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