Clinical- Week 3 Flashcards
1
Q
what is offered to all rheusus negative mothers at 28 weeks gestation?
A
anti-D
2
Q
at how many weeks is the booking scan performed?
A
8-12 weeks
3
Q
what is the ‘lie’ of a foetus?
A
relation of foetal spine to maternal spine
4
Q
if the foetal spine is parallel to the maternal spine, what is the lie?
A
longituindal lie
5
Q
if the foetal spine is perpendicular to the maternal spine, what is the lie?
A
transverse lie
6
Q
what down’s syndrome risk assessment is done in the first trimester?
A
combined US (for Nuchal thickness) and serum screening (HCG and PAPP-A)
7
Q
at how many weeks gestation is the combined US and serum screening for down’s syndrome risk assessment performed?
A
11 - 13+6 weeks
8
Q
what is nuchal thickness?
A
thickness behind fetal neck
9
Q
what down’s syndrome risk assessment is done in the second trimester?
A
blood sample for assay of HCG and AFP
10
Q
at how many weeks gestation is blood sample assay of HCG and AFP for down’s syndrome risk assessment performed?
A
15- 20 weeks
11
Q
what ratio of AFP and HCG indicate a high down’s syndrome risk?
A
low AFP and high HCG
12
Q
what specific diagnostic tests are done for down’s syndrome?
A
amniocentesis
chorionic villus sampling
13
Q
at what gestation can amniocentesis be performed?
A
after 15 weeks
14
Q
at what gestation can chorionic vilus sampling be performed?
A
after 12 weeks
15
Q
which has a higher miscarriage rate- amniocentesis or chorionic villus sampling?
A
chorionic villus sampling (0.2% compared to 0.1%)
16
Q
compare the functions of the inner and outer cell layers of a blastocyst?
A
inner- becomes embryo
outer- becomes placenta
17
Q
by what day does the blastocyst become completely buried in the endometrial lining?
A
day 12
18
Q
trophoblast cells (known as the chorion) differentiate into what multinucleated cells?
A
syncytiotrophoblasts
19
Q
what is the function of syncytiotrophoblasts?
A
invade decidua and break down capillaries to form cavities filled with maternal blood
20
Q
at what week is the placenta functional by?
A
5th week
21
Q
at what week is the foetal heart functional by?
A
5th wek
22
Q
before the placenta is in control of foetal nutrition, how does the fetus get nutrition?
A
trophoblastic nutrition
23
Q
what stimulates the decidual cells to concentrate glycogen, proteins and lipids in the trophoblastic nutritional phase?
A
progesterone (from corpus luteum)
24
Q
what blood vessel returns oxygen-saturated blood to the fetus from the placenta?
A
umbilical vein
25
what blood vessel returns oxygen-poor blood to the mother from the placenta?
uterine vein
26
what is the difference about fetal haemoglobin?
increased ability to carry oxygen
| higher concentration of Hb in fetal blood
27
what is the Bohr effect?
fetal Hb can carry more oxygen in low CO2 pressures than in high pressures
28
what are the 3 main functions of human chorionic somatomammotropin?
- growth-hormone like (protein tissue formation)
- decreases insulin sensitiviy in mother (more glucose for fetus)
- breast development
29
what is the main functions of human chorionic gonadotropin?
-prevents loss of corpus luteum
30
what are the 3 main functions of progesterone in a pregnant mother?
- development of decidual cells
- decreases uterus contractility
- preparation for lactation
31
what are the 3 main functions of oestrogens in a pregnant mother?
- enlargement of uterus
- breast development
- relaxation of ligaments
32
what are the 3 main oestrogens?
estradiol
estriol
estrone
33
what hormones cause hypertension in pregnancy?
placental CRH
| leading to increased maternal ACTH and then aldosterone
34
what hormones cause oedema in pregnancy?
placental CRH
| leading to increased maternal cortisol
35
what hormones cause hyperthyroidism in pregnancy?
placental HCG and HC thyrotropin
36
what cases hyperparathyroidism in pregnancy?
increased Ca demands of the placenta
37
what happens to the maternal cardiac output in pregnancy?
generally increases
| decreases in last 8 weeks
38
why does the maternal cardiac output decrease in the last 8 weeks?
in some body positions uterus can compress vena cava
39
what happens to the maternal heart rate in pregnancy?
increases up to 90/min
40
what happens to the maternal BP in pregnancy?
decreases during 2nd trimester
41
what happens to maternal plasma volume in pregnancy?
increases
42
what happens to maternal Hb concentration in pregnancy?
decreases (due to dilution- plasma volume is increased)
43
what happens to the maternal iron requirements in pregnancy?
increases
44
why does maternal lung function change in pregnancy?
due to progesterone and enlarging uterus
45
what does progesterone do to CO2 levels in pregnancy?
lowers them
46
how does progesterone lower CO2 levels in pregnancy?
increases respiratory rate and tidal volume
47
what happens to GFR and renal plasma flow in pregnancy?
increases
48
what is pre-eclampsia?
pregnancy induced hypertension with proteinuria
49
at what week can pre-eclampsia occur?
from week 20
50
where does oedema tend to occur in pre-eclampsia?
hands and face
51
what happens to the renal blood flow and glomerular filtration rate in pre-eclampsia?
decreases
52
what is the most significant risk factor for pre-eclampsia?
previous pre-eclampsia
53
what is the treatment of eclampsia?
vasodilators
| cesarean section
54
what is the average maternal weight gain in pregnancy?
24 pounds
55
how heavy is the average fetus?
7 pounds
56
how many extra calories should a pregnant lady take per day?
250-300extra kcal/day
57
what are the 2 metabolic phases of pregnancy?
1. up to week 20 (mothers anabolic phase, low metabolic demands of fetus)
2. 21-40 week (carabolic phase, high metabolic demands of fetus)
58
in what phase- anabolic or catabolic- of pregnancy does a maternal insulin resistance occur?
catabolic phase
59
what 3 hormones cause insulin resistance in pregnancy?
human chorionic sommatomammotropin
placental CRH
growth hormone
60
why is vitamin K often given before labour?
to prevent intracranial bleeding during labour
61
why does the uterus become more excitable towards the end of pregnancy?
change in oestrogen:progesterone ratio (oestrogen increases contractility, progesterone inhibits)
62
what are braxton-hicks contractions?
false labour contractions- similar but not labour, increase towards end of pregnancy
63
what does stretching the cervix by fetal head do to the contractility of the uterus?
increases it
| positive feedback
64
what does stretching the cervix by fetal head do to oxytocin release from the maternal pituitary gland?
increases it
| positive feedback
65
describe the 3 stages of labour?
1. cervical dilation (8-24 hours)
2. passage (up to 30 mins)
3. expulsion of placenta
66
what hormones drive cervical dilation?
oxytocin and oestrogen
67
why is it important that oestrogen and progesterone levels drop at birth?
because they inhibit milk production
68
how does oestrogen prepare for lactation?
causes growth of ductile system in mammary tissue
69
how does progesterone prepare for lactation?
causes development of lobule-alveolar system in mammary tissue
70
what liquid is produced by the breast before milk production occurs?
colostrum
71
describe colostrum in comparison to milk?
low volume, no fat
72
what hormone stimulate milk production?
prolactin (1-7 days after birth)
73
what hormone causes milk to be ejected?
oxytocin
74
what stimulus cause milk to be ejected?
baby suckling on mechanoreceptors on nipple
75
what stimulus causes higher brain centres to increase lactation and milk secretion?
sound of baby crying
76
what is the definition of a pre-term birth?
delivery between 24 and 36+6 weeks
77
what are the 6 main types of causes of pre-term birth?
- infection
- over-distention
- vascular
- intercurrent illness
- cervical insufficiency
- idiopathic
78
what is placental abruption
when placenta complete/partially separates from the uterus causing bleeding (fetus can be derived of oxygen)
79
what is the commonest compliation of multiple pregnancy?
pre-term labour
80
why is pre-term labour a consequence of multiple pregnancy?
over-distension of the uterus
81
what is cervical insufficiency?
a serious complication of pregnancy where the cervix opens prematurely
82
how do you estimate the height of a fetus?
fundal height- measured from pubic symphysis to fundus of uterus
83
what should you do if fundal height seems small for gestational age?
US scan to determine size of fetus
84
placental dysfunction (leading to intra-uterine growth restriction) is often secondary to what?
maternal hypertension
85
describe symmetrical growth restriction?
both head and abdomen small
86
describe asymmetrical growth restriction?
head normal size (head-sparing) and small abdomen
87
when does growth restriction have to take place for symmetrical pattern?
in early pregnancy
88
when does growth restriction have to take place for asymmetrical pattern?
in late pregnancy
89
why is there a risk of hypoxia in a growth restricted fetus during delivery?
when uterus contracts, blood supply is cut off to the baby, if baby is growth restricted they do not cope with this well
90
why is pre-eclampsia assocaited with growth restriction?
vasospasm in placental blood vessels
91
why is there reduced liquor with placental insufficiency?
kidneys are underperfused so don't produce as much fluid
92
what are the 2 main causes for reduced liquor?
placental insufficiency
| burst membranes
93
why is reduced fetal movements a sign of placental insufficiency?
baby tries to conserve energy to deal with reduced oxygen supply
94
what is carditocography?
a way of measuring the fetus's heart
95
on CTG, what indicates a good reflex reactivity of the fetal circulation?
acceleration at the start of the uterine contraction, returning to baseline
96
what does loss of baseline variability on CTG indicate?
possible asphyxia
97
what does deceleartion with lag time on CTG indicate?
possible asphyxia
98
what does umbilical arterial doppler measure?
placental resistance to flow
99
why might steroids initially improve absent end diastolic flow on doppler US of umbilical artery?
vasodilation effect
100
what must be done urgently if there is reversed end-diastolic flow on doppler US of umbilical artery
deliver baby
101
if delivering a baby below 30 weeks, why is magnesium sulphate given?
neuroprotection- reduces risk of intracranial haemorrhage
102
what is middle cerebral artery doppler used for?
to look for redirection of blood flow
103
what is polyhydramnios?
excess amniotic fluid
104
what are the 5 main causes of polyhydramnios?
- monochorionic twin pregnancy
- fetal anomaly
- maternal diabetes
- hydrops fetalis
- idiopathic
105
why can polyhydramnios lead to pre-term labour?
stretch on uterus
106
what does zygosity refer to?
number of eggs fertilised to produce twins
107
what does chorionicity refer to?
the membrane pattern of the twins
108
describe dichorionic diamniotic twins twins?
independent systems (both have their own chorion, amnion and placenta)
109
what membrane patterns can dizygotic twins lead to?
only dichorionic diamniotic
110
what membrane patterns can monozygotic twins lead to?
dichorionic diamniotic
monochorionic diamniotic
monochorionic monoamniotic
111
describe monochorionic diamniotic twins?
shared chorion and placenta
| separate amnions
112
describe monochorionic and monoamniotic twins?
shared chorion
shared placenta
shared amnion
113
if a fertilised egg splits to form monozygotic twins within 4 days of fertilisation, what pattern of membranes occurs?
dichorionic diamniotic
114
if a fertilised egg splits to form monozygotic twins from 4-8 days of fertilisation, what pattern of membranes occurs?
monochorionic diamniotic
115
if a fertilised egg splits to form monozygotic twins from 8-12 dyas of fertilisation, what pattern of membranes occurs?
monochorionic, monoamniotic
116
what is the major risk with monochorionic twins?
twin-twin transfusion syndrome
117
what is the major risk with monoamniotic twins?
cord entanglement
118
what sign is seen on ultrasound that indicates dichorionic twins?
lambda sign
119
at what gestational age do you use US to see if there are multiple pregnancies and the pattern of membranes with twins?
12-14 week scan
120
describe AFP levels with multiple pregnancies?
high
121
at what gestational age do you offer to deliver in dichorionic twins?
37 weeks
122
how often do you scan dichorionic twins and monochorionic twins?
dichorionic twins- every 4 weeks
| monochorionic twins- every 2 weeks
123
how do you treat twin-twin transfusion syndrome?
fetoscopy and ablation of connecting vessels
124
why do you put mothers on routine iron supplementation if she has a multiple pregnancy?
anaemia very common
125
how do you deliver triplets?
C section
126
how do you deliver twins?
vaginally if first baby is head first aligned (may have to progress to C section for second baby)
127
post-natally, if a mother had gestational diabetes, when should you do a oral-glucose tolerance test to ensure diabetes was only transient?
6-8 weeks post-natally
128
what is gestational diabetes?
carbohydrate intolerance resulting in hyperglycaemia with onset/first recognition during pregnancy
129
why can gestational diabetes lead to shoulder dystocia of the baby?
macrosomia with weight especially around shoulders
130
when is gestational diabetes screened for?
at booking bloods
131
when is gestational diabetes diagnosed?
GTT at 28 weeks
132
at what gestational age do you offer delivery for a pregnant lady with diabetes?
38 weeks gestation
133
why does the rate of cervical cancer incidence increase steeply until around 35 and then decrease?
due to HPV risk
134
at what stages in life does the transformational zone of the cervix chane?
menarche
pregnancy
menopause
135
what type of cells line the ectocervix?
squamous epithelium
136
what type of cells line the endocervix?
columnar epithelium
137
why can the ecocervix undero physological squamous metaplasia?
exposure to acid of the vagina- cervical erosion
138
what follicles form due to cervical erosion of the endocervix?
nabothian follicles
139
what is follicular cervicitis?
sub-epithelial reactive lymphoid follicles present in cervix
140
what is a cervical polyp?
localised inflammatory outgrowth (not premalignant)
141
what cells in the cervix does HPV infect?
epithelial cells
142
what 2 types of HPV cause 70% of all cervical cancers?
16 and 18
143
what are the 4 main risk factors for cervical intraepithelial neoplasia/cervical cancer?
- persistence of high risk HPV
- vulnerability of squamous-columnar junction in early reproductive life
- smoking
- immnosuppression
144
what three factors contribute to the increasing vulnerability of the squamous-columnar junction in early productive life?
- age at first intercourse
- long term use of oral contraceptives
- non-use of barrier contraception
145
what types of HPV cause genital warts?
6 and 11
146
describe the histological changes of HPV genital warts?
condyloma acuminatum:
papillomatous squamous epithelium with cytoplasmic vacuolation ('koilocytosis')
147
describe the histological changes of cervical intraepithelial neoplasia due to HPV infection?
epithelium remains flat but may show koilocystosis
148
what is koilocystosis?
squamous epithelium which has undergone structural changes due to HPV infection
149
what is the histology of most common type of malignant cervical tumours?
invasive squamous carcinoma
150
what is the average time from HPV infection to high graDe CIN?
6 months to 3 years
151
what is the average time from high grade CIN to invasive cancer?
5-20 years
152
if cervical intraepithelial neoplasia is asymptomatiic and not visible by naked eye- how is it detected?
cervical screening
153
describe the differences between CIN I, II and III?
I -basal 1/3 of epithelium occupied by abnormal cells
II -abnormal cells in middle 1/3 too
III -abnormal cells occupy full thickness
154
in invasive squamous carcinoma, which happens first- lymphatic or haematogenous spread?
lymphatic spread to pelvic and para-aortic nodes
155
what is the preinvasive phase of endocervical adenocarcinoma?
cervical glandular intraepithelial neoplasia (CGIN)
156
why is screening less effective for CGIN than for CIN?
more difficult to diagnose CGIN on cervical smears
157
which has a better prognosis- cervical squamous carcinoma or endocervical andenocarcinoma?
squamous carcinoma
158
which HPV type is most associated with endocervical adenocarcinomas?
HPV 18
159
what is the most important prognostic factor in vulvar invasive squamous carcinoma?
spread to inguinal lymph nodes
160
what does vulvar pagets disease arise from?
sweat glands
