Flashcards in Obstetrics 1 Deck (120):
What USS measurement is most useful for fetal gestation estimation earlier on in pregnancy (9-14 weeks, so for booking scan)?
Crown rump length
What fetal measurements are used later on in pregnancy, so from 14 weeks onwards?
Head circumference, fetal abdominal circumference
What is parity?
Number of potentially viable births >24 weeks
Para = x + y
x = number of births over 24 weeks, stillbirth or normal etc.
y = miscarriages, ToPs
What is gravidity?
Number of times been pregnant including current pregnancy
E.g. G6 P3+2
LIe and liquor - feel all round
Rate and auscultation
When is the uterus first palpable during pregnancy? When might this be earlier?
Earlier in multiple pregnancy
At what gestation is fundus of uterus roughly umbilical level? What implications does this have for SFH?
From that point, SFH roughly correlates to gestation +/- 2cm
Discuss engagement of fetal head?
5/5 palpable = fully above pelvic brim, not engaged
3/5 = generally engaged
How many routine antenatal visits would a nulliparous woman have?
How many routine antenatal visits would a multiparous woman have?
Normal folic acid supplementation?
400micrograms per day til > 12 weeks
Specific examples of food poisoning that can affect pregnant woman badly?
Listeriosis - milk
Salmonella - chicken, eggs
When should booking visit be done?
What is the combined test for Down's syndrome screening?
What infections need to be screened for at booking visit?
BBVs e.g. Hep B, HIV
STIs - chlamydia, BV, gonorrhoea
What non-infectious conditions need to be enquired about at booking visit?
Haemaglobinopathies and anaemia
Pre existing disease, e.g. Cardiac
When is the anomaly scan done? What are you looking for?
NTDs +/- fetal echocardiography
When is rhesus anti-D routinely given prophylactically during pregnancy?
28 weeks and then 32 weeks
What is assessed at 36 week visit?
USS for fetal presentation - offer ECV if breech
When does early morning sickness often resolve in normal pregnancy?
By end of first trimester, 16-20 weeks
What is Naegele's rule?
EDD = LMP + 9 months + 7 days
What yeast infection are pregnant women more susceptible to?
5 blood tests associated with Down's syndrome screening?
What USS marker is used in Down's syndrome screening?
What is amniocentesis and when is the earliest it should be done?
US guided removal of amniotic fluid
Earliest 15 weeks
What 3 types of disease can amniocentesis be used to investigate?
Which has a higher miscarriage rate, amniocentesis or CVS?
What is chorionic villous sampling? Earliest it can be done?
Trophoblast (placental) biopsy
Earliest 11 weeks
What is CVS especially good at detecting?
2 major RFs for Down's syndrome?
High maternal age
Previously affected baby
What signs of Down's syndrome may be visible on USS?
Cardiac abnormality (tricuspid regurge)
Short nasal bone
What are the 4 constituents which constitute the combined test for Down's syndrome?
What blood markers are raised in Down's syndrome screening?
What blood markers are reduced in Down's syndrome screening?
What is Edwards syndrome?
What is trisomy 18?
What is trisomy 13?
What is patau's syndrome?
What is Klinefelters syndrome?
47 XXY - infertile males
What chromosomal abnormality commonly causes infertility in males?
What is turners syndrome?
45XO - infertile females
What chromosomal abnormality commonly causes infertility in females?
What blood marker is raised in NTDs?
What congenital abdominal wall defect often occurs in the absence of any other abnormalities?
How do congenital GI defects often present antenatally?
Polyhydramnios - impaired swallow
What GI defect is common with Down's syndrome?
What is fetal hydrops?
Fluid accumulation in 2 or more fetal compartments e.g. Skin oedema and pleural effusion
What are the 2 classifications of causes of fetal hydrops?
Immune or non-immune
Major immune cause of fetal hydrops?
Ab immunisation incl Rhesus
5 main non-immune causes of fetal hydrops?
Chromosomal e.g. Down's
Structural - pleural effusions
Cardiac including arrhythmias
Anaemia - PV B19 infection, a thalassaemia
Twin-twin transfusion syndrome
Maternal causes of polyhydramnios?
Fetal causes of polyhydramnios?
Upper GI obstruction
What might be the cause of polyhydramnios in multiple pregnancy?
Potential problems caused by polyhydramnios?
Abnormal lie and presentation
What medication can reduce fetal fluid output and therefore ease polyhydramnios?
What are the major long term complications of maternal CMV infection?
Severe neurological sequelae e.g. Hearing, visual, mental impairment
What can early pregnancy rubella infection cause?
Can women have the rubella vaccine in pregnancy?
No - it's a live vaccine
What 2 implications can maternal BV have on pregnancy?
What can maternal chlamydia cause in pregnancy?
Implications of GBS infection in pregnancy?
Often asymptomatic bacteruria
However can cause PPROM, neonatal sepsis (meningitis or pneumonia)
Implications of HBV infection in pregnancy?
Vertical transmission is possible and 90% of infected neonates become chronic carriers
5 major antenatal risks of maternal HIV infection?
What should be avoided postnatally in HIV infected mothers?
What bacteria is traditionally responsible for puerperal sepsis?
GAS (strep pyogenes)
What can GAS infection cause in mothers?
4 early pregnancy events which may be 'sensitising' in terms of Rhesus factor?
Procedure related to breech which may be a sensitising event?
When is rhesus screening acted upon in pregnancy?
To any rhesus negative woman:
Within 72 hours of any potentially sensitising event including delivery if neonate positive
At 28 weeks
Other important rhesus antibodies besides D?
C, E and Kell
6 differentials for antepartum haemorrhage?
Genital tract pathology
Vasa praevia rupture
What is an antepartum haemorrhage?
Bleeding from the genital tract > 24 weeks
4 RFs for placenta praevia?
Presentation of placenta praevia?
Intermittent painless bleeds which may become constant and heavy over several weeks
What is placenta accreta? What normally causes it?
Non-separation of the placenta from uterine wall at birth
Often due to scarred uterus - prev CS
If a placenta is found to be low lying at 20 weeks, when should it be rescanned to exclude placenta praevia?
5 RFs for placental abruption?
Pre-eclampsia or maternal HTN
Multiple pregnancy and multiparity
How does placental abruption present?
Painful bleeding PV, degree of which doesn't necessarily reflect extent of bleed
What is the difference between a concealed and revealed placental abruption?
Concealed = pain no blood
Revealed = pain and blood
What may be found on obstetric exam in placenta praevia vs abruption?
Praevia - abnormal lie, breech, high fetal head
Abruption - tender, woody hard uterus
3 genital tract pathologies that may cause antepartum haemorrhage?
What is the typical presentation of vasa praevia rupture?
Painless, moderate PV bleed around time of amniotomy or spontaneous ROM
What might a painless bleed just after amniotomy or ROM indicate?
Vasa praevia rupture
What is the normal lie in pregnancy?
What 2 presentations can result from a longitudinal lie?
In what group of babies is abnormal lie the biggest problem?
What are the 3 groups of reasons for an abnormal lie or breech?
Too much room to move
No room to move
Factors preventing engagement
'Too much room to move' causes of abnormal presentation?
High parity (lax uterus)
What does having too much room to move in the uterus often result in?
An unstable lie
'No turning' causes of an abnormal lie of breech?
Uterine abnormality e.g. Fibroids
Factors preventing engagement resulting in an abnormal lie or breech?
What 2 things can an unstable lie suggest?
Lax uterus (multiparity)
Complications of abnormal lie or breech?
Failure to progress in labour
Umbilical cord prolapse
What 2 things need to be excluded first when investigating abnormal lie at term?
3 types of breech?
What type of breech is most common?
2 RFs for breech presentation?
What symptom is relatively common in breech?
What technique is used to turn round a breech baby?
When can ECV be done after?
What 2 things need to be done straight after ECV?
Give anti D
Do a CTG
What 2 things are used to aid ECV?
Give a uterine relaxant (tocolytic)
What is the purpose of doing an ECV?
To reduce the need for CS or vaginal breech delivery
In what 4 conditions is ECV less likely to work?
5 major contraindications to ECV?
If subsequent vaginal delivery contraindicated e.g. Placenta praevia
Is a previous CS a contraindication to ECV?
Is a CS or vaginal breech delivery safer?
Between what gestations is defined as preterm delivery?
Before what gestation do the majority of problems occur in preterm delivery?
2 major metabolic complications of prematurity?
5 conditions that are more common as a result of prematurity?
Major maternal complication of preterm labour?
Infection - endometritis
In the castle analogy, what are the 6 mechanisms of preterm labour?
Too many defenders
Defenders jump out
Poor castle design
Castle walls are weak
Attackers get through walls
Attackers get in from elsewhere
Castle analogy: too many defenders?
Castle analogy: defenders jump out?
Fetal survival response - fetal distress
Castle analogy: poor castle design?
PMH of premature labour
Castle analogy: weak walls?
Cervical incompetence e.g. Following LLETZ
Castle analogy: enemy breaks down walls
Infection which may be us clinical
BV, GBC, Trichomonas, chlamydia
Chorioamnionitis - offensive liquor