Obstetrics Flashcards
What is ectopic pregnancy and where does it commonly occur?
When a pregnancy implants outside of uterus.
MC - fallopian tubes (ampulla followed by isthmus, fimbria)
Other: abdomen, ovary, cervix
What are the RF for ectopic pregnancy?
Previous hx of ectopic pregnancy, PID, damage to fallopian tubes, STI’s
IUD (coils)
Endometriosis
Older age >35 yrs
Smoking
Sx for ectopic pregnancy and which week gestation do the Sx usually begin?
6-8 week gestation
Vaginal bleeding - dark brown colour
Missed period
Unilateral lower abdominal pain + tenderness - can lead to shoulder tip pain if severe due to irritation of phrenic vein
Cervical motion tenderness (bi-manual examination)
LOC
Ix and findings for ectopic pregnancy
Pregnancy test - B-hCG levels - both in urine and and serum
FBC - to detect blood loss
Transvaginal USS (yolk sac on fallopian tube, empty uterus or fluid filled uterus)
Tx for ectopic pregnancy
Immediate termination - watch hCG levels if it’s not decreasing then active management:
- Expectant tx (natural termination but hCG <1500)
- Methotrexate (folic acid antagonist therefore targets developing cells from producing)
- 1st line - salpingectomy (fallopian tube + ectopic pregnancy removal) or salpingostomy
What are the requirements for giving methotrexate in ectopic pregnancy and what is it’s side effects?
Requirements:
low hCG levels < 5000
Confirmed absence of intrauterine pregnancy
SE
Teratogenic
N+V
Vaginal bleeding
Abdominal pain
Stomatitis
What is postpartum haemorrhage and what would be classified as a PPH according to blood loss?
Loss of blood after delivering baby + placenta
Classified as PPH if:
* 500ml blood loss - post vaginal delivery
* 1000ml blood loss - post c-section
What is classified as:
1. Minor PPH
2. Major PPH: further classified into moderate and severe
3. Primary PPH
4. Secondary PPH
- Minor - <1000ml blood loss
- Major - >1000ml blood loss:
Moderate - 1000-2000ml blood loss
Severe - >2000ml blood loss - Primary - occurs within 24hrs of birth
- Secondary - occurs after 24hrs of birth up to 12 wks post birth
Causes of PPH? (4)
Remember 4 T’s
* Tone - uterine atony
* Trauma - perineal tear
* Tissue - retained placenta
* Thrombin (clotting disorders) - extreme blood loss
RF for PPH (6)
Previous PPH
Perineal tear
Multiple pregnancies
Obesity
Large baby
Pre-eclampsia
Retained placenta
Instrumental delivery
Placenta accreta
Preventative measures for PPH?
Tx anaemia before birth
Empty bladder - full bladder can supress uterine contractions
Active 3rd stage of labour - IM oxytocin post birth - stimulate uterine contractions
Tx of PPH to stop bleeding:
1. Mechanical
2. Medical
3. Surgical
- Mechanical
Uterus rub
Catheterisation - Medical (meds to stimulate uterine contractions)
Oxytocin, ergometrine, carboprost (CI - asthma) - Surgical
Intrauterine balloon tamponade
B-lynch suture
Hysterectomy
What is secondary PPH, cause and what is the management?
Bleeding 24hrs up to 12 wks post birth
Cause: remained product of conception or infection
Tx: surgical or abx for infection
What is placenta accreta spectrum?
When placenta implants deeper than endometrium layer therefore difficult to separate post birth
What are the 3 layers of the uterine wall and where does placenta usually attach to?
- Inner layer - endometrium (connective tissue and blood vessels)
- Middle layer - myometrium (smooth muscle)
- Outer layer - perimetrium (serous membrane)
Placenta = endometrium
Define:
1. Superficial placenta accreta
2. Placenta increta
3. Placenta percreta
- Attaches surface of myometrium
- Implants deep into myometrium
- Implants past myometrium and perimetrium
RF for placenta accreta (4)
Previous placenta accreta
Previous C-section
Previous endometrial curettage procedures for miscarriage or abortion
Low-lying placenta
Placenta praevia
> maternal age
Sx and Ix for placenta accreta diagnosis
Sx: usually aSx but causes PPH
Ix: USS detects + MRI scan to investigate or can be diagnosed post birth
Tx of placenta accreta
If found before birth - Plan delivery at 35 - 36 weeks gestation + give antenatal steroids to mature foetal lung
If found post-birth:
1st line - hysterectomy
Uterus preserving surgery
Expectant management - risk of infection
What are the 3 main causes of antepartum haemorrhage?
Placenta praevia
Vasa praevia
Placental abruption
What is placenta praevia? How does it differ from low lying placenta?
When the placenta covers the internal cervical os, under the foetus.
Low lying placenta - when the placenta is 20mm away from the internal cervix os.
What are the risks of having placental praevia? (3)
Antepartum haemorrhage
Stillbirth
Preterm birth
Emergency c-section and hysterectomy
Maternal anaemia
RF for placenta praevia (3)
Previous c-section or placenta praevia
> maternal age
maternal smoking
Uterine abnormalities (fibroids)
Assisted reproduction (IVF)
Sx and Ix for placenta praevia
aSx but bright red painless vaginal bleeding during pregnancy (especially later on in pregnancy at or over 26 weeks)
Ix - USS at 20 week scan
Transvaginal USS repeated at 32 and 36 weeks
Management of placenta praevia
Increased risk of pre-term pregnancy - give corticosteroids to mature foetal lungs
Planned c-section
What is placental abruption?
When the placenta detaches from the endometrium. Separation from site can cause excessive bleeding leading to antepartum haemorrhage.
RF for placental abruption (4)
Previous placental abruption or c-section
> maternal age
Smoking
Cocaine use
Multiple pregnancies
Multi gravida
Pre-eclampsia
Trauma (i.e. domestic abuse)
Sx of placental abruption
Sudden onset continuous severe abdominal pain
Vaginal bleeding
Shock (tachycardic and hypotension)
Woody abdomen on palpation
What is concealed abruption?
When the cervix os is blocked therefore bleeding is contained within uterine walls.
Mx of placental abruption
Induce labour initially and attempt vaginal delivery if not then emergency c-section
What is vasa praevia?
When the foetal vessels are within the foetal membranes (chorioamniotic membranes) and travel across the internal cervical os.
Describe pathophysiology of vasa praevia:
1. What does the foetal vessel consist of?
2. Where are the foetal vessels usually located? How is it protected? How does it change in vasa praevia?
- two umbilical arteries and single umbilical vein
- Usually located within umbilical cord and are always protected by the cord which contains Wharton’s jelly or placenta. In vasa praevia the foetal vessels are exposed. It can then travel through chorioamniotic membranes and pass across cervical os
What are the two types of vasa praevia?
Type 1 - the foetal vessels are exposed as a velamentous umbilical cord (a condition where the umbilical cord inserts into the foetal membranes instead of the placenta)
Type 2 - the foetal vessels are exposed as they travel to an accessory placental lobe
RF for vasa praevia (3)
Low lying placenta
IVF pregnancy
Multiple pregnancy
Sx for vasa praevia
Antepartum haemorrhage, with bleeding during 2nd/3rd trimester of pregnancy
Pulsating fetal vessels are seen in the membranes through the dilated cervix during labour
Management of vasa praevia
If aSx:
Corticosteroids (from 32 wks to develop foetus lungs)
Elective C-section
If symptomatic:
Emergency c-section
What is cord prolapse?
When the umbilical cord descends below the presenting part of the fetus and through the cervix into the vagina, after rupture of the fetal membranes.
Cord prolapse diagnosis?
Sx of fetal distress on the CTG.
A prolapsed umbilical cord can be diagnosed by vaginal examination.
Management of cord prolapse
Emergency c-section
What is pre-eclampsia?
New onset htn that occurs from 20 weeks gestation associated with end organ damage and proteinuria.
BP of > 140/90
What is the difference between pre-eclampsia and gestational (pregnancy-induced) hypertension?
Gestational htn is increased BP without proteinuria whereas pre-eclampsia is with organ damage + proteinuria.
What is eclampsia?
Seizures (tonic clonic seizures) that occur as a result of pre-eclampsia
Describe pathophysiology of pre-eclampsia
Hint: What is the name of the artery? How does damage to that artery cau
Spiral arteries are located in placenta → normally dilated → inc. blood supply to foetus
In pre-eclampsia → abnormal spiral arteries → dec. placental perfusion:
* In foetus → blood supply decreases → intrauterine growth restriction or foetal demise
* In mother → inflammatory response → proteins are released → endothelial damage → leads to:
1. Inc. permeability → oedema (in legs, hands, cerebral)
2. Thrombin formation (HELLP syndrome)
3. Na+ retention in kidney → kidney damage → proetinuria
4. BV narrowing → inc. BP
RF for pre-eclampsia (5)
High RF:
* Pre-existing htn
* Autoimmune cdtns
* Diabetes
* CKD
Moderate RF:
* >40 yrs
* >35 BMI
* Smoking
* First pregnancy or multiparity
* Fhx
Sx for pre-eclampsia
Oedema
Headache
Visual disturbance
Dizziness
N+V
Upper abdo pain (due to liver swelling)
Brisk reflexes
Diagnosis of pre-eclampsia
Measure BP → >140/90
Urine dipstick → protein
FBC and U&E’s
Management of pre-eclampsia
- Prophylaxis → aspirin (given from 12 weeks)
- If pre-eclampsia:
1. Labetolol (1st line)
2. Nifedipine (2nd line)
3. Methyldopa (3rd line)
Fluid restriction during labour
Tx of eclampsia
IV Magnesium Sulphate
What is the HELLP syndrome?
Haemolysis
Elevated Liver enzyme
Low Platelet
Severe form of pre-eclampsia
In FBC look for haemolytic anaemia, liver enzymes and platelet levels
Define instrumental delivery and what are the different types
Vaginal delivery assisted by the use of forceps or ventouse suction to aid delivery
- Venthouse - suction cup attached to a cord
- Forceps - Two metal tongs
What are the indications for an instrumental delivery?
Maternal exhaustion
Foetal position
Foetal distress
Failure to progress
Risks of an instrumental delivery?
Both to mother and baby
Mother:
PPH, episiotomy, perineal tear, anal sphincter injury
Baby:
* Cephalohaematoma - by venthouse suction
* Facial nerve palsy - by forceps
Which nerves could be affected by an instrumental delivery?
Bonus points if youknow how injury to these nerves affects the legs.
Femoral nerve - affects patella reflexes, knee extension, numbness to anterior thigh and middle lower leg
Obturator nerve - affects hip adduction and numbness to medial thighs
What tx is given after an instrumental delivery?
Hint: it’s to reduce risk of infection
Co-amoxiclav
What are some causes of an obstructed labour? (3)
- Foetal malpresentation - breech or transverse presentation
- Foetal macrosomia
- Maternal pelvic abnormalities
- Uterine dysfuction
- Multiparity
- Prolonged labour
Describe factors that cause Intrauterine Growth Restriction (IUGR)
- Maternal Factors
- Foetal Factors
- Placental Factors
1. Maternal:
- BMI (i.e. poor weight gain for pregnancy)
- Co-morbidities (diabetes, htn, anaemia, CVD, coeliacs, etc)
- Smoker, alcohol, substance abuse
- Structural uterine malformations
2. Foetal:
- Chromosomal defects
- Multiple pregnancy
- Vertically transmitted infections (i.e. rubella, CMV)
3. Placental:
- Utero-placental insufficiency
- Pre-eclampsia
Sx of IUGR
IUGR = Intrauterine Growth Restriction
Reduced foetal movement
Abnormal fundalheight for gestation week
Complications like stillbirth and pre-eclampsia
Ix for IUGR
IUGR = Intrauterine Growth Restriction
USS to assess foetal growth, volume of amniotic fluid
Doppler to assess blood flow
Biophysical profile
Mx of IUGR
IUGR = Intrauterine Growth Restriction
Monitor foetal growth
Early delivery if foetal distress noted
What is a uterine rupture?
Describe the difference between a complete and incomplete rupture.
Rupture of the myometrium layer
1. Incomplete rupture = only myometrium tears, perimetrium stays intact
2. Complete rupture = Perimetrium tears, so uterus contents released into peritoneal cavity. This is an Emergency as baby could be released into peritoneal cavity which increases mortality and morbidity of baby.
RF for uterine rupture (4)
VBAC (vaginal birth after c-section)
Previous uterine surgeries
Increased age
Higher BMI
High parity
Induction of labour
Oxytocin use
Sx for uterine rupture
Unwell mother
Abnormal CTG
Abdominal pain
Vaginal bleeding
Ceasing of uterine contractions
Hypotension
Tachycardic
LOC
Mx for uterine rupture
EMERGENCY C-SECTION!!
Define rupture of membrane
Amniotic sac is ruptured
At which week gestation is a baby considered premature (preterm)?
Before 37 weeks gestation
Prophylaxis of preterm labour?
Who is prophylaxis offered to?
- Vaginal progesterone - via gel or pessary as progesterone protects pregnancy
- Cervical cerclage - stitch put into cervix opening taken out during labour or at term
Prophylaxis is offered to women with a cervix shorter than 25mm and between 16 and 24 weeks gestation.
Preterm Prelabour Rupture of Membranes
- Definition
- Ix
- Tx
- Rupture of amniotic sac which releases amniotic fluid before 37 weeks gestation
- Speculum or IGFBP-1 (enzyme found in high concentrations in amniotic fluid)
- Prophylactic abx (erythromycin to prevent chorioamnionitis) + possible induction of labour
Preterm Labour with Intact Membranes
- Definition
- Ix
- Tx
- Regular, painful contraction + cervical dilation without amniotic sac rupture
- USS
- Tx:
- Foetal CTG
- Tocolysis w/ Nifedipine
- Maternal corticosteroids
- IV magnesium sulfate
- Delayed cord clamping
- Tocolysis involves using medications to stop uterine contractions. It is only used as a short term measure (i.e. less than 48 hours).
- Nifedipine (tocolysis) is a calcium channel blocker that suppresses labour.
- Corticosteroids helps to develop the fetal lungs and reduce respiratory distress syndrome after delivery.
- IV magnesium sulfate helps protect the fetal brain during premature delivery. It reduces the risk and severity of cerebral palsy. Given within 24 hours of delivery.
What does rhesus status mean?
Whether someones blood group is +ve or -ve
What does it mean if someone is rhesus +ve or -ve?
Rhesus +ve = Rhesus antigen on RBC
Rhesus -ve = No rhesus antigen on RBC
Describe the pathophysiology behind how immune system deals with rhesus incompatibility.
What would happen if mum is rhesus -ve and baby is rhesus +ve
- If someone is rhesus +ve → antigen present → body’s immune system recognises it → no attack happens
- BUT if someone is rhesus -ve → but comes across antigen → body recognises it as foreign pathogen → immune system attacks → Anti-D antibodies released
Therefore in context of pregnancy:
* If mum rhesus +ve → no problem → won’t attack baby’s RBC’s
* If mum rhesus -ve → comes into contact with baby’s blood (+ve) → produces ab’s to attack the foreign antigen:
If this happens in first baby → nothing will happen to baby → mum just attacks the foreign antigen and creates ab’s that stays in her immune system
HOWEVER, in future pregnancies → ab’s previosuly created → cross placental membrane → attack baby’s RBC’s → haemolysis → can cause permanent brain damage and learning disabilities.
Define sensitisation events and give some examples. (4)
Events which cause foetal blood to cross the placenta into the maternal circulation and thus these are indications for anti-D prophylaxis.
Examples of sensitisation events include:
* Antepartum haemorrhage
* Placental abruption
* Abdominal trauma
* Intrauterine death, miscarriage or termination
* Ectopic pregnancy
* Delivery (normal, instrumental or caesarean section)
Mx of rhesus negative mum.
Anti-D Ig’s is given to all non-sensitised rhesus negative mothers at 28 weeks
What is puerperal psychosis?
A severe mental illness that suddenly starts in the days or weeks after having a baby. They can include mania, depression, confusion, hallucinations and delusions.
What is the definition of miscarriage?
Loss of pregnancy prior to 24 wks gestation.
Sx of miscarriage?
- Vaginal bleeding
- Pain - worse than usual period pain
- Vaginal tissue loss
Describe the following different types:
1. Threatened miscarriage
2. Inevitable miscarriage
3. Complete miscarriage
4. Incomplete miscarriage
5. Missed miscarriage
- Some mild sx of bleeding with foetus retained within uterus as cervical os is closed.
- Heavy bleeding + pain where foetus is currently intrauterine but cervical os is open.
- Intrauterine pregnancy which has now fully miscarried with all products of conception expelled.
- When miscarriage has began but products of conception remain and not completely cleared.
- Uterus still contains foetal tissue but foetus no longer alive.
Mx of miscarriage?
- Expectant mx: Allow natural expulsion of conception products
- Medical mx: Misoprostol
- Surgical mx: Dilatation and curettage
D&C = surgical procedure where cervix is dilated so that endometrium can be scraped with a curette (spoon-shaped instrument) to remove abnormal tissues.
What medications are used for medical termination of pregnancy?
- Mifepristone = blocks progesterone required for preggo
- Misoprostol = cx smooth muscle contractions resulting in uterine content expulsion
What are causes of macrosomia? (3)
- Gestational diabetes
- Previous macrosomia
- Maternal obesity
- Male baby
- Overdue
What are the risks of macrosomia? (4)
Note both to mother and baby
To mother:
* Shoulder dystocia
* Perineal tears
* Instrumental delivery or c-section
* PPH
* Failure to progress
To baby:
* Birth injury (fetal distress and hypoxia)
* Neonatal hypoglycaemia
* Obesity in childhood
* T2 diabetes in adulthood
Ix for a large for gestational age baby?
USS - exclude polyhydramnios
Oral glucose tolerance test - gestational diabetes
Define the following terms:
* Monozygotic
* Dizygotic
* Monoamniotic
* Diamniotic
* Monochorionic
* Dichorionic
- Monozygotic: identical twins (from a single zygote)
- Dizygotic: non-identical (from two different zygotes)
- Monoamniotic: single amniotic sac
- Diamniotic: two separate amniotic sacs
- Monochorionic: share a single placenta
- Dichorionic: two separate placentas
How would you determine the type of twin (Dichorionic diamniotic vs Monochorionic diamniotic) on an USS?
- Dichorionic diamniotic = lambada sign or twin peak sign
- Monochorionic diamniotic = T sign
Risks of a multiple pregnancy (e.g. twin pregnancy)? (4)
Both to mother and babies
To mother:
* Anaemia
* Polyhydromnios
* Htn
* PPH
* Instrumental or C-section
To fetuses:
* Miscarriage
* Stillbirth
* Fetal growth restriction
* Twin-twin transfusion syndrome
What is twin-twin transfusion syndrome?
When fetuses share a placenta. When there’s a connection between blood supplies of 2 fetuses, one fetus may receive majority of blood from placenta while other fetus is starved of blood.
What are the risks for gestational diabetes? (3)
- Previous gestational diabetes
- Previous macrosomic baby (>4.5 kg)
- BMI > 30
- Ethnic origin (black Caribbean, Middle Eastern and South Asian)
- Fhx of diabetes (first-degree relative)
What is the screening test of choice for gestational diabetes? What are the normal results?
Oral glucose tolerance test (OGTT)
Normal results are:
* Fasting: < 5.6 mmol/l
* At 2 hours: < 7.8 mmol/l
Results higher than these values are used to diagnose gestational diabetes.
Mx of pts with gestational diabetes?
- If fasting glucose <7: trial of diet and exercise for 1-2 weeks, followed by metformin, then insulin
- If fasting glucose >7: insulin ± metformin
- If fasting glucose >6 + macrosomia: insulin ± metformin
What are the maternal complications of gestational diabetes?
- Increased risk of hypertension and pre-eclampsia
- Future risk - Increased risk of developing type 2 diabetes and GDM in subsequent pregnancies
What is gestational HTN?
Onset of high BP after 20 wks gestation without presence of proteinuria.
Sx of gestational HTN?
aSx but are detected through elevated BP. Presents after 20 wks gestation w/no proteinuria.
Mx of gestational HTN?
- 1st line - Oral labetalol
- Is not tolerated - alternatives: methyldopa and nifedipine
- Regular urinalysis
What are RF that increase womens likelihood of developing VTE in pregnancy? (3)
> 35 yrs
BMI >30
Parity >3
Smoker
Immobility
Fhx of unprovoked VTE
IVF preggo
What is haemolytic disease of the newborn?
Immunological cdtn when rhesus -ve mother becomes sensitised to rhesus +ve blood cells of her baby while in utero.
Sx of haemolytic disease of the newborn?
- Hydrops fetalis - appears as fetal oedema
- Yellow coloured amniotic fluid - excess bilirubin
- Neonatal jaundice
- Fetal anaemia - skin pallor
- Hepatomegaly or splenomegaly
- Severe oedema
Ix for haemolytic disease of the newborn?
Direct Antiglobulin Test (DAT)
USS - detect foetal oedema
Liver function tests (LFTs)
Tx for gonorrhoea in pregnant or breastfeeding women?
Single dose of intramuscular ceftriaxone or oral azithromycin
What bacteria causes group b strep infx?
Bacterium Streptococcus agalactiae
Sx of group b strep infx in newborn?
Sepsis
Pneumonia
Meningitis
What are the RF that increase the risk of neonatal GBS infx?
- Positive GBS culture in current or previous pregnancy
- Previous birth resulting in neonatal GBS infection
- Pre-term labour
- Prolonged rupture of membranes
- Intrapartum fever >38 degrees Celsius
- Chorioamnionitis
Mx of GBS infx?
Intrapartum abx prophylaxis.
Abx such as penicillin are administered IV during labour and delivery if RF for GBS infx present.
What is the tx for UTI during pregnancy (w/no haematuria)?
1st line: nitrofurantoin for 7 days (avoid at term)
2nd line: if nitro not suitable - amoxicillin/cefelexin for 7 days
What is congenital VZV?
When non-immune women contracts VZV during 1st trimester of preggo. When contracted in early preggo, virus can have teratogenic effects leading to congenital varicella syndrome in newborn.
Sx of congenital varicella syndrome?
Low birth weight
Limb hypoplasia
Skin scarring
Microcephaly
Eye defects
Learning disabilities
Microcephaly is a condition where a baby’s head is much smaller than expected.
Mx of congenital varicella syndrome?
If non-immune preggo comes into contact with infected person - give immunoglobulin as preventative measure
If maternal infx occurs - Acyclovir (within 24hrs of rash onset)
Post delivery - give neonate IV acyclovir + monitor
