Labor and Delivery — MCQs

Labor and Delivery Indian Medical PG Practice Questions and MCQs

Question 661: Which among the following is the smallest diameter of the pelvis in the midplane?

A. Interspinous diameter (Correct Answer)
B. True conjugate
C. Diagonal conjugate
D. Intertuberous diameter

Explanation: The **interspinous diameter** is the smallest diameter of the entire pelvis. It measures the distance between the two ischial spines in the mid-pelvis (plane of least pelvic dimensions). ### Why the Correct Answer is Right: * **Interspinous Diameter:** Measuring approximately **10 cm**, it represents the narrowest point through which the fetal head must pass during labor. It marks the "plane of least pelvic dimensions." If this diameter is <9 cm, it indicates mid-pelvic contraction, which can lead to transverse arrest of the fetal head. ### Why the Other Options are Wrong: * **True Conjugate (11 cm):** This is the anteroposterior diameter of the pelvic **inlet** (from the sacral promontory to the upper border of the symphysis pubis). While important, it is larger than the interspinous diameter. * **Diagonal Conjugate (12.5 cm):** This is the only diameter of the inlet that can be measured clinically via vaginal examination. It is significantly larger than the interspinous diameter. * **Intertuberous Diameter (11 cm):** This is the transverse diameter of the pelvic **outlet**, measured between the inner borders of the ischial tuberosities. ### NEET-PG High-Yield Pearls: 1. **Smallest Diameter Overall:** Interspinous diameter (10 cm). 2. **Obstetric Conjugate:** The shortest AP diameter of the inlet (approx. 10.5 cm), calculated as *Diagonal Conjugate minus 1.5 to 2 cm*. 3. **Mid-pelvic Arrest:** Usually occurs at the level of the ischial spines (station 0). 4. **Clinical Assessment:** If the ischial spines are prominent on per-vaginal exam, it suggests a narrow interspinous diameter and a possible android pelvis.

Question 662: A per vaginum (PV) examination is contraindicated in which of the following conditions?

A. Placenta previa (Correct Answer)
B. Cord prolapse
C. Ruptured membranes
D. Cephalopelvic disproportion (CPD)

Explanation: **Explanation:** The correct answer is **Placenta previa**. **1. Why Placenta Previa is the Correct Answer:** In placenta previa, the placenta is implanted in the lower uterine segment, covering or lying near the internal os. Performing a digital per vaginum (PV) examination can cause mechanical trauma to the highly vascular placental tissue or trigger the separation of the placenta from the uterine wall. This can lead to **sudden, torrential, and life-threatening maternal hemorrhage**. Therefore, a PV exam is strictly contraindicated until placenta previa is ruled out by ultrasound (the "Double Setup" exam in the OT is the only exception, though rarely performed now). **2. Why Other Options are Incorrect:** * **Cord Prolapse:** A PV examination is essential here to confirm the diagnosis (feeling a pulsating cord) and to manually displace the presenting part upward to relieve pressure on the cord until an emergency cesarean section is performed. * **Ruptured Membranes:** While frequent exams should be avoided to minimize the risk of chorioamnionitis, a sterile speculum or PV exam is often necessary to confirm the diagnosis, assess cervical status, or check for cord prolapse. * **Cephalopelvic Disproportion (CPD):** A PV exam (specifically clinical pelvimetry) is required to assess the pelvic diameters and the degree of molding or caput formation to diagnose CPD. **3. High-Yield Clinical Pearls for NEET-PG:** * **Golden Rule:** "Never perform a PV exam in a case of Antepartum Hemorrhage (APH) until placenta previa is ruled out by USG." * **Investigation of Choice:** Transvaginal Sonography (TVS) is the gold standard for diagnosing placenta previa (it is safer and more accurate than transabdominal). * **Stallworthy's Sign:** A drop in fetal heart rate when the head is pressed into the pelvis, suggestive of posterior placenta previa.

Question 663: Which of the following can cause a face presentation during labor?

A. Anencephaly (Correct Answer)
B. Contracted pelvis
C. Placenta previa
D. Thyroid swelling

Explanation: **Explanation:** Face presentation occurs when the fetal head is in a state of **complete extension**, causing the mentum (chin) to be the presenting part. **Why Anencephaly is the Correct Answer:** Anencephaly is the most common fetal cause of face presentation. In these fetuses, the absence of the cranial vault (calvarium) and the rudimentary development of the brain result in a lack of the normal fetal "attitude" of flexion. The absence of the vertex means there is no bony structure to engage normally, and the spinal muscles often pull the head backward, leading to a forced extension. **Analysis of Incorrect Options:** * **Contracted Pelvis:** While a contracted pelvis (specifically a flat pelvis) can cause malpresentations, it more commonly leads to **deflexed vertex** or **brow presentations**. If the head cannot engage, it may extend, but it is a less direct cause compared to the structural absence in anencephaly. * **Placenta Previa:** This typically results in **high floating heads** or **transverse/oblique lies** because the placenta occupies the lower uterine segment, preventing the head from entering the pelvis altogether. * **Thyroid Swelling:** While a massive fetal neck tumor (like a cystic hygroma or goiter) can mechanically prevent flexion and cause extension, a simple "thyroid swelling" is a less common and less specific cause compared to the classic association with anencephaly. **NEET-PG High-Yield Pearls:** * **Most common cause:** Multiparity (due to lax abdominal muscles). * **Most common fetal cause:** Anencephaly. * **Denominator:** Mentum (Chin). * **Engaging diameter:** Submentobregmatic (9.5 cm). * **Management:** Mentum Anterior (MA) can deliver vaginally; **Mentum Posterior (MP) cannot deliver vaginally** (the "long internal rotation" of 3/8th of a circle must occur to convert MP to MA).

Question 664: A woman at 8 months of pregnancy complains of abdominal pain and slight vaginal bleeding. On examination, the uterine size is larger than expected for dates, and fetal heart sounds are absent. What is the most likely diagnosis?

A. Hydramnios
B. Concealed hemorrhage (Correct Answer)
C. Active labor
D. Uterine rupture

Explanation: This question describes a classic presentation of **Abruptio Placentae**, specifically the **concealed variety**. ### **Explanation of the Correct Answer** In **concealed accidental hemorrhage**, blood collects behind the placenta (retroplacental clot) and does not escape through the cervix. This leads to several key clinical findings: * **Uterine size > Dates:** The accumulation of blood within the uterine cavity increases the fundal height beyond what is expected for the gestational age. * **Abdominal Pain:** The uterus becomes tense, tender, and "board-like" due to the irritating effect of the retroplacental hematoma. * **Absent Fetal Heart Sounds (FHS):** Severe placental separation leads to acute fetal hypoxia and intrauterine fetal death. * **Slight Bleeding:** Even in "concealed" cases, a small amount of dark vaginal bleeding (revealed component) is often present. ### **Why Other Options are Incorrect** * **A. Hydramnios:** While this causes a uterus larger than dates, it is usually painless and associated with easily audible (though muffled) FHS. It does not cause vaginal bleeding. * **C. Active Labor:** Labor presents with rhythmic contractions and cervical changes. It does not explain a uterus larger than dates or the sudden absence of FHS. * **D. Uterine Rupture:** This typically occurs during labor (often in a scarred uterus). On examination, fetal parts are easily palpable under the skin, and the uterus usually becomes **smaller** or recedes as the fetus is extruded into the peritoneal cavity. ### **NEET-PG High-Yield Pearls** * **Couvelaire Uterus:** A complication of concealed abruption where blood infiltrates the myometrium, giving it a port-wine appearance. * **Consumptive Coagulopathy (DIC):** More common in the concealed variety due to the release of thromboplastin into the maternal circulation. * **Classic Triad of Abruption:** Abdominal pain, uterine tenderness/hypertonicity, and vaginal bleeding.

Question 665: Which of the following is an example of abnormal fetal attitude?

A. Breech presentation
B. Face presentation (Correct Answer)
C. Transverse position
D. Occiput posterior

Explanation: ***Face presentation*** - Represents **abnormal fetal attitude** where the fetal head is hyperextended with the **face presenting** at the pelvic inlet instead of the vertex. - **Fetal attitude** refers to the degree of flexion of the fetal head and limbs; face presentation shows **hyperextension** of the neck, which is abnormal. *Breech presentation* - This describes **fetal presentation** (the part of fetus presenting at pelvic inlet), not fetal attitude. - In breech, the **buttocks or feet** present first, but the fetal attitude (degree of flexion) can still be normal. *Transverse position* - This refers to **fetal lie** (relationship of fetal long axis to maternal long axis), not fetal attitude. - In transverse lie, the fetus lies **perpendicular** to the maternal spine with **shoulder presenting** first. *Occiput posterior* - This describes **fetal position** (relationship of fetal presenting part to maternal pelvis), not fetal attitude. - **OP position** means the fetal occiput faces the **maternal sacrum**, but head flexion (attitude) remains normal.

Question 666: Which of the following is true regarding vasa previa, except?

A. Incidence is 1:1500
B. Mortality rate is 20% with undiagnosed cases (Correct Answer)
C. Associated with low-lying placenta
D. Cesarean section is indicated

Explanation: **Explanation:** **Vasa Previa** is a rare but life-threatening obstetric emergency where fetal vessels run through the fetal membranes, unprotected by placental tissue or the umbilical cord, across the internal os. **Why Option B is the correct answer (The "Except" statement):** The mortality rate for **undiagnosed** vasa previa is significantly higher than 20%, often cited between **50% and 95%**. Because the vessels are fetal in origin, rupture of membranes (spontaneous or artificial) leads to rapid fetal exsanguination. The 20% figure is inaccurate; conversely, when diagnosed prenatally, the survival rate increases to over 95%. **Analysis of other options:** * **Option A:** The incidence is approximately **1 in 2,500 to 1 in 5,000** pregnancies, though some studies suggest it may be as high as 1:1500 in high-risk populations (like IVF). It is considered a rare condition. * **Option C:** Risk factors include a **low-lying placenta**, placenta previa, velamentous cord insertion, succenturiate placental lobes, and pregnancies resulting from IVF. * **Option D:** Once diagnosed, a **planned Cesarean section** is mandatory (usually at 34–36 weeks) to avoid labor and the risk of membrane rupture, which would be fatal for the fetus. **NEET-PG High-Yield Pearls:** * **Classic Triad:** Rupture of membranes + Painless vaginal bleeding + Fetal bradycardia/distress. * **Diagnostic Test:** **Apt test** or **Ogita test** can differentiate fetal hemoglobin from maternal blood. * **Gold Standard Diagnosis:** Antenatal **Color Doppler Ultrasound** (showing pulsating vessels over the internal os). * **Management:** If diagnosed prenatally, admit by 30–32 weeks for monitoring and deliver via elective LSCS before labor begins.

Question 667: In a patient with a history of a previous stillbirth, what is the optimum time for delivery?

A. 37 weeks
B. 38 weeks
C. 39 weeks (Correct Answer)
D. 40 weeks

Explanation: **Explanation:** The management of a pregnancy following a previous unexplained stillbirth requires a delicate balance between the risks of recurrent stillbirth and the risks associated with iatrogenic prematurity. **Why 39 weeks is correct:** Current clinical guidelines (including ACOG and RCOG) recommend delivery at **39 weeks 0 days to 39 weeks 6 days** for women with a history of a prior unexplained stillbirth, provided the current pregnancy is otherwise uncomplicated. Delivering at 39 weeks significantly reduces the risk of late-term stillbirth while ensuring the fetus has reached full maturity, thereby minimizing the risks of Respiratory Distress Syndrome (RDS) and NICU admissions associated with early-term delivery. **Analysis of Incorrect Options:** * **37 & 38 weeks (A & B):** Delivery before 39 weeks is considered "early-term." While it further reduces the risk of stillbirth, it is associated with higher rates of neonatal morbidity (respiratory issues, feeding difficulties, and jaundice). These are generally reserved for cases with co-existing complications like preeclampsia or FGR. * **40 weeks (D):** Waiting until the due date or beyond increases the risk of placental insufficiency and stillbirth, which is statistically higher in patients with a prior history of intrauterine fetal death (IUFD). **Clinical Pearls for NEET-PG:** * **Monitoring:** In patients with prior stillbirth, antenatal surveillance (NST/BPP) usually commences at **32–36 weeks**. * **The "Rule of 39":** For most elective inductions or repeat C-sections without maternal/fetal complications, 39 weeks is the "magic number" to ensure optimal neonatal outcomes. * **Recurrence Risk:** The risk of stillbirth in a subsequent pregnancy is approximately 2–5 times higher than in the general population.

Question 668: What are the causes of face presentation during labor?

A. Anencephaly
B. Prematurity
C. Contracted pelvis
D. All of the above (Correct Answer)

Explanation: **Explanation:** Face presentation occurs when the fetal head is **hyperextended** such that the occiput is in contact with the fetal back, and the face (mentum) becomes the presenting part. This occurs due to factors that either prevent flexion or actively encourage extension of the fetal head. **Why "All of the above" is correct:** * **Anencephaly (Option A):** This is the most common fetal cause. Due to the absence of the cranial vault and a poorly developed brain, the head naturally falls into extension. * **Prematurity (Option B):** In preterm labor, the small size of the fetal head relative to the amniotic fluid volume allows for increased mobility and unstable lie/presentation, often resulting in extension before the head engages. * **Contracted Pelvis (Option C):** This is a common maternal cause. In a flat (platypelloid) pelvis, the biparietal diameter may get caught at the pelvic brim, causing the head to tilt and extend to allow smaller diameters to engage. **Clinical Pearls for NEET-PG:** 1. **Incidence:** Approximately 1 in 500 deliveries. 2. **Denominator:** The **Mentum** (chin). 3. **Mechanism of Labor:** Only **Mentum Anterior (MA)** positions can deliver vaginally. **Mentum Posterior (MP)** cannot be delivered vaginally because the short fetal neck cannot navigate the long maternal sacrum (the "sternum meets the symphysis" deadlock). 4. **Management:** If Mentum Posterior persists, a **Cesarean Section** is mandatory. Internal podalic version and manual rotation are contraindicated in modern practice. 5. **Associated Sign:** On abdominal palpation, a deep groove may be felt between the occiput and the fetal back (the "S-shaped" curve).

Question 669: What is the period from full dilatation of the cervix to the complete birth of the baby?

A. 1st stage
B. 2nd stage (Correct Answer)
C. 3rd stage
D. 4th stage

Explanation: The labor process is clinically divided into four distinct stages based on physiological milestones. Understanding these transitions is crucial for NEET-PG, as management protocols change with each stage. ### **Explanation of the Correct Answer** **Option B (2nd stage)** is correct. The second stage of labor begins when the **cervix is fully dilated (10 cm)** and ends with the **complete expulsion of the fetus** from the birth canal. This stage is characterized by the maternal "bearing down" reflex (Ferguson reflex) and the descent of the fetal presenting part. ### **Analysis of Incorrect Options** * **Option A (1st stage):** This is the stage of cervical effacement and dilatation. It starts with the onset of true labor pains and ends at full dilatation (10 cm). It is further divided into Latent and Active phases. * **Option C (3rd stage):** This stage begins immediately after the birth of the baby and ends with the **expulsion of the placenta and membranes**. * **Option D (4th stage):** This is the "stage of observation," lasting at least one hour after placental delivery. It is critical for monitoring postpartum hemorrhage (PPH) and ensuring uterine contraction. ### **High-Yield Clinical Pearls for NEET-PG** * **Duration of 2nd Stage:** In a primigravida, it typically lasts **2 hours** (3 hours with epidural); in a multigravida, it lasts **1 hour** (2 hours with epidural). * **Phases of 2nd Stage:** It is divided into the **Propulsive phase** (from full dilatation to the head reaching the pelvic floor) and the **Expulsive phase** (maternal bearing down efforts leading to delivery). * **Active Management:** The 2nd stage is when the "Ritgen maneuver" is performed to support the perineum and control the delivery of the head.

Question 670: A primigravida presents at 36 weeks of gestation with preterm premature rupture of membranes or leaking per vaginum. What is the appropriate management?

A. External Cephalic Version (ECV)
B. Lower Segment Caesarean Section (LSCS) (Correct Answer)
C. Induction of labor
D. Internal Podalic Version (IPV)

Explanation: ### Explanation **Correct Option: B. Lower Segment Caesarean Section (LSCS)** In a **primigravida** at 36 weeks with Preterm Premature Rupture of Membranes (PPROM), the management depends on the fetal presentation and cervical status. While induction is often considered in multiparous women or those with a favorable cervix, the standard teaching for a primigravida at near-term (34–36 weeks) with PPROM—especially if the cervix is unfavorable or there are signs of fetal distress/malpresentation—is to proceed with **LSCS** to minimize the risk of ascending infection (chorioamnionitis) and cord prolapse. In the context of this specific MCQ, LSCS is prioritized as the definitive management to ensure a safe delivery. **Why other options are incorrect:** * **A. External Cephalic Version (ECV):** This is absolutely contraindicated in cases of ruptured membranes (PPROM) because the lack of amniotic fluid makes the procedure technically impossible and increases the risk of placental abruption or cord entanglement. * **C. Induction of Labor:** While induction is an option for PPROM at 36 weeks, it is generally preferred in multigravidas. In a primigravida, the high failure rate of induction with an unfavorable cervix often leads to prolonged labor and increased infection risk. * **D. Internal Podalic Version (IPV):** This is only performed for the delivery of the second twin in a twin pregnancy. It is never used for a singleton pregnancy at 36 weeks. **Clinical Pearls for NEET-PG:** * **Definition of PPROM:** Rupture of membranes before 37 weeks and before the onset of labor. * **Management Cut-off:** If PPROM occurs at **>34 weeks**, the consensus is to proceed with delivery (active management) rather than expectant management. * **Diagnosis:** The "Gold Standard" is the visualization of fluid pooling in the posterior vaginal fornix on sterile speculum exam. * **Nitrazine Test:** Turns blue (alkaline pH of 7.0–7.5) in the presence of amniotic fluid. * **Fern Test:** Microscopic crystallization of salts in amniotic fluid; highly specific for ROM.

Practice by Chapter

Physiology of Labor

Practice Questions

Stages of Labor and Normal Progression

Practice Questions

Fetal Monitoring Techniques

Practice Questions

Pain Management in Labor

Practice Questions

Induction and Augmentation of Labor

Practice Questions

Operative Delivery (Forceps and Vacuum)

Practice Questions

Cesarean Section: Indications and Techniques

Practice Questions

Dystocia and Abnormal Labor Patterns

Practice Questions

Obstetric Emergencies

Practice Questions

Postpartum Hemorrhage Management

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free