Obstetrics 9

  1. What are the lab tests done in third trimester?
    • Oral glucose tolerance test  (typically at 24-28 weeks) 
    • Complete Blood count  -  for anemia 
    • Atypical antibody screen  -  to give RhoGAM 
    • GBS (Group B strep) vaginal culture  -   to give prophylactic penicillin in Labor
  2. What are the differential diagnosis of Third trimester bleeding? [IOM 13]
    • A. Cervical causes - Erosions, polyps, cancer
    • B. Vaginal causes - Varicosities, Lacerations
    • C. Placental causes - Abruptio, placenta previa, vasa previa

    • Abruptio placenta:
    • – 1%  of pregnancy  
    • - painful 

    • Placenta Previa:
    • - 0.5%  of pregnancy
    • -  painless  
    • - typical h/o is wakes up in the middle of night with pool of blood.

    • Vasa previa:
    • - rare  
    • - painless
    • - Fetal blood  [AIIMS 91] 

    • Uterine rupture:
    • - rare
    • - painful
    • - there is loss of station of fetal head
  3. What are the Obstetric causes of DIC ?[UP 95, AIIMS 05]
    • Abruptio placenta - Most common cause 
    • Amniotic  fluid embolism
    • Retained dead fetus
    • Second trimester abortion

    • [Note: Abruptio placenta is the most common cause of
    • - Late pregnancy bleeding
    • - Painful late pregnancy bleeding and
    • - Obstetric DIC]
  4. What are the types of bleeding in Abruptio placenta?
    • Overt bleeding
    • Concealed bleeding 

    Image Upload 1
  5. What is the  position of placenta in Abruptio placenta and placenta previa?
    • Abruptio placenta – Normal position 
    • Placenta previa – abnormal  - low segment
  6. What are the risk factor for Abruptio placenta? [IOM 07]
    • HTN - most important  risk factor. [IOM 09] 
    • Maternal blunt trauma 
    • Cocaine - is a potent vasoconstrictor
    • Folic acid deficiency
    • Prevalence is more with high birth order, previous abruption,  advancing maternal age, malnutrition
  7. What is Couvelaire Uterus?
    Couvelaire uterus (also known as uteroplacental apoplexy)  is a life threatening condition in which loosening of the placenta (abruptio placentae) causes bleeding that penetrates into the uterine myometrium forcing its way into the peritoneal cavity. 

    It is also associated with concealed  accidental hemorrhage. [UP 94]
  8. What is the prevalence of  Placenta previa in 16 weeks and 40 weeks POG?
    • 16 weeks – 20%
    • 40 weeks  -  0.5%
  9. What is trophotropism?
    • Tropho – placenta, tropism – movement.
    • It is the movement of placenta. In early pregnancy, about 20% of cases have placenta, the placenta is close to cervical OS. Over time, the lower part will atrophy and the higher part hypertrophies. This is because the blood supply to the placenta is from the lateral part of uterus ant there is less blood supply to the lower placenta. This process further occurs thus, placenta position is above.  
    • Image Upload 2
  10. What is the pathophysiology of  bleeding in Placenta previa?
    • Avulsion of villi due to stretching of lower uterine segment. As the lower uterine segment stretches with effacement in later part of pregnancy, there is bleeding.  
    • There is no bleeding in early pregnancy in placenta previa because there is no formation of lower uterine segment.
  11. What are the types of Placenta Previa?
    • Type I - Low lying
    • Type II - Marginal, placenta in lower uterine segment, not in OS 
    • Type III - Partial, Placenta partially in Inner OS
    • Type IV - Total central, completely covers the  OS.

    Image Upload 3
  12. What are the risk factor for placenta previa?
    • Previous placenta previa 
    • Multiple pregnancy – the more the number of  placenta, the more the chance 
    • Artificial reproductive techniques  increases  the risk of placenta previa by 5 times.
  13. Why is there increased risk of placenta previa in cases of artificial reproductive techniques?
    In normal pregnancy, the sperm goes up and fertilizes in fallopian tube and the formed morrula  descends  and gets implanted in upper uterine segment. In artificial reproductive techniques, the fertilized zygote is placed in the uterus  descends a little and implants in lower uterine segment, and thus there is more risk. Now a days, the specialists are more careful to  keep the zygote as high as possible to prevent placenta previa.
  14. How do you confirm diagnosis of placenta previa? [IOM 97]
    Sonography provides the simplest, most precise and safest method of placenta localization.
  15. What is the management of placenta previa?
    • Maternal and fetal jeopardy - Emergency CS
    • Preterm stable mother and fetus - Conservative management in hospital. 
    • Marginal placenta >2cm form OS - Vaginal delivery 
    • Term stable mother and fetus - Scheduled CS. 

    Per vaginal examination is contraindicated in placenta previa. [IOM 09]
  16. What is the expectant management of Placenta previa? [AI 11]
    • Rest. Absolute bed rest for upto 72 hours after bleeding stops. 
    • Careful monitoring - Clinical, laboratory, USG every 2-3 weeks. 
    • Blood tranfusion and hematinics. Maintain Hb at least 10 g/dl and hematocrit of 30%. 
    • Antenatal steroid for fetal maturity between 24-34 weeks of gestation. There is no evidence to support the use of antenatal steroids after 34 weeks of gestation. 
    • Anti D immunoglobulins to all Rh negative women. 
    • Use of tocolytics (controversial). 
    • Cervical encirclage not currently recommended.
  17. What is placenta accreta?
    If placenta is present over a previous uterine scar, the villi may invade beyond Nitabuch Layer resulting in Placenta Accreta.
  18. What is the treatment of choice for placenta accreta? [UP 01]
    Hysterectomy - but in patients desiring to have a child, conservative attitude may be taken.
  19. What is Nitabuch layer?
    • It is the layer of fibrinoid degeneration which separates the superficial layer of decidua basalis from the deeper layer of deciduas basalis.
    • The normal placenta does not go beyond the Nitabuchs layer.

    Image Upload 4
  20. What is placenta accreta, placenta  increta and placenta percreta?
    • Accreta – villi invade deep basalis layer 
    • Increta – villi invades partial myometrium 
    • Percreta  - vlli invades to serosa/bladder. 

    • [@Pacental attachment:
    • Accreta- Attaches
    • Increta - Invades
    • Percreta - Penetrates]

    Image Upload 5
  21. Risk factors for placenta accreta include all of the following except [AI 08]

    D) Previous placenta previa

    • Risk factors of placenta accreta are 
    • - Placenta previa (present pregnancy) 
    • - Previous C/S
    • - Previous curettage 
    • - Previous myomectomy 
    • - Multiparity 
    • - Advanced maternal age (≥35 years) 

    Presence of placenta previa in the present pregnancy forms the most important risk factor. Placenta accreta should be suspected in all women with placenta previa.
  22. 23 yr G1P0 at 35 wks POG with a fetus in transverse lie. Which of the following conditions should be suspected?

    D) Placenta  previa
  23. 23 yr G1P0 at 35 wks POG with a fetus in  breech lie. Which of the following conditions should be suspected?  

    D) Uterine septum

    • The fetus is going to have its feet where the space is more. Normally, more space is in the fundus of uterus and thus, the foot is present in the fundus of uterus normally.
    • If the fundus  of uterus is limited either by septum or uterine anamaly,  the fetus is going to have its feet down and is going to be in  breech presentation.
  24. A 21 yr G3P1Ab1, 34 weeks POG, with painful 3rd trimester Bleeding. She has past h/o of placenta previa. What is the most probable diagnosis?
    Abruptio placenta

    Though she has higher risk of placenta previa, but now the bleeding is painful, so abruption-placenta.
  25. What is vasa previa?  What is the management? Complication?
    • The  blood vessel connecting the main placental disc and the accessory placental disc,  if overlies the cervix, it is called as vasa previa.
    • These vessels are not protected by umbilical cord and thus more chance of bleeding.
    • The bleeding is from fetal blood vessles.  The bleeding is painless and the placenta location is normal.
    • The treatment  is immediate cesarean.
    • The complication is fetal hypovolemia.    
    • Image Upload 6
  26. What is the diagnostic triad of Vasa previa?
    • 1. Rupture of Membrane  followed by
    • 2. Vaginal bleeding followed by 
    • 3. Fetal Bradycardia
  27. What are the risk factors of Vasa previa?
    • Velamentous cord 
    • Accessory placental lobe 
    • Multiple gestation
  28. What  is Velamentous insertion of Umbilical cord?
    • Normally the umbilical cord origins  from  the disc of placenta,
    • In velamentous cord insertion,  the cord takes its origin  on the membranes

    Image Upload 7

    Image Upload 8
  29. What is the most common cause of uterine rupture?
    Previous classical uterine incision
  30. What is the  diagnostic triad of  Ruptured Uterus?
    • 1. Painful bleeding 
    • 2. Loss of fetal heart rate 
    • 3. Loss of station of fetal head
Card Set
Obstetrics 9