Labor and Delivery Practice Questions

Q: What is the definition of secondary arrest of labor?

None of the above.. The definition of **Secondary Arrest of Dilatation** refers to a situation in the **active phase** of labor where cervical dilatation ceases for a period of **2 hours or more**, regardless of parity. ### Why Option D is Correct The correct definition of secondary arrest is the cessation of cervical dilatation for $\geq$ 2 hours during the active phase. Option A is incorrect because it specifies "nullipara," whereas the 2-hour rule applies to both nulliparous and multiparous women. Since none of the provided options accurately reflect the standard Friedman’s or WHO criteria for secondary arrest, "None of the above" is the correct choice. ### Analysis of Incorrect Options * **Option A:** Incorrect because secondary arrest is defined by the duration of the arrest (2 hours), not the parity of the patient. * **Option B:** This describes a **Prolonged Latent Phase** in a multipara. (Latent phase $>20$ hours in nullipara; $>14$ hours in multipara). * **Option C:** This describes **Arrest of Descent**. Arrest of descent is diagnosed when the fetal station does not change for 1 hour or more during the second stage of labor. ### NEET-PG High-Yield Pearls * **Active Phase:** Starts at 4 cm (Friedman) or 6 cm (ACOG/modern guidelines) cervical dilatation. * **Protraction Disorder:** Dilatation is slow ($<1.2$ cm/hr in nullipara; $<1.5$ cm/hr in multipara). * **Arrest Disorder:** No change in dilatation for $\geq 2$ hours (Secondary Arrest) or no descent for $\geq 1$ hour. * **Most Common Cause:** Cephalopelvic Disproportion (CPD) is the most frequent cause of secondary arrest. Always rule out CPD before starting oxytocin.

Q: What is the average pressure of uterine contractions during the first stage of labor?

30 mm Hg. In labor, uterine activity is measured by the intensity and frequency of contractions. The correct answer is **30 mm Hg** because it represents the average peak intrauterine pressure during the first stage of labor. ### **Detailed Explanation** 1. **Why 30 mm Hg is correct:** During the first stage of labor, the intensity of contractions typically ranges from **30 to 50 mm Hg**. This pressure is sufficient to cause progressive cervical effacement and dilation. It is important to note that the "critical threshold" of pressure required to cause cervical change is approximately **15–20 mm Hg**. 2. **Why other options are incorrect:** * **100 mm Hg (Option A):** This is excessively high. Pressures reaching 100 mm Hg are typically only seen during the **second stage of labor** (expulsive phase), where maternal bearing-down efforts (Valsalva) are added to the uterine contraction. * **15 mm Hg (Option B):** This represents the lower limit of a contraction's intensity. While it may be felt by the patient, it is usually insufficient to produce rapid cervical dilation. * **20 mm Hg (Option C):** This is the threshold at which the uterus feels "hard" on abdominal palpation, but it is below the average peak pressure of an established first-stage labor contraction. ### **NEET-PG High-Yield Pearls** * **Tonus:** The resting intrauterine pressure between contractions is **8–12 mm Hg**. If it exceeds 12 mm Hg, it is termed hypertonicity. * **Montevideo Units (MVU):** Calculated by multiplying the frequency of contractions (in 10 mins) by their average intensity. **200–250 MVUs** are considered adequate for labor progression. * **Pain Threshold:** A patient usually begins to perceive pain when the contraction pressure exceeds **15 mm Hg**. * **Triple Descending Gradient:** Normal labor contractions originate at the fundus (pacemaker) and propagate downwards; the intensity is greatest at the fundus and least in the lower uterine segment.

Q: Aboition is defined as the expulsion of a fetus weighing less than how many grams?

500. **Explanation:** **Abortion** is defined as the termination of pregnancy before the period of viability. According to the **World Health Organization (WHO)** and the **National Health Mission (NHM)** guidelines, the criteria for abortion are based on two parameters: 1. **Gestational Age:** Less than **20 weeks** (in some countries, 24 weeks is used, but 20 weeks remains the standard for most examinations). 2. **Fetal Weight:** Less than **500 grams**. **Option A (500g)** is correct because it represents the threshold of viability. A fetus weighing less than 500g is generally considered incapable of independent extrauterine survival given current medical technology. **Why other options are incorrect:** * **Option B (800g) and C (900g):** These values do not correspond to any standard legal or clinical definitions of viability or abortion in international classifications. * **Option D (1000g):** While 1000g (or 28 weeks) was historically used as the limit of viability in India, modern guidelines have shifted this down to 500g/20 weeks to align with international standards. **High-Yield Clinical Pearls for NEET-PG:** * **MTP Act (India):** The Medical Termination of Pregnancy (Amendment) Act 2021 allows for the termination of pregnancy up to **24 weeks** for specific categories of women, but the biological definition of abortion remains linked to the 500g/20-week threshold. * **Most Common Cause:** The most common cause of spontaneous abortion in the first trimester is **fetal chromosomal anomalies** (Autosomal Trisomy being the most frequent). * **Stillbirth vs. Abortion:** If the fetus is born dead after 20 weeks or weighing >500g, it is classified as a **Stillbirth**, not an abortion.

Q: HIV transmission to the fetus is maximum during which period?

Vaginal delivery. **Explanation:** The risk of Mother-to-Child Transmission (MTCT) of HIV occurs at three stages: antenatal (in utero), intranatal (during labor/delivery), and postnatal (breastfeeding). **Why Vaginal Delivery is the Correct Answer:** The majority of HIV transmissions (**60–75%**) occur during the **intranatal period** (labor and delivery). This is primarily due to: 1. **Direct Contact:** The fetus is exposed to infected maternal blood and cervicovaginal secretions in the birth canal. 2. **Micro-transfusions:** During uterine contractions, small amounts of maternal blood are forced across the placenta into the fetal circulation. 3. **Ascending Infection:** Rupture of membranes allows the virus to ascend from the vagina into the amniotic cavity. **Analysis of Incorrect Options:** * **A & B (1st and 2nd Trimester):** Transmission is rare in early pregnancy (approx. 5–10%) because the placental barrier is relatively intact and the viral load in the amniotic fluid is low. * **C (3rd Trimester):** While the risk increases as the placenta ages and thins, it still accounts for only a minority of cases compared to the massive exposure during active labor. **High-Yield Clinical Pearls for NEET-PG:** * **Most important predictor of transmission:** Maternal plasma viral load. * **Zidovudine (AZT):** The first drug proven to reduce MTCT. * **Mode of Delivery:** Elective Cesarean Section (at 38 weeks, before labor/ROM) is recommended if the viral load is **>1,000 copies/mL**. If <50 copies/mL, vaginal delivery is safe. * **Breastfeeding:** In India, exclusive breastfeeding is recommended for 6 months if replacement feeding is not "Acceptable, Feasible, Affordable, Sustainable, and Safe" (AFASS). * **Prophylaxis:** Nevirapine is given to the infant for 6–12 weeks depending on maternal ART duration.

Question 1

What is the definition of secondary arrest of labor?

Accepted Answer

None of the above.

Answer

Secondary arrest of dilatation by more than 2 hours in a nullipara.

Answer

Latent phase lasting more than 14 hours in a multipara.

Answer

Arrest in descent for more than 1 hour in a nullipara.

Question 2

What is the average pressure of uterine contractions during the first stage of labor?

Accepted Answer

30 mm Hg

Answer

100 mm Hg

Answer

15 mm Hg

Answer

20 mm Hg

Question 3

Which of the following is a contraindication to External Cephalic Version?

Accepted Answer

Hydramnios

Answer

Contracted pelvis

Answer

Antepartum hemorrhage

Answer

Multiple pregnancy

Question 4

Aboition is defined as the expulsion of a fetus weighing less than how many grams?

Accepted Answer

500

Answer

800

Answer

900

Answer

1000

Question 5

Which of the following statements regarding twin delivery is true?

Accepted Answer

The second twin has a higher chance of developing polycythemia.

Answer

The first twin has a higher chance of asphyxia.

Answer

The second twin has a higher chance of developing hyaline membrane disease.

Answer

There is increased mortality in the first twin.

Question 6

Which of the following is NOT a sign of placental separation?

Accepted Answer

Uterus becomes globular

Answer

Uterus rises in the abdomen

Answer

Lengthening of the umbilical cord

Answer

Fresh gush of blood from the vagina

Question 7

HIV transmission to the fetus is maximum during which period?

Accepted Answer

Vaginal delivery

Answer

1st trimester

Answer

2nd trimester

Answer

3rd trimester

Question 8

Complete or incomplete uterine inversion depends on whether the fundus has passed through which level?

Accepted Answer

The complete uterus outside the introitus

Answer

Minimally below the normal level

Answer

The level of the vagina

Answer

The level of the cervix

Question 9

Fetal bradycardia is defined as:

Accepted Answer

Less than 120 beats per minute for a period of 15 minutes of continuous monitoring

Answer

Less than 100 beats per minute

Answer

Between 100 and 200 beats per minute

Answer

Less than 120 beats per minute

Question 10

When should a perineal tear be repaired?

Accepted Answer

Immediately

Answer

24 hours later

Answer

48 hours later

Answer

36 hours later

Labor and Delivery — MCQs

Labor and Delivery — MCQs

On this page

Practice by Chapter

Want unlimited practice?