Master the Boards: Obstetrics

Question 1

The Goodell sign is one of the first signs of pregnancy seen on physical exam. What is it?

Answer 1

Softening of the cervix in first 4 weeks

Question 2

Describe the Chadwick sign?

Answer 2

Blue discoloration of vagina and cervix (6-8 wks GA)

Question 3

Describe chloasma

Answer 3

“mask of pregnancy” seen on face (hyperpigmentation) at 16wks GA

Question 4

What happens to B-hCG levels in each of the first three trimesters?

Answer 4

1: doubles every 48hrs
2: declines
3: slowly increases to a plateau level

Question 5

Physiologic changes in pregnancy - Cardiology

CO:
BP:

Answer 5

CO: Increases (increased HR)
BP: Decreases (lowest at 24-28wks)

Question 6

Physiology changes in pregnancy - Renal

GFR:
BUN:
Creatinine:

Answer 6

GFR: Increases (due to higher plasma volume)
BUN: Decreases
Creatinine: Decreases

Question 7

Physiologic changes in pregnancy - Hematology

Hct:
Coaguability:

Answer 7

HCT: Decreases from dilutional effect
Coaguability: Hypercoaguable, increased fibrinogen, normal PT/PTT/INR

Question 8

What is the most accurate way to measure gestational age in first trimester?

Answer 8

Ultrasound

Question 9

Define Braxton-Hicks contractions

Answer 9

Sporadic contractions occurring in third trimester which do not open the cervix

Question 10

At what GA is the 1 hour glucose load challenge done?

Answer 10

24-28 weeks

Question 11

What drug is used in the medical management of an ectopic pregnancy and what is one major side effect?

Answer 11

Methotrexate

Hepatotoxicity

Question 12

What is the difference between an inevitable and threatened abortion?

Answer 12

Both have intact products of conception and uterine bleeding.

Inevitable: cervix is dilated

Threatened: cervix is closed

Question 13

What medication is used in medical abortion?

Answer 13

Misoprostol: Prostaglandin E1 analog

Question 14

A women presents at 29 weeks gestation with contractions and cervical changes. You determine she is in preterm labor. Her cervix is 4cm dilated. Do you stop the contractions or continue on?

Answer 14

Continue with labor. Dilation of the cervix to 4cm or beyond is an indication to continue with labor.

Question 15

A patient presents in preterm labor at 28 weeks gestation but the fetus is small (

Answer 15

Betamethasone to increase surfactant production. Also give tocolytics to slow uterine contractions so that betamethasone has time to work.

Question 16

What are three tocolytics you may use to slow uterine contractions or stop preterm labor?

Answer 16

Magnesium sulfate
Calcium-channel blockers
Terbutaline (Beta-adrenergic receptor agonist)

Question 17

What is one of the first signs of magnesium sulfate toxicity?
What are more serious side effects you hope to prevent?

Answer 17

Early sign: depression of DTRs

Serious effects: respiratory depression and cardiac arrest

Question 18

When checking for premature rupture of membranes, what does amniotic fluid:

1) do on nitrazine paper
2) look like when dried on a slide

Answer 18

1) Blue

2) Ferning appearance

Question 19

Premature or even prolonged rupture of membranes puts patients at risk for what serious infection?

If the infection is present, what is the management?

Answer 19

Chorioamnionitis
Immediately delivery

(Antibiotic coverage usually includes azithromycin and additional gram positive coverage)

Question 20

A pregnant patient presents with bleeding in her third trimester. Before proceeding with determining if she will need to deliver immediately, what test should be done?

Answer 20

Transabdominal ultrasound. Prior to any digital exam an US needs to rule out placenta previa because digital exam may cause more separation and worsen the bleeding.

Question 21

What is vasa previa?

Answer 21

Subtype of placenta previa where the fetal vessels are actually in close proximity to the cervical os.

Question 22

Should all placenta previas or abruptions be delivered immediately?
In which cases should they be (3)?

Answer 22

No.

Massive hemorrhage
Cervical dilation > 4cm
Fetal distress

When they are delivered, it should be through a C-section

Question 23

Define placenta accreta, increta, and percreta.

Answer 23

Placenta accreta: attaches to superficial uterine wall
Placenta increta: attaches to myometrium
Placenta percreta: invades uterine serosa, bladder wall, or rectum wall

Question 24

Uterine tetany and DIC are complications of what cause of third trimester bleeding?

Answer 24

Placental abruption

Question 25

What are the major risk factors of placental abruption?

Answer 25

Maternal hypertension | Maternal cocaine use and smoking

Question 26

Which patients are at greater risk of uterine rupture, those with previous classic C-sections (vertical incision) or low transverse C-sections?

Answer 26

Those with classic (verticl) incisions

Question 27

What is the management of a uterine rupture?

Answer 27

Immediate laparotomy because the fetus may not be in the uterus but free-floating in the abdomen

Question 28

In hemolytic disease of the newborn, since the BM is not very mature, where are RBCs made?

Answer 28

Liver and spleen (extramedullary production)

Question 29

What BP meds may be used to treat chronic hypertension? What BP med is used in the acute treatment of eclampsia?

Answer 29

Chronic HTN: Methyldopa, Labetalol, Nifedipine Eclampsia: Hydralazine

Question 30

Should you ever tell a pregnant patient to lose weight?

Answer 30

No

Question 31

What are risk factors for fetal macrosomia (>4500g)?

Answer 31

Maternal diabetes Post-term pregnancy Advanced maternal age

Question 32

Above what fetal weight should C-section be performed?

Answer 32

4500g

Question 33

What cause the following decelerations: Early Late Variable

Answer 33

Early: Head compression Late: Uteroplacental insufficiency Variable: Umbilical cord compression

Question 34

After what level of cervical dilation does the latent phase of stage 1 become the active phase?

Answer 34

4 cm

Question 35

Why shouldn't an asthmatic patient receive prostaglandin?

Answer 35

It may provoke bronchospasm

Question 36

Name one cervical ripening agent

Answer 36

Prostaglandin E2

Question 37

Failure of labor to progress is often said to be due to the 3 P's. What are they?

Answer 37

Power: Inadequate uterine contractions Passenger: Fetus too big Passage: Pelvis too small C-section for latter too, oxytocin for inadequate contractions

Question 38

Prior to attempting external cephalic version for suspected breech presentation what should be done?

Answer 38

Ultrasound to confirm position

Question 39

What is the McRobert's maneuver?

Answer 39

Flexion of maternal hips in suspected shoulder dystocia to open pelvic canal wider

Question 40

Uterine atony accounts for 80% of postpartum hemorrhage. What is the mechanism by which atony leads to hemorrhage?

Answer 40

Contractions normally help tamponade bleeding from vessels via compression. No contractions means they are more prone to bleed.

Question 41

What are bimanual compression and massage and oxytocin all used for?

Answer 41

Stopping postpartum hemorrhage

Question 42

What is the Nagel rule?

Answer 42

Estimates day of delivery. Take LMP, subtract 3 months, add 7 days.