Obstetrics Flashcards
What is an ectopic pregnancy?
a pregnancy which is implanted outside the uterus
not viable
Most common site for an ectopic pregnancy?
the ampulla of the fallopian tube
RFs for ectopic pregnancy?
prev ectopic pregnancy
prev PID
prev Sx to fallopian tubes (tubal ligation)
endometriosis
IUDs
IVF
older age
smoking
Presentation of ectopic pregnancy?
typically presents around 6-8wks gestation
missed period
lower abdo pain (RIF, LIF)
vaginal bleeding
pelvic tenderness
cervical excitation
shoulder tip pain (peritonitis)
Ectopic appearance on US?
empty uterus
‘blob’ sign, ‘bagel’ sign, ‘tubal ring’ sign
Ectopic pregnancy vs corpus luteum?
ectopic pregnancy will move separately from the ovary whereas corpus luteum will move with the ovary
What is Pregnancy of Unknown Location (PUL)?
where the woman has a positive pregnancy test and there is no sign of pregnancy on US
Mx of PUL?
track serum HCG after 48hrs
rise of >63% most likely indicated intrauterine pregnancy
rise of < 63% most likely indicated ectopic pregnancy
fall of >50% most likely indicates miscarriage
When should a pregnancy be visible on US?
when the serum HCG is >1500 IU/l
3 options for Mx in ectopic pregnancy?
expectant management
medical management
surgical management
What is used as medical management in an ectopic pregnancy?
methotrexate
What is used as surgical management in an ectopic pregnancy?
salpingectomy or salpingotomy (to preserve fertility if issue with the other fallopian tube)
1 in 5 risk of failure in salpingotomy
Anti-rhesus D prophylaxis given to rhesus negative women
When can expectant management be performed in an ectopic pregnancy?
follow-up possible
unruptured mass
adnexal mass <35mm
HCG level <1500
no visible heartbeat
no significant pain
When can medical management be performed in an ectopic pregnancy?
follow-up possible
unruptured
adnexal mass <35mm
no visible heartbeat
no significant pain
HCG < 5000
confirmed absence of intrauterine pregnancy on US
When can surgical management be performed in an ectopic pregnancy?
pain
adnexal mass > 35mm
visible heartbeat
HCG > 5000
How is methotrexate given in ectopic pregnancy?
IM injection into buttocks
not recommended to get pregnant for 3 months after
What site has the highest risk of rupture in an ectopic pregnancy?
isthmus of fallopian tube
What is a miscarriage?
a spontaneous termination of a pregnancy
early miscarriage - before 12wks
late miscarriage - 12-24wks
What is a missed miscarriage?
foetus is no longer alive, but the patient has not experienced any symptoms
What is a threatened miscarriage?
vaginal bleeding with a closed cervical os and the foetus is still alive
What is an inevitable miscarriage?
vaginal bleeding with an open cervical os
What is an incomplete miscarriage?
RPOC remain in the uterus after miscarriage
What is a complete miscarriage?
full miscarriage has occurred and there are no RPOC in the uterus
What is an anembryonic pregnancy?
a gestational sac is present but there is no embryo inside it
Investigation for miscarriage?
Transvaginal US
3 features of early pregnancy on US?
mean gestational sac diameter
fetal pole and crown-rump length
fetal heartbeat
When is a fetal heartbeat expected to be seen?
when the crown-rump length is 7mm or more
if not -> repeat scan in a week to confirm non-viable pregnancy
When is a fetal pole expected to be seen?
when the mean gestational sac diameter is 25mm or more
if not -> repeat scan in a week to confirm anembryonic pregnancy
Management of miscarriage?
<6 wks -> expectant management providing no RFs, repeat urinary pregnancy test after 7-10 days, no US as nothing will be seen
> 6wks -> expectant, medical or surgical
Who can receive expectant management of a miscarriage?
women without RFs for heavy bleeding or infection
repeat urinary pregnancy test 3wks after cessation of bleeding
Medical Mx of miscarriage?
oral mifepristone vaginal misoprostol (prostaglandin analogue)
Side Effects of misoprostol?
heavy bleeding
pain
vomiting
diarrhoea
Surgical Mx of miscarriage?
Manual vacuum aspiration (local anaesthetic, <10wks)
Electric vacuum aspiration (general anaesthetic)
Anti-Rhesus D prophylaxis to rhesus negative women
Management of incomplete miscarriage?
medical (misoprostol)
surgical (evacuation of RPOC)
Complication of evacuation of RPOC?
endometritis
RFs for miscarriage?
maternal age >35
prev miscarriage
obesity
chromosomal abnormalities
smoking
uterine abnormalities
prev uterine sx
antiphospholipid syndrome
coagulopathies
When to give anti-D prophylaxis to Rhesus negative women in miscarriage?
at any gestation if undergoing Sx management
at >12 wks gestation undergoing any management
DDx for vaginal bleeding in first trimester?
implantation bleed
miscarriage
ectopic pregnancy
molar pregnancy
local causes (cervix, vagina)
What is recurrent miscarriage?
three or more consecutive miscarriages
When are investigations started in regard to recurrent miscarriages?
after 3 or more first-trimester miscarriages
after 1 or more second-trimester miscarriages
Causes of miscarriage?
idiopathic (particularly in older women)
antiphospholipid syndrome
hereditary thrombophilias
uterine abnormalities
chromosomal abnormalities (parental or embryonic)
chronic histiocytic intervillositis
chronic diseases (DM, PCOS, SLE, thyroid disease)
What is antiphospholipid syndrome?
autoimmune condition causing a hypercoagulable state, resulting in miscarriage, stillbirth and thrombosis
can be secondary to SLE
Antibodies for Antiphospholipid Syndrome?
anti-cardiolipin antibodies
Lupus anticoagulants
anti-beta-2-glycoprotein-1 antibodies
Reducing risk of miscarriage in APS?
low dose aspirin + LMWH
Examples of uterine abnormalities?
uterine septum
unicornuate uterus
bicornuate uterus
didelphic uterus
cervical insufficiency
fibroids
adhesions (Asherman’s syndrome)
Investigations for recurrent miscarriage?
antiphospholipid antibodies
inherited thrombophilia screen
cytogenetic analysis (POC)
parental blood karyotyping
pelvic US
When is cervical cerclage indicated?
prev poor obstetric hx (>3 2nd trimester miscarriages)
cervical length shortening on US
symptomatic women with premature cervical dilatation and exposed fetal membranes in vagina
Complications of cervical cerclage?
bleeding
rupture of membranes
stimulation of uterine contractions
Medical TOP comprises of?
mifepristone (anti-progesterone)
misoprostol (prostaglandin analogue) 24-48hrs after
Rhesus negative women should be give anti-D prophylaxis if >10 wks
Surgical TOP comprises of?
cervical dilatation and suction of the contents of the uterus (up to 14wks)
cervical dilatation and evacuation using forceps (14-24wks)
Rhesus negative women should have anti-D prophylaxis
When to perform urine pregnancy test post-abortion?
3 weeks post-abortion
Complications of TOP?
bleeding
pain
infection
failure of termination
damage to cervix, uterus
regret
What is hyperemesis gravidarum?
NVP +
5% weight loss compared to pre-pregnancy
dehydration
electrolyte imbalance
Assessing of severity of N&V?
Pregnancy-Unique Quantification of Emesis (PUQE) Scale
RFs for hyperemesis gravidarum?
molar pregnancy (incr. bHCG)
multiple pregnancy (incr. bHCG)
obesity
first pregnancy
prev Hx
FHx
Mx of nausea and vomiting?
oral anti-emetics (prochlorperazine, cyclizine, ondansetron, metoclopramide)
admit if unable to tolerate oral fluids + anti-emetics, if >5% weight loss, if ketonuria,
if admitted -> IV/IM antiemetics, IV fluids (saline with potassium chloride), monitoring of U&Es, thiamine supplementation
Choice of fluids in cases of hyperemesis gravidarum?
IV normal saline with potassium chloride
(hypokalaemia v common)
monitor U&Es
2 types of molar pregnancy?
complete mole (1 sperm fertilise an empty ovum, then duplicates, no fetal material will form)
partial mole (2 sperm fertilise a normal ovum, it becomes a ‘triploid cell’ and splits, some fetal material may form)
Presentation of molar pregnancy?
more severe morning sickness
vaginal bleeding
increased enlargement of uterus
abnormally high hCG
thyrotoxicosis
Appearance of molar pregnancy on US?
‘snowstorm’ appearance
Snowstorm appearance on US indicates?
molar pregnancy
Mx of molar pregnancy?
evacuation of the uterus
histological examination
referral to gestational trophoblastic disease centre
monitoring of hCG
(rarely mole can become invasive and metastasise -> systemic chemo)
anti-D prophylaxis in Rhesus negative women
Other types of gestational trophoblastic diseases?
choriocarcinoma
placental site trophoblastic tumour
epithelioid trophoblastic tumour
RFs for gestational trophoblastic disease?
maternal age <20 or >35
prev GTD
prev miscarriage
use of COCP
What is Post-Partum Haemorrhage?
bleeding after the delivery of the baby and the placenta
most common cause of significant maternal haemorrhage
500ml after vaginal delivery
1000ml after c section
Categories of PPH?
minor PPH - <1000ml
moderate PPH - 1000-2000ml
severe PPH - >2000ml
primary PPH -> within 24hrs
secondary PPH -> 24hrs-12wks
Causes of PPH?
4 T’s
Tone (uterine atony)
Trauma (e.g., perineal tear)
Tissue (retained placenta)
Thrombin (bleeding disorder)
Most common cause of PPH?
uterine atony
RFs for PPH?
prev PPH
multiple pregnancy
obesity
large baby
failure to progress in second stage of labour
prolonged third stage of labour
pre-eclampsia
placenta accreta
retained placenta
instrumental delivery
general anaesthesia
episiotomy or perineal tear
Prevention of PPH?
treat anaemia in antenatal period
empty bladder during labour
active management of third stage (IM oxytocin)
IV tranexamic acid in C section in high risk patients
Initial Mx of PPH?
ABCDE
lie flat, keep warm
bloods for FBC, U&E, coag
Cross match 4 units
IV fluid and blood resuscitation as required
O2 (regardless of sats)
FFP if clotting abnormalities or after 4 units
Treatment to stop bleeding in PPH?
mechanical
medical
surgical
Mechanical interventions in PPH?
bimanual compression, rubbing the uterus (stimulate contraction)
bladder catheterisation
Medical interventions in PPH?
oxytocin (slow injection followed by 40 units in 500mls infusion)
ergometrine (IM or IV, contraindicated in HTN)
IM carboprost (prostaglandin analogue, caution in asthma)
misoprostol (sublingual)
tranexamic acid (IV, antifibrinolytic)
Sx Management of PPH?
intrauterine balloon tamponade
B-Lynch suture
uterine artery ligation
hysterectomy
Causes of secondary PPH?
RPOC
infection (endometritis)
Investigations of secondary PPH?
US for RPOC
endocervical and high vaginal swabs for infection
RFs for uterine atony?
maternal age >40
BMI >35
Asian ethnicity
uterine over-distension (multiple pregnancy, polyhydramnios, fetal macrosomia)
labour (failure to progress in second stage, prolonged third stage)
placental problems (placental abruption, placenta accreta spectrum)
prev PPH
What is umbilical cord prolapse?
obstetric emergency
when the umbilical cord descends below the presenting part of the foetus and through the cervix into the vagina, after the rupture of the membranes
presents with non-reassuring fetal heart trace
Biggest complication associated with cord prolapse?
fetal hypoxia
due to compression of the cord by the presenting part of the foetus + vasospasm of the cord when exposed to room air
Risk Factors for Cord Prolapse?
breech presentation
unstable lie
artificial rupture of membranes
polyhydramnios
prematurity
Mx of Cord Prolapse?
avoid handling the cord (could cause vasospasm)
keep cord warm and wet
push the presenting part back inside
left lateral position
knee-chest position
tocolytics
emergency c section (unless vaginal delivery imminent -> instrumental delivery)
What is cord presentation?
the presence of the cord between the presenting part and the cervix
with or without intact membranes
What is shoulder dystocia?
obstetric emergency
when the anterior shoulder becomes impacted on the pubic symphysis and can’t be delivered
less commonly the posterior shoulder becomes impacted on the sacral promontory
Risk Factors for Shoulder Dystocia?
Pre-Labour:
previous shoulder dystocia
macrosomia
diabetes
maternal BMI >30
post-term pregnancy
advanced maternal age
short stature
IOL
Labour:
prolonged 1st stage
secondary arrest
prolonged 2nd stage
augmentation of labour with oxytocin
assisted vaginal delivery
Signs of shoulder dystocia?
difficulty delivering head or chin
failure of restitution
‘turtle’ sign
What to avoid when managing shoulder dystocia?
avoid downwards traction on baby’s head (incr. risk of brachial plexus injury)
do not apply fundal pressure (incr. risk of uterine rupture)
Mx of shoulder dystocia?
declare obstetric emergency
advise mother to stop pushing
manoeuvres
Manoeuvres for shoulder dystocia?
McRoberts manoeuvre
Suprapubic pressure
Episiotomy (for access)
Rubin’s manoeuvre
Woodscrew manoeuvre
Delivery of posterior arm
Gaskin manoeuvre
Zavanelli manoeuvre
fracture clavicle
symphysiotomy
Complications of shoulder dystocia?
foetal hypoxic brain injury (cerebral palsy)
fetal brachial plexus injury (Erb’s palsy, Klumpke palsy)
fetal clavicle or humerus fracture
maternal perineal tear (3rd or 4th)
maternal PPH
What is aortocaval compression syndrome?
compression of the abdominal aorta and the inferior vena cava by the gravid uterus when a pregnant women is supine
How does aortocaval compression syndrome present?
hypotension
loss of consciousness
fetal demise rarely
Positioning to avoid aortocaval compression syndrome?
left lateral position
30 degrees on the bed
Vaccines offered to pregnant women?
pertussis from 16wks
influenza
Covid
no MMR -> live vaccine, give postnatally if not vaccinated already
Investigations at the booking visit?
weight, height, BMI
BP
urinalysis
FBC
blood group, antibodies and rhesus D status
screen for thalassemia
HIV
Hep B
syphilis
Risk assessment at booking visit?
Rhesus negative (anti-D)
GDM (OGTT)
fetal growth restriction (serial growth scans)
VTE (prophylactic LMWH)
pre-eclampsia (low dose aspirin)
What is SGA?
a foetus that measures below the 10th centile for their gestational age
How is fetal size assessed?
estimated fetal weight
fetal abdominal circumference
biparietal diameter
femur length
head circumference
What is severe SGA?
less than 3rd centile for gestational age
Causes of SGA?
incorrect dates
constitutionally small
fetal growth restriction
Causes of fetal growth restriction?
fetal causes:
chromosomal abnormalities
structural abnormalities
fetal infection (TORCH)
maternal causes:
PET
GDM
maternal chronic illnesses
smoking
alcohol
drugs
medications (anti-epileptics, DMARDs)
oligohydramnios:
ROM
renal agenesis
Complications of FGR?
fetal death or stillbirth
birth asphyxia
neonatal hypothermia
neonatal hypoglycaemia
Monitoring of fetal growth in high risk patients?
serial growth scans
growth velocity
Doppler umbilical artery
amniotic fluid volume
LGA is defined as?
estimated fetal weight is above the 90th centile
Causes of LGA?
incorrect dates
multiple pregnancy (if haven’t engaged with ANC)
molar pregnancy
constitutional
fetal causes
maternal causes
polyhydramnios
chorioangioma
Foetal causes of LGA?
constitutional
hydrops fetalis
Maternal causes of LGA?
GDM
maternal obesity
rapid weight gain
fibroids
Causes of polyhydramnios?
oesophageal atresia
congenital diaphragmatic hernia
duodenal atresia
TTTS
macrosomia
Causes of APH?
placenta praevia
placental abruption
vasa praevia
uterine rupture
bloody show
cervical ectropion
cervical polyps
trauma to vagina or cervix
Gestational HTN definition?
New HTN (>140/90) in a woman of >20wks gestation, without proteinuria
Pre-eclampsia definition?
pregnancy-induced HTN + evidence of organ damage i.e., proteinuria
RFs for pre-eclampsia?
pre-existing HTN
prev. pre-eclampsia
existing autoimmune conditions
diabetes
CKD
> 40
BMI>30
multiple pregnancy
first pregnancy
FHx
10yrs since prev. pregnancy
Prophylaxis against pre-eclampsia?
low-dose aspirin from 12wks till birth
Symptoms of pre-eclampsia?
usually asymptomatic -> symptoms are red flag
headache
visual disturbances
N&V
upper abdo or epigastric pain
oedema
brisk reflexes
Diagnosis of pre-eclampsia?
HTN
+
proteinuria
or
organ dysfunction
or
placental dysfunction
Mx of pre-eclampsia?
women at risk given low-dose aspirin
monitoring of BP, urinalysis and symptoms
medical mx
Medical Mx of pre-eclampsia?
labetalol
nifedipine
methyldopa
IV mag sulphate during labour and till 24hrs after
What is HELLP syndrome?
severe form of pre-eclampsia
pre-eclampsia
haemolysis
elevated liver enzymes
low platelets
Presentation of obstetric cholestasis?
itching, particularly of palms of hands and soles of feet
fatigue
dark urine
pale stools
jaundice
**no rash
Mx of obstetric cholestasis?
ursodeoxycholic acid
emollients and anti-histamines
planned delivery at 37wks to reduce risk of stillbirth (due to build-up of bile acids)
Placenta praevia definition?
where the placenta is attached to the lower portion of the uterus, below the presenting part
low-lying uterus -> within 20mm of cervical os
placenta praevia -> placenta is over the cervical os
Complications of placenta praevia?
APH
emergency c section
emergency hysterectomy
maternal anaemia and transfusions
preterm birth
low birth weight
stillbirth
RFs for placenta praevia?
previous placenta praevia
previous c sections
previous uterine sx
older maternal age
maternal smoking
multiple pregnancy
structural uterine abnormalities (e.g., fibroids)
assisted reproduction (IVF)
Mx of placenta praevia?
repeat US at 32wks and 36wks
planned c section from 36-37wks
emergency c section if APH or prem labour
corticosteroids if before 34wks
What is vasa praevia?
where the foetal blood vessels are exposed and placed over internal cervical os, before the presenting part of the fetus
RFs for vasa praevia?
low-lying placenta
IVF
multiple pregnancy
Mx of vasa praevia?
emergency c section
if foetal death -> vaginal delivery
What is placental abruption?
when the placenta separates from the wall of the uterus during pregnancy
significant cause of APH
RFs for placental abruption?
prev. placental abruption
PET
bleeding early in pregnancy
trauma
multiple pregnancy
FGR
multiparity
incr. maternal age
smoking
cocaine or amphetamine use
Presentation of placental abruption?
sudden onset severe continuous abdo pain
APH
shock (hypotension, tachycardia)
‘woody’ uterus
fetal distress on CTG
APH severity?
spotting
minor = <50ml
major = 50-1000ml
massive = >1000ml or signs of shock
What is concealed abruption?
where the cervical os remains closed, and thus the bleeding occurs within the uterus
blood loss can be severely underestimated
Mx of placental abruption?
ABCDE
2 wide bore cannulas
Bloods (FBC, coag)
Cross match 4 units
fluid and blood resuscitation
CTG
monitoring of mother
emergency c section
RFs for pre-term birth?
uterine: PPROM, polyhydramnios, infection, uterine anomalies
placental: insufficiency, abruption, APH
maternal: previous hx of pre-term, cervical sx, pre-eclampsia
social: extremes of age, nutrition, smoking, drug abuse, low socio-economic groups
