Complete Guide to NEET PG OBG High-Yield Topics

Version 1.0 — Published April 2026

Obstetrics and Gynecology is a subject where clinical scenarios dominate. NBE rarely tests isolated facts — instead, you get a pregnant woman at a specific gestational age with specific symptoms, and you must choose the next step. A 32-week primigravida with painless bleeding is placenta previa until proven otherwise. A postpartum woman with a boggy uterus and continuous bleeding is uterine atony. The gestational age, the symptom pattern, and the clinical context together determine the answer.

This guide covers the eight highest-yield OBG areas with the clinical detail NBE tests. Each section gives you the diagnostic criteria, the management protocols, and the discriminators that separate the correct answer from the close-but-wrong options. Pair it with the Obstetrics and Gynecology subject hub for daily MCQ practice.

Normal labor: stages, partograph, and cardinal movements

Normal labor is the physiological process of delivery at term (37-42 weeks) through the birth canal. Understanding the stages, the partograph, and the cardinal movements is foundational — these concepts underpin all obstetric management questions.

Stages of labor

The active phase cervical dilatation rate is the most tested parameter. In a primigravida, dilatation should progress at least 1 cm/hour. Slower progress crosses the alert line on the partograph and warrants assessment. If progress crosses the action line (4 hours to the right of the alert line), intervention is indicated.

The partograph

The WHO partograph is a graphical record of labor progress. NBE tests partograph interpretation in clinical vignettes.

• Alert line: starts at 4 cm dilatation and advances at 1 cm/hour. Cervical dilatation plotted to the left of this line indicates normal progress.
• Action line: 4 hours to the right of the alert line. Dilatation crossing this line indicates prolonged labor requiring intervention (augmentation, cesarean section, or referral).
• Other parameters monitored: fetal heart rate (normal: 110-160 bpm), contractions (frequency and duration), descent of head, maternal vital signs, urine output.

Cardinal movements of labor

The seven cardinal movements describe how the fetal head navigates the birth canal:

1. Engagement — biparietal diameter passes the pelvic inlet
2. Descent — continuous throughout labor, driven by uterine contractions and maternal pushing
3. Flexion — chin touches chest, presenting the smallest diameter (suboccipitobregmatic, 9.5 cm)
4. Internal rotation — occiput rotates from transverse to anterior (OA position), aligning with the AP diameter of the pelvic outlet
5. Extension — head extends as it emerges under the pubic symphysis
6. External rotation (restitution) — head rotates back to its original position relative to the shoulders
7. Expulsion — delivery of the anterior then posterior shoulder

The suboccipitobregmatic diameter (9.5 cm) is the presenting diameter in a well-flexed vertex presentation (normal). In brow presentation, the presenting diameter is mentovertical (13.5 cm) — the largest diameter, making vaginal delivery impossible. In face presentation, the presenting diameter is submentobregmatic (9.5 cm), and vaginal delivery is possible only in mento-anterior position. These diameter-presentation associations are frequently tested.

Bishop score

The Bishop score assesses cervical readiness for induction of labor. Five parameters are scored: dilatation, effacement, station, consistency, and position of cervix.

• Score of 8 or more: favorable cervix, induction likely to succeed
• Score less than 6: unfavorable cervix, cervical ripening required (prostaglandin E2 gel or misoprostol)

High-risk pregnancy: preeclampsia, GDM, and Rh isoimmunization

High-risk pregnancy questions account for 5-7 marks in every NEET PG paper. Preeclampsia/eclampsia is the single most tested obstetric topic. NBE presents clinical scenarios and asks for diagnosis, management, or the next investigation.

Preeclampsia and eclampsia

Preeclampsia is a pregnancy-specific syndrome defined by new-onset hypertension (BP >=140/90 mmHg after 20 weeks of gestation) with proteinuria (>=300 mg/24 hours) or other end-organ dysfunction. It complicates 5-8% of pregnancies worldwide.

Severe preeclampsia criteria (any one):

• BP >=160/110 mmHg on two occasions 4 hours apart
• Thrombocytopenia (<100,000/microL)
• Elevated liver transaminases (>2x normal)
• Renal insufficiency (creatinine >1.1 mg/dL or doubling)
• Pulmonary edema
• Cerebral or visual disturbances
• HELLP syndrome: Hemolysis, Elevated Liver enzymes, Low Platelets — a severe variant

Eclampsia is preeclampsia with generalized tonic-clonic seizures not attributable to other causes.

Management of eclampsia — magnesium sulfate (MgSO4):

The Pritchard regimen is the standard in India and the most tested protocol:

• Loading dose: 4 g IV over 15-20 minutes + 5 g IM in each buttock (total 14 g)
• Maintenance: 5 g IM every 4 hours in alternate buttocks for 24 hours after the last seizure
• Therapeutic range: 4-7 mEq/L
• Before each dose, check: patellar reflex (must be present), respiratory rate (must be >16/min), urine output (must be >25 mL/hour)

Toxicity signs in ascending order:

1. Loss of patellar reflex (8-10 mEq/L) — first sign
2. Respiratory depression (>12 mEq/L)
3. Cardiac arrest (>15 mEq/L)

Antidote: 10% calcium gluconate, 10 mL IV over 3 minutes. This sequence (therapeutic range, toxicity signs, antidote) appears in NEET PG almost every year.

Definitive treatment of preeclampsia is delivery. The decision depends on gestational age and severity. Severe preeclampsia at >=34 weeks: deliver after stabilization. Mild preeclampsia: can be managed expectantly until 37 weeks.

Gestational diabetes mellitus (GDM)

GDM is glucose intolerance first recognized during pregnancy. India has a high prevalence (10-15% of pregnancies) due to genetic predisposition and changing dietary patterns.

DIPSI (Diabetes in Pregnancy Study Group India) criteria: a single non-fasting 75 g oral glucose load with 2-hour plasma glucose >=140 mg/dL diagnoses GDM. This is the recommended screening method in India — simpler than the IADPSG criteria used internationally.

Maternal complications: preeclampsia, polyhydramnios, recurrent infections, future type 2 diabetes (50% risk within 20 years)

Fetal complications: macrosomia (>4 kg), shoulder dystocia, neonatal hypoglycemia (most common neonatal complication — hyperinsulinemia persists after cord clamping), polycythemia, hyperbilirubinemia

Management: medical nutrition therapy (first-line), insulin if targets not met (metformin is increasingly used but insulin remains the standard for NEET PG answers). Target: fasting <95 mg/dL, 2-hour postprandial <120 mg/dL.

Rh isoimmunization

Rh isoimmunization occurs when an Rh-negative mother carries an Rh-positive fetus. Fetal RBCs enter the maternal circulation (fetomaternal hemorrhage), stimulating maternal anti-D IgG antibodies that cross the placenta in subsequent pregnancies and cause hemolytic disease of the fetus and newborn (HDFN).

• Indirect Coombs test detects anti-D antibodies in maternal serum — used for screening Rh-negative mothers
• Direct Coombs test detects antibody-coated fetal/neonatal RBCs — used to diagnose HDFN in the newborn
• Anti-D immunoglobulin (RhoGAM) is given to Rh-negative mothers to prevent sensitization: 300 micrograms IM at 28 weeks (antenatal) and within 72 hours of delivery of an Rh-positive baby. Also given after abortion, ectopic pregnancy, amniocentesis, or any event causing fetomaternal hemorrhage.
• Kleihauer-Betke test quantifies fetal RBCs in maternal blood to determine if additional anti-D doses are needed (for large fetomaternal hemorrhage >30 mL).

Antepartum hemorrhage

Antepartum hemorrhage (APH) is vaginal bleeding after 28 weeks of gestation (some define after 20 weeks). The two major causes — placenta previa and placental abruption — account for >50% of cases and are tested as a differential diagnosis pair in almost every NEET PG paper.

Placenta previa versus placental abruption

Classification of placenta previa (updated):

• Low-lying placenta: placental edge within 2 cm of internal os but does not cover it
• Placenta previa: placenta partially or completely covers the internal os

The old four-type classification (type I-IV) is being replaced, but NBE may still test it:

• Type I (low-lying): lower segment, not reaching os
• Type II (marginal): reaching but not covering os
• Type III (partial): partially covering os
• Type IV (central/complete): completely covering os

The cardinal rule: Never perform a per vaginal examination in a patient with APH until placenta previa has been excluded by ultrasound. A vaginal exam can trigger catastrophic hemorrhage if the examining finger disturbs a previa. This is the single most important management principle and a favorite NEET PG question.

Postpartum hemorrhage

Postpartum hemorrhage (PPH) is blood loss of >=500 mL after vaginal delivery or >=1000 mL after cesarean section. It is the leading cause of maternal mortality worldwide (WHO 2023) and in India (contributing to 27% of maternal deaths, SRS 2020).

The 4 Ts

Management of uterine atony (stepwise)

The stepwise approach to uterine atony is a favorite MCQ sequence:

1. Bimanual uterine compression (rubbing up the uterus) — first step
2. Uterotonics:
   • Oxytocin: 20-40 IU in 1L IV fluid (first-line drug)
   • Ergometrine: 0.2 mg IM/IV (contraindicated in hypertension)
   • Carboprost (15-methyl PGF2-alpha): 0.25 mg IM, repeat every 15 min (max 8 doses). Contraindicated in asthma.
   • Misoprostol: 800-1000 mcg rectal/sublingual (useful where other drugs unavailable)
3. Uterine tamponade: Bakri balloon or condom catheter tamponade
4. Surgical options:
   • Uterine compression sutures (B-Lynch suture)
   • Internal iliac artery ligation (reduces pulse pressure by 85%)
   • Uterine artery embolization
   • Hysterectomy (last resort)

Active management of the third stage of labor (AMTSL) prevents PPH: oxytocin 10 IU IM within 1 minute of delivery, controlled cord traction, and uterine massage. AMTSL reduces PPH risk by 60% (WHO recommendation).

Contraception methods

Contraception contributes 3-4 questions per NEET PG paper. NBE tests mechanism of action, failure rates (Pearl Index), contraindications, and non-contraceptive benefits. Comparison tables are the most efficient way to learn this topic.

Contraception comparison

Emergency contraception

• Levonorgestrel: 1.5 mg single dose within 72 hours (most effective within 24 hours). Delays or inhibits ovulation. Does not disrupt an established pregnancy.
• Ulipristal acetate: 30 mg single dose, effective up to 120 hours (5 days). Selective progesterone receptor modulator.
• Cu-T insertion: most effective method of emergency contraception. Can be inserted up to 5 days after unprotected intercourse. Failure rate <0.1%.

Mifepristone (RU-486) is used for medical termination of pregnancy, not emergency contraception (a common NEET PG trap). It is an antiprogestogen that blocks progesterone receptors, causing decidual necrosis and detachment. Used with misoprostol for MTP up to 9 weeks (MTP Act 2021, India).

Gynecological cancers

Gynecological cancers contribute 3-5 questions per NEET PG. Cervical cancer screening and staging dominate, followed by ovarian tumor classification. NBE tests the screening-to-diagnosis pathway and the clinical features that indicate the tumor type.

Cervical cancer

Cervical cancer is the second most common cancer in Indian women (after breast cancer) with an estimated 123,907 new cases in 2022 (Globocan 2022 data). HPV types 16 and 18 cause approximately 70% of cases.

Screening methods:

• Pap smear (Papanicolaou test): cytological screening. Bethesda system: NILM, ASC-US, LSIL (corresponds to CIN 1), HSIL (corresponds to CIN 2/3), squamous cell carcinoma
• VIA (visual inspection with acetic acid): acetowhite areas on the cervix indicate abnormality. Recommended by WHO for resource-limited settings in India. No lab infrastructure needed.
• HPV DNA testing: highest sensitivity (>95%) for detecting high-risk HPV. WHO now recommends HPV DNA as the primary screening method.

Screening-to-treatment pathway: Abnormal screening result, then colposcopy with directed biopsy, then histological diagnosis, then treatment. This sequence is the most commonly tested pathway.

FIGO staging (2018): cervical cancer is clinically staged (not surgically). Key stages:

• Stage IA: microscopic invasion only (IA1: depth <=3 mm; IA2: depth 3-5 mm)
• Stage IB: clinically visible or microscopic >IA2 (IB1: <=2 cm, IB2: 2-4 cm, IB3: >4 cm)
• Stage IIA: upper 2/3 vagina involved
• Stage IIB: parametrial invasion — this is the stage at which surgery is no longer primary treatment (radiation + chemotherapy becomes the standard)
• Stage III: lower 1/3 vagina (IIIA), pelvic sidewall/hydronephrosis (IIIB), pelvic/para-aortic lymph nodes (IIIC)
• Stage IV: bladder/rectal mucosa (IVA), distant metastases (IVB)

Treatment by stage:

• IA1: conization or simple hysterectomy
• IA2-IB2: radical hysterectomy (Wertheim) + pelvic lymphadenectomy
• IIB and beyond: concurrent chemoradiation (cisplatin-based)

Ovarian tumors

Ovarian tumors are classified by cell of origin:

Krukenberg tumor is a metastatic ovarian tumor (most commonly from gastric cancer) characterized by signet ring cells. Bilateral ovarian enlargement in a patient with GI symptoms should raise suspicion.

PCOD/PCOS

Polycystic ovarian syndrome is the most common endocrine disorder in women of reproductive age, affecting 5-15% of Indian women. NBE tests the diagnostic criteria, hormonal profile, and management.

Rotterdam criteria (2003)

Diagnosis requires 2 of 3:

1. Oligo/anovulation — irregular or absent menstrual cycles (cycle length >35 days or <8 cycles per year)
2. Clinical or biochemical hyperandrogenism — acne, hirsutism (Ferriman-Gallwey score >=8), alopecia, or elevated serum testosterone/DHEAS
3. Polycystic ovarian morphology on ultrasound — 12 or more follicles of 2-9 mm diameter per ovary OR ovarian volume >10 mL

Hormonal profile

Management

• Lifestyle modification: weight loss of 5-10% improves ovulatory function in 55-80% of overweight PCOS patients. This is the first-line intervention.
• For menstrual regulation: combined OCP (provides regular withdrawal bleeding + anti-androgen effect)
• For hirsutism: spironolactone (anti-androgen), OCP with anti-androgenic progestins (cyproterone acetate, drospirenone)
• For ovulation induction (infertility): letrozole is now first-line (NEJM 2014, Legro et al.). Clomiphene citrate is second-line. Gonadotropins if clomiphene-resistant. Laparoscopic ovarian drilling (LOD) is an alternative to gonadotropins.
• For insulin resistance: metformin (improves insulin sensitivity, may restore ovulation in some patients)

Infertility workup

Infertility is defined as failure to conceive after 12 months of regular unprotected intercourse (6 months if female partner is >35 years). It affects approximately 10-15% of couples in India.

Systematic evaluation

The workup evaluates four factors: ovulation, tubal patency, uterine cavity, and male factor (semen analysis).

Ovulation assessment:

• Day 21 serum progesterone (or day 7 post-ovulation): level >3 ng/mL confirms ovulation. This is the single most reliable ovulation marker for NEET PG.
• Basal body temperature (BBT): biphasic pattern (rise of 0.5 degrees Celsius after ovulation due to progesterone). Retrospective confirmation only.
• Ultrasound follicular monitoring: tracks dominant follicle growth (mature follicle: 18-22 mm) and confirms ovulation (follicle collapse, free fluid in pouch of Douglas)

Tubal patency:

• Hysterosalpingography (HSG): gold standard outpatient test. Radio-opaque dye injected through cervix; bilateral peritoneal spillage confirms tubal patency. Performed in the proliferative phase (day 7-10) to avoid disrupting early pregnancy.
• Diagnostic laparoscopy with chromopertubation: gold standard for tubal assessment. Methylene blue dye injected through cervix; observed spilling from fimbriae confirms patency. Also allows assessment of endometriosis, adhesions, and tubal pathology.

Semen analysis (WHO 2021 criteria):

Semen analysis is performed after 2-7 days of abstinence. Abnormal results require confirmation with a repeat sample after 3 months (one spermatogenesis cycle is approximately 74 days). Male factor contributes to infertility in 30-40% of couples.

Assisted reproduction indications:

• IUI (intrauterine insemination): unexplained infertility, mild male factor, cervical factor
• IVF (in vitro fertilization): bilateral tubal blockage, severe male factor, failed IUI (3-6 cycles), advanced maternal age, endometriosis
• ICSI (intracytoplasmic sperm injection): severe oligospermia, obstructive azoospermia (after surgical sperm retrieval)

Cross-reference with Medicine high-yield topics for endocrine overlap (thyroid disorders in pregnancy, GDM) and with Surgery high-yield topics for surgical management of ectopic pregnancy and ovarian torsion.

Study strategy for OBG

OBG rewards clinical-scenario-based learning. Every topic in this guide translates directly into a clinical vignette in the exam. Build your preparation around case-based MCQ practice rather than textbook reading alone.

Phase 1: Foundation (2 weeks)

Cover the eight areas using DC Dutta's Textbook of Obstetrics (10th edition) and DC Dutta's Textbook of Gynecology (8th edition). Build comparison tables on day 1: previa versus abruption, nephrotic versus nephritic (cross-reference with pediatrics), and contraception methods with failure rates. Solve 15 OBG MCQs daily.

Phase 2: MCQ drilling (2 weeks)

Increase to 25 MCQs daily with mixed obstetric and gynecology topics. For each wrong answer, classify:

1. Diagnostic confusion — you mixed up two conditions with similar presentations
2. Management sequence error — you chose the right treatment but at the wrong step
3. Criteria gap — you did not remember the specific diagnostic criteria (Rotterdam, FIGO staging)

Use spaced repetition for NEET PG to drill the MgSO4 regimen, FIGO staging, and contraception comparison tables.

Phase 3: Revision (1 week)

Revise four tables daily: stages of labor, APH differentiation, PPH management, and contraception comparison. Solve one full-length OBG mock under timed conditions. On exam day, review the MgSO4 Pritchard regimen and partograph rules — these are almost guaranteed marks.

Sources and references

1. DC Dutta, Textbook of Obstetrics, 10th Edition (Konar, 2024) — standard Indian obstetrics textbook for NEET PG.
2. Williams, Obstetrics, 26th Edition (Cunningham et al., 2022) — gold-standard global obstetrics reference.
3. Jeffcoate's Principles of Gynaecology, 9th Edition (Kumar, 2024) — comprehensive gynecology reference for Indian postgraduate exams.
4. WHO, Recommendations on Antenatal Care for a Positive Pregnancy Experience, 2016 — global antenatal care guidelines.
5. FOGSI (Federation of Obstetric and Gynaecological Societies of India) Practice Guidelines, 2023 — Indian-specific management protocols for preeclampsia, GDM, and PPH.
6. Globocan 2022, International Agency for Research on Cancer — cervical cancer incidence data for India.

Frequently asked questions

How many OBG questions appear in NEET PG?

Obstetrics and Gynecology contributes 20-25 questions in NEET PG (2021-2024 analysis). Obstetrics accounts for approximately 12-15 questions and gynecology 8-10. Normal labor, preeclampsia/eclampsia, APH, PPH, and contraception are the top five most tested topics. Gynecological cancers, especially cervical screening, appear with annual regularity.

Which OBG topics are most frequently tested in NEET PG?

Normal labor stages and partograph interpretation top the list. Preeclampsia management (magnesium sulfate regimen), placenta previa versus abruption differentiation, postpartum hemorrhage causes (the 4 Ts), and contraception methods with failure rates are the next tier. In gynecology, cervical cancer screening (Pap smear, VIA, HPV DNA), ovarian tumor classification, and PCOD diagnostic criteria are the most tested.

Should I read Williams or Dutta for NEET PG OBG?

Use DC Dutta's Textbook of Obstetrics as your primary text — it is concise, exam-oriented, and covers Indian clinical practice. Williams Obstetrics is the gold-standard reference but is too detailed for time-efficient NEET PG preparation. Use Williams selectively for topics where mechanism-level understanding is needed — preeclampsia pathophysiology, Rh isoimmunization, and fetal physiology.

How do I differentiate placenta previa from placental abruption in MCQs?

The key discriminators are: placenta previa presents with painless, bright red vaginal bleeding; abruption presents with painful, dark bleeding with a tense tender uterus. In previa the uterus is soft and non-tender; in abruption the uterus is hard (Couvelaire uterus in severe cases). Previa is diagnosed by ultrasound (never do per vaginal exam until previa is excluded). Abruption is a clinical diagnosis.

What is the most important drug to know for eclampsia in NEET PG?

Magnesium sulfate is the drug of choice for both prevention (in severe preeclampsia) and treatment of eclampsia. Know the Pritchard regimen: loading dose 4g IV + 5g IM in each buttock, then 5g IM every 4 hours. Therapeutic range is 4-7 mEq/L. Toxicity signs: loss of patellar reflex (first), respiratory depression, cardiac arrest. Antidote is calcium gluconate.

What are the 4 Ts of postpartum hemorrhage?

The 4 Ts are: Tone (uterine atony, 70%, most common), Tissue (retained products, 20%), Trauma (lacerations, 9%), and Thrombin (coagulopathy, 1%). Uterine atony is managed by bimanual compression, oxytocin, ergometrine, and carboprost. The stepwise approach from drugs to tamponade to surgery is a favorite MCQ sequence.

How is PCOD diagnosed according to the Rotterdam criteria?

The Rotterdam criteria (2003) require 2 of 3: oligo/anovulation, clinical or biochemical hyperandrogenism, and polycystic ovarian morphology on ultrasound (12 or more follicles of 2-9 mm or ovarian volume >10 mL). The LH:FSH ratio is elevated (>2:1). NBE tests the criteria, hormonal profile, and the association with insulin resistance.

What is the best strategy for last-minute OBG revision before NEET PG?

In the final two weeks, revise four tables daily: stages of labor with cardinal movements, preeclampsia versus eclampsia management, APH differentiation (previa versus abruption), and contraception comparison with failure rates. Solve 20-25 OBG MCQs daily under timed conditions. On exam day, review the partograph interpretation rules and the MgSO4 regimen.

Start your OBG prep today. Open the Obstetrics and Gynecology subject page and solve your first 15 MCQs — the clinical scenarios you practice now are the marks you will collect on exam day. Want unlimited AI-powered OBG MCQs with detailed explanations? Explore NEETPGAI Pro.

Looking for a structured study timeline? Build your personalized NEET PG study plan that integrates OBG with your other subjects.

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Written by: NEETPGAI Editorial Team Reviewed by: Pending SME Review Last reviewed: April 2026

This article is reviewed by qualified medical professionals for clinical accuracy and exam relevance. For corrections or updates, contact the editorial team.