Antenatal Care and Screening Flashcards
1
Q
Why is physiological adaptation necessary in pregnancy?
A
To allow the body to cope with the added strain of pregnancy
2
Q
What are physiological changes in pregnancy responsible for?
A
So called minor ailments of pregnancy
Worsening of pre-existing illness
3
Q
What percentage of women are affected by morning sickness?
A
80-85%
4
Q
In what conditions is morning sickness worse?
A
Conditions where human chorionic gonadotrophin is higher e.g. twin pregnancy, molar pregnancy
5
Q
What can morning sickness progress to?
A
Hyperemesis gravidarum (this risk is also increased when HCG is increased)
6
Q
By what week of pregnancy does morning sickness usually improve?
A
16
7
Q
How much does cardiac output increase by during pregnancy? Why is this?
A
30-50%
Due to combination of increase in SV and HR
8
Q
What can the increase in heart rate in pregnancy be associated with?
A
Feeling of palpitations
9
Q
At term, what must the blood flow to the uterus exceed?
A
1L/min
10
Q
When does blood pressure drop in pregnancy?
A
During second trimester
11
Q
Why does blood pressure drop during the second trimester?
A
Expansion of uteroplacental circulation
Fall in systemic vascular resistance
Reduction in blood viscosity
Reduction in sensitivity to angiotensin
12
Q
When in pregnancy does BP usually return to normal?
A
In third trimester
13
Q
Why does urine output increase in pregnancy, particularly in third trimester?
A
Bladder capacity is reduced in third trimester due to pressure in the pelvis from the expanding uterus
14
Q
What is the increase in renal plasma flow and glomerular filtration rate in pregnancy?
A
Renal plasma flow increases by 25-59%
GFR increases by 50%
15
Q
What is the change in serum urea and creatinine in pregnancy?
A
Both decrease
Due to increased GFR and dilutional effect of increased plasma volume
16
Q
Why is there an easier path for ascending infection and increased pyelonephritis in pregnancy?
A
There is increased urinary stasis
17
Q
When is hydronephrosis phsyiological in pregnancy?
A
In third trimester
18
Q
Why is there a low threshold for MSSU and antibiotics for UTI in pregnancy?
A
UTI increases incidence of pre-term labour
19
Q
Why is the incidence of anaemia increased in pregnancy?
A
Increased iron requirement from foeto-placental unit
20
Q
When should iron supplements be given in pregnancy?
A
When Hb is < 110 at booking or < 100 on routine testing at 28 weeks
21
Q
What is the increase in plasma volume and RBC mass in pregnancy?
A
Plasma volume 50%
RBC mass 25%
22
Q
What is the increase in iron requirements in pregnancy?
A
1g
23
Q
What does WBC increase to in pregnancy?
A
9,000-12,000
24
Q
What does progesterone reduce?
A
CO2
25
What is the change in tidal volume, respiratory rate, plasma pH, O2 consumption and plasma PO2 in pregnancy?
```
TV - increases
RR - increases
plasma pH - increases
O2 consumption - increases
Plasma PO2 - unchanged
```
26
What is the change in oesophageal peristalsis and gastric emptying in pregnancy?
Oesophageal peristalsis is reduced
| Gastric emptying slows
27
What happens to the cardiac sphincter in pregnancy?
Relaxes
28
What happens to GI motility in pregnancy? Why?
GI motility is reduced due to increased progesterone and decreased motilin
29
Ideally, who should be given pre-pregnancy counselling?
All women
30
How many pregnancies in Scotland are unplanned
1/3rd
31
For what women is pregnancy counselling vital?
Women with any previous health or pregnancy problems
32
In what ways are the causes of maternal deaths changing?
BMI is increasing, weight related causes more common
Death from cardiac disease is relevant in an age group where it wasn't relevant before
Thrombosis would have been a cause of death in pregnancy but there are drugs which can prevent this and can be used in pregnancy so screening is important
33
What general health measures should be taken in pregnancy?
```
Improve diet
Optimise BMI
Reduce (stop) alcohol consumption
Smoking cessation
Folic acid
```
34
What might you need to consider when counselling a pregnant woman on smoking cessation?
Whether the partner/surrounding family smoke - will be more difficult for the woman to quit if she is surrounded by other smokers
35
What dose of folic acid should be given to pregnant women? Why?
400mcg, ideally for 3 months before becoming pregnant and then throughout pregnancy to reduce the risk of neural tube defects
36
How does obesity affect pregnancies?
Increased rates of poor outcomes including stillbirth and miscarriage
Affects function of uterus in pregnancy
Venous thromboembolic events more common
37
What does foetal alcohol syndrome cause?
Typical facial appearance
| Learning difficulties
38
What is the routine advice given to pregnant women regarding alcohol?
Avoid alcohol consumption completely during pregnancy
39
What ages of the fertile population carry worse pregnancy outcomes?
At either end - teenagers and older women
40
Why are teenagers more likely to have worse pregnancy outcomes?
May have less social support
Less antenatal care
Poor general health due to smoking and alcohol
41
Why are older women more likely to have worse pregnancy outcomes?
More prone to pre-existing medical conditions and complications of pregnancy
Increase in chromosomal disorders with maternal age
42
Why should blood pressure be monitored in pregnancy?
For signs of pre-eclampsia
43
When does pre-eclampsia usually occur?
In a woman's first pregnancy
44
What does grand multiparity predispose a woman to?
Postpartum haemorrhage
45
What substances can cause withdrawal syndrome in the baby when it is born and "cut off" from its supply?
Heroin
Methadone
Benzodiazepines
46
What should be done/considered in women with known medical problems during pregnancy?
Optimise maternal health
Remember psychiatric health
Stop/change any unsuitable drugs
Advise mother regarding complications associated with her medical problems
Occasionally may need to advise against pregnancy
Women with diabetes and epilepsy need to be counselled
47
What is phenylketonuria?
Error of protein metabolism which results in high levels of the amino acid phenylalanine
48
What does untreated phenylketonuria cause?
Mental development impairment
49
What needs to be done if a woman with PKU is pregnant?
She needs to re-start her low phenylalanine diet to prevent high levels reaching the developing foetal brain
50
How is the demand for thyroxine in women with hypothyroidism affected by pregnancy?
Demand is increased so dose may need to be increased
51
Why are normal thyroxine levels needed in pregnancy?
Needed for foetal brain development
52
Ideally, when should glucose control in women with diabetes be optimised?
Prior to conception
53
What changes need to be made in medication of women with diabetes who are taking oral medications?
Medications need to be switched to insulin
54
What pregnancy complications are diabetic mothers more at risk of?
Pre-eclampsia
Stillbirth
Macrosomic infant
55
Where should diabetic pregnant women be cared for in pregnancy?
Joint diabetic-obstetric antenatal clinic
56
What are renal patients more likely to develop in pregnancy than normal women?
Pre-eclampsia
57
Why might pre-eclampsia be difficult to diagnose in women with pre-existing renal problems?
They may already have proteinuria and hypertension
58
What effect does renal transplantation have on fertility?
Restores fertility as well as renal function
59
What is the main concern for women with epilepsy in pregnancy?
The effect of their anti-epileptic medication on the developing foetus - some medications e.g. sodium valproate are extremely teratogenic
60
What are the rules regarding sodium valproate treatment of epilepsy in women of child-bearing age?
Sodium valproate should not be given to women of child-bearing age where there is an alternative
61
Why is it important to review a patient's medication history when pregnant/trying to conceive?
In order to identify any drugs contraindicated in pregnancy and see if drugs can be safely discontinued or modified
62
How does a previous Caesarean section delivery affect a woman's safest mode of delivery for subsequent pregnancies?
If a caesarean was given for a non-recurring cause such as breech presentation the woman will normally be fine to undergo normal labour, if a woman has had 2 previous caesarians it is customary to deliver by elective caesarean again
63
What might a previous pregnancy indicate?
How a woman is likely to progress in subsequent pregnancies
64
Why is antenatal care important?
High quality antenatal care reduces foetal and maternal mortality
65
What do antenatal examinations aim to identify?
Problems with the mother and foetus, and any social problems
66
What problems are important to detect in the mother?
Pre-existing or developing illness
| Problems of pregnancy e.g. anaemia
67
What does examination of the foetus allow?
Detection of some foetal abnormalities and foetuses that are small for their gestational age
68
What is included in routine enquiry after 20 weeks of pregnancy?
Asking the mother about foetal movements
69
What is done at every antenatal appointment?
Blood pressure and urinalysis
70
What does abdominal palpation of a pregnant woman allow?
```
Asses symphyseal fundal height
Estimate size of baby
Estimate liquor volume
Estimate foetal lie
Determine foetal presentation
```
Can also listen to foetal heart during this examination
71
What is important to tell patients when talking about screening for foetal abnormality?
Women are offered screening but it is not compulsory
| Patients should be aware of potential repercussions
72
What does screening allow?
Conditions to be detected in a symptomless population
73
What infections can be screened for in pregnancy?
Hepatitis B
Syphilis
HIV
UTI
74
Why is it important to identify hepatitis B in pregnant women?
If women are infected you can provide both active and passive immunisation to the neonate at birth
Can also alert healthcare workers of the woman's infectious status
75
What does congenital syphilis cause?
Intrauterine growth restriction, hepato-splenomegaly, anaemia, thrombocytopaenia and skin rashes
76
How does HIV infection affect pregnancy?
Prior knowledge of HIV status allows the use of antiretrovirals to reduce viral load
Delivery is usually by Caesarean section and breastfeeding is avoided to reduce vertical spread
77
What can happen when a rhesus-negative woman is carrying a rhesus-positive baby? (Due to the father being rhesus-positive)
The woman develops anti-D antibodies if the foetal red blood cells enter the maternal circulation, these cause the baby to become anaemic and can cause foetal death
78
What is offered to all rhesus-negative women? When?
Anti-D IgG, both prophylactically and after potentially sensitising events
79
What is the aim of the first visit ultrasound scan?
Ensure pregnancy is viable
Identify multiple pregnancy
Identify abnormalities incompatible with life
Offer and carry out Down syndrome screening
80
What is the purpose of the detailed anomaly scan?
Systematic structural review of the baby to identify problems that need intrauterine or postnatal treatment, not possible to identify all problems
81
What is the overall risk of Down syndrome?
1 in 700
82
What is the biggest risk factor for having a baby with Down syndrome?
Increasing maternal age
83
What must women and their partners be aware of prior to any screening taking place for foetal abnormality?
Screening only provides a risk of their baby being affected, not a definite answer
84
When is first trimester screening carried out?
At 10-14 weeks gestation
85
What does first trimester screening involve?
Maternal risk factors
Serum beta human chorionic gonadotrophin
Pregnancy associated plasma protein A
Nuchal translucency measurement
86
What is the detection rate of trisomy 21 in first trimester screening?
90%
87
What causes nuchal translucency to increase?
Increases with gestational age
| Incidence of chromosomal abnormalities is related to size of nuchal translucency (rather than the appearance)
88
When is further testing for Down syndrome offered?
If risk is > 1 in 150
89
What are the options of further testing methods for Down syndrome?
Chorionic villus sampling
Amniocentesis
Non-invasive prenatal testing
90
When is CVS offered and what is the risk of miscarriage with this procedure?
Between 10-14 weeks
| 1-2% risk
91
When is amniocentesis offered and what is the risk of miscarriage with this procedure?
15 weeks onwards
| Around 1% risk
92
How does non-invasive prenatal testing work?
Maternal blood taken
| Can detect foetal cell free DNA and use this to look for chromosomal trisomies
93
What screening tests are available for neural tube defects?
Ultrasound
| Biochemical screening - maternal serum tested for alpha fetoprotein
94
What is the purpose of the second trimester ultrasound?
Detecting foetal abnormality
| Good screening test for major structural abnormalities but poor test for chromosomal abnormalities
95
What percentage of foetuses with T21 will have a normal detailed second trimester US?
50%
96
What percentage of foetuses with T18 will have a normal detailed second trimester US?
17%
97
What percentage of foetuses with T13 will have a normal detailed second trimester US?
9%
