
List 4 considerations for delivery and postpartum care during a joint obstetric-medical clinics.
1) safest mode of delivery
2) neonatal support
3) anaesthetic expertise
4) available HDU/ITU facilities
List 2 pregnancy risks due to iron deficiency anaemia.
1) low birthweight
2) preterm delivery
List 2 pregnancy risks due to asthma.
1) foetal growth restriction
2) premature delivery
When is an asthmatic exacerbation during pregnancy most likely?
3rd trimester.
What is the leading cause maternal death during pregnancy?
Cardiac disease.
List 4 high risk cardiac lesions during pregnancy.
1) aortic stenosis
2) coarctation of aorta
3) prosthetic valves
4) cyanosis
List 4 low risk cardiac lesions during pregnancy.
1) mitral regurgitation
2) aortic regurgitation
3) atrial septal defect
4) ventricular septal defect
How do you manage cardiac disease during pregnancy? (5)
1) screen for heart failure (echo, ECG)
2) anticoagulation (mechanical heart valves)
3) rationalising drug therapy
4) monitor foetal growth and wellbeing (scans)
5) plan delivery (timing and mode)
List 4 pregnancy risks due to hyperthyroidism.
1) maternal thyroid crisis with cardiac failure
2) maternal propylthiouracil induced liver failure
3) foetal thyrotoxicosis
3) foetal carbimazole induced abnormalities
List 2 pregnancy risks due to hypothyroidism.
1) foetal impaired neurodevelopmental
2) foetal death
Define gestational diabetes mellitus.
Carbohydrate intolerance first recognised in pregnancy.
What is the period of risk for developing type 2 diabetes mellitus following gestational diabetes mellitus?
Within 10-15 years of pregnancy.
How do you manage diabetes mellitus during pregnancy? (5)
1) HbA1c < 48 mM
2) folic acid 5 mg
3) stop ACEi and statins
4) retinal screening
5) renal screening
List 4 maternal risks associated with diabetes during pregnancy.
1) diabetic ketoacidosis
2) hypoglycaemia
3) retinopathy
4) pre-eclampsia
List 6 foetal risks associated with diabetes during pregnancy.
1) miscarriage
2) prematurity
3) still birth
4) macrosomia
4) foetal abnormalities
5) hypoglycaemia
6) respiratory distress
List 3 drugs used for diabetes mellitus during pregnancy.
1) insulin (basal bolus regime)
2) metformin
3) glibenclamide
List 4 maternal risks associated with chronic kidney disease during pregnancy.
1) severe hypertension
2) renal function deterioration
3) pre-eclampsia
4) Caesarean section
List 4 foetal risks associated with diabetes during pregnancy.
1) prematurity
2) stillbirth
3) growth restriction
4) foetal abnormalities (iatrogenic)
List 4 factors that determine the outcome of a pregnancy for a mother with chronic kidney disease.
1) degree of renal dysfunction
2) blood pressure
3) creatinine level
4) proteinuria
How does seizure frequency change during pregnancy?
Increases, 25-33%.
Why is SUDEP more common during pregnancy?
Increased likelihood of non-compliance to anticonvulsants due to fear of harming baby.
List 2 foetal risks associated with epilepsy during pregnancy.
1) foetal abnormality (iatrogenic)
2) hypoxia (associated with maternal seizures
How do you manage epilepsy during pregnancy? (5)
1) high dose folic acid
2) screen for foetal abnormalities
3) control seizures
4) plan for delivery (paint relief)
5) avoid prolonged labour
List 5 risks of in utero exposure to valproate. (7)
1) spina bifida
2) atrial septal defect
3) cleft palate
4) hypospadias
5) polydactyly
6) reduced IQ
7) autistic spectrum disorder
List 3 risk factors for thromboembolism in pregnancy.
1) maternal age
2) BMI
3) operative delivery
What is the VTE of choice during pregnancy?
Low molecular weight heparin.
