Maternal Problems in Pregnancy Flashcards
What are the constituents of antenatal screening?
- History and examination
- Blood test
- Urinalysis
What is being looked for in the history and examination stage of antenatal screening?
Risk factors, e.g. for gestational diabetes
What is being looked for in a blood test in antenatal screening?
- Rhesus incompatability
- Haemoglobin
- Infection
What rhesus incompatability is significant?
-ve mother with +ve fetus
Why is it important to intervene early when there is a rhesus incompatability?
To prevent this from preventing future pregnancies
Why should haemoglobin be tested in antenatal screening?
Because there is a risk of anaemia development in pregnancy due to the high iron demans of the fetus
Why is it important to check for infections in antenatal screening?
Because they can be tetragenic
Give two examples of infections it is important to check for in antenatal screening
- Syphilis
- HIV
Why is it important to check for syphilis in antenatal screening?
Can cause congenital defects
Why is it important to check for HIV in antenatal screening?
Concerns about vertical transmission
What should be checked for in urinalysis in antenatal screening?
Proteinuria
What is the importance of proteinuria in antenatal screening?
Sign of pre-eclampsia, indicating systemic organ involvement as a result of maternal syndrome
What systems undergo physiological changes in pregnancy?
- Cardiovascular system
- Respiratory system
- Metabolic changes
- Gastrointestinal system
- Immune system
- Haemotology
What happens to the cardiovascular system in pregnancy?
Many haemodynamic changes occur
When do the haemodynamic changes occur in pregnancy?
Very early
Why do the haemodynamic changes in pregnancy occur very early?
Strong anticipatory changes, reflective of the need to supply big utero-placental circulation, required for later need
By how much does the blood volume increase in pregnancy?
50%
Why does the blood volume increase by 50% in pregnancy?
- Because there is a new circulation to support
- Have to increase blood flow to the kidneys
- Pre-empt blood loss at delivery
Why is there an increased blood flow to the kidneys in pregnancy?
Because mum’s kidneys have to act for the fetus
How much blood loss is expected in a normal vaginal delivery?
0.5L
How much blood loss is expected in a caeserian?
1L
Is systolic BP increased in pregnancy?
No
What happens to blood pressure in T1 and T2?
Progesterone has effects on systemic vascular resistance, and so decreases BP
What is the result of the decreased blood pressure in T1 and T2?
Increased risk of vaso-vagal episodes
What happens in a vaso-vagal episode?
Nausea and feeling faint
What is the problem with the hypotension in T1 and T2 of pregnancy?
Can mask exisiting hypertension, which is a risk factor for pre-eclampsia
What can happen to blood pressure in T3?
May be aortocaval compression by gravid uterus, leading to hypotension
What causes a gravid uterus?
Significant hypertrophy of the myometrium and enlarged fetus
What should be considered due to aortocaval compression by a gravid uterus?
Shouldn’t leave pregnant woman supine for a long time
Why shouldn’t a pregnant woman be left supine for a long time?
Reduces perfusion to the placenta, and so decreases oxygen exchange
What is the important of the endothelium in pregnancy?
- Controls vascular permeability
- Contributes to the control of vascular tone
How does endothelium contribute to the control of vascular tone in pregnancy?
By signalling to smooth muscle
Is there normal vasodilation in pregnancy?
Yes
What is the difference in plasma volume between normal pregnancy and pre-eclampsia?
Plasma expanded in normal pregnancy, contracted in pre-eclampsia
What is the difference in vasodilation between normal pregnancy and pre-eclampsia?
Vasodilation in normal pregnancy, vasoconstriction in pre-eclampsia
Why does blood pressure increase in pre-eclampsia?
There is a big strain on the placenta, so not able to support fetus, so increase in BP to try and compensate
What is pre-eclampsia characterised by?
- Defect in placentation
- Poor uteroplacental circulation
- Widespread endothelial dysfunction throughout maternal CNS
What is pre-eclampsia a precursor to?
Eclampsia
What is eclampsia?
Significant generalised seizures
What is the problem with eclampsia?
It is bad for the mother and baby, and so is an emergency situation
What happens to cardiac output in pregnancy?
+40%
When does cardiac output change in pregnancy?
From T1
What happens to stroke volume in pregnancy?
+35%
When does stroke volume change in pregnancy?
From T1
What happens to heart rate in pregnancy?
+15%
When does heart rate change in pregnancy?
From T1
What happens to systemic vascular resistance in pregnancy?
- 25-30%
When does systemic vascualr resistance change in pregnancy?
From T1
What happens to blood pressure in pregnancy?
Decreases in T1 and T2, then returns to normal in T3