Antenatal Care & Booking Visit

Antenatal care (ANC) is the systematic supervision of a pregnant woman from conception to the onset of labour, aimed at early detection and management of complications, health promotion, and birth preparedness. NEET PG loves trimester-wise vignettes — "what test at which gestational age" — so anchoring the schedule and cut-offs is the fastest route to easy marks.

Definition & Goals

Antenatal care is the planned examination, observation, and guidance of the gravida during pregnancy. The classical objectives are to:

• Promote, protect and maintain the health of the mother during pregnancy.
• Detect "high-risk" cases early and give them special attention.
• Foresee complications and prevent them (e.g. anaemia, pre-eclampsia, preterm labour).
• Ensure a healthy mother delivering a healthy baby.
• Educate the mother regarding nutrition, breastfeeding, family planning and danger signs.

High-yield: The single most important purpose of ANC is early identification and management of high-risk pregnancy. Reducing maternal and perinatal morbidity/mortality is the ultimate outcome.

Visit Schedule — Old vs New

The traditional schedule and the newer WHO model are both examinable, and examiners deliberately exploit the confusion between them.

Model	Total visits	Schedule
Traditional (ICMR/old WHO FANC)	Up to ~14 visits	Monthly till 28 weeks → fortnightly 28–36 weeks → weekly after 36 weeks till delivery
WHO 2002 Focused ANC (FANC)	4 visits	~16, 24–28, 32, 36 weeks
WHO 2016 (current)	8 contacts	12, 20, 26, 30, 34, 36, 38, 40 weeks
India — Government of India (RCH)	Minimum 4 visits	1st: before/within 12 weeks; 2nd: 14–26 wk; 3rd: 28–34 wk; 4th: 36 wk–term

High-yield: WHO 2016 increased the recommended number from 4 "visits" to 8 "contacts" — the change from "visit" to "contact" is itself a favourite MCQ point, made because the 4-visit model was associated with more perinatal deaths.

High-yield: Under the Indian programme (PMSMA — Pradhan Mantri Surakshit Matritva Abhiyan), a free, fixed-day check-up is provided on the 9th of every month in the 2nd and 3rd trimesters.

Flow of the first contact: Confirm pregnancy → confirm gestational age (LMP/USG) → detailed history → general & obstetric examination → baseline investigations → risk stratification → counselling & supplementation → schedule next contact.

The Booking Visit

The booking (first) visit ideally occurs before 12 weeks (first trimester). It is the most information-dense visit and the commonest vignette setting.

History to elicit: menstrual history (to fix LMP and EDD), obstetric history (parity, prior LSCS, abortions, stillbirth, congenital anomaly), medical history (diabetes, hypertension, cardiac, thyroid, epilepsy), drug/teratogen exposure, and family history.

Estimated date of delivery (EDD) by Naegele's rule = LMP + 9 calendar months + 7 days (or − 3 months + 7 days + 1 year). It assumes a regular 28-day cycle and ovulation on day 14; adjust for longer/shorter cycles.

High-yield: The most accurate method to date a pregnancy is first-trimester crown–rump length (CRL) on ultrasound (accurate to ±5–7 days). Beyond the first trimester, dating accuracy falls.

Examination at booking: height, weight (and BMI), blood pressure, pallor, pedal oedema, thyroid, breast, cardiovascular and respiratory systems, and abdominal/obstetric examination as appropriate for gestation.

High-yield: A maternal height < 140 cm is a marker of possible contracted pelvis / cephalopelvic disproportion. Booking weight establishes the baseline for monitoring gain (recommended total gain ~11–16 kg for normal BMI).

Investigations — The Core Exam Topic

Booking / first-trimester panel

• Haemoglobin and complete blood count.
• Blood group and Rh typing (with indirect Coombs test if Rh-negative).
• Blood sugar (and screening for gestational diabetes).
• Urine routine — protein and sugar; urine culture for asymptomatic bacteriuria.
• HIV, HBsAg, VDRL (syphilis) — the routine "infection screen".
• Thyroid-stimulating hormone (TSH) where indicated.

Investigation	Timing / cut-off worth remembering
Haemoglobin (WHO)	Anaemia in pregnancy if < 11 g/dL; India (NFHS) uses < 11. Severe < 7 g/dL
Oral glucose tolerance (GDM)	IADPSG one-step 75 g OGTT: fasting ≥ 92, 1 h ≥ 180, 2 h ≥ 153 mg/dL (any one positive)
GoI DIPSI test	75 g glucose, 2-h value ≥ 140 mg/dL = GDM (non-fasting, single value)
Indirect Coombs (Rh-neg)	At booking and ~28 weeks
Anti-D prophylaxis	28 weeks (routine antenatal) and within 72 h of delivery of Rh-positive baby

High-yield: The DIPSI (Diabetes in Pregnancy Study Group India) test is performed irrespective of the last meal: give 75 g oral glucose and check the 2-hour plasma glucose; ≥ 140 mg/dL diagnoses GDM. This is the GoI-recommended single-step test and a repeated favourite.

High-yield: Screening for asymptomatic bacteriuria with urine culture in early pregnancy is mandatory because untreated bacteriuria progresses to pyelonephritis and is linked to preterm labour and low birth weight.

Ultrasound schedule

• 6–9 weeks — viability, dating (CRL), number of fetuses, chorionicity in twins.
• 11–13⁺⁶ weeks — nuchal translucency (NT) + combined first-trimester aneuploidy screen.
• 18–20 weeks — anomaly (TIFFA) scan — the single most important structural scan.
• Third trimester — growth, liquor, placental localisation, Doppler if indicated.

High-yield: Increased nuchal translucency (≥ 3 mm) at 11–14 weeks is associated with Down syndrome (trisomy 21) and cardiac anomalies. The "combined test" = NT + maternal serum free β-hCG (high) + PAPP-A (low) in trisomy 21.

Maternal serum screening (aneuploidy)

Test	Window	Trisomy 21 pattern
Combined (1st trimester)	11–13⁺⁶ wk	↑NT, ↑β-hCG, ↓PAPP-A
Triple test	15–18 wk	↓AFP, ↑hCG, ↓uE3
Quadruple test	15–18 wk	↓AFP, ↑hCG, ↓uE3, ↑inhibin A
Cell-free fetal DNA (NIPT)	from 10 wk	Highest sensitivity, a screen not a diagnosis

High-yield: Maternal serum AFP is RAISED in open neural tube defects (and abdominal wall defects, multiple gestation) and LOW in trisomy 21. NIPT is the most sensitive screen but amniocentesis/CVS remains diagnostic.

TORCH Screening & Infection Counselling

TORCH = Toxoplasma, Others (syphilis, varicella, parvovirus B19, HIV), Rubella, Cytomegalovirus, Herpes simplex.

High-yield: Routine universal TORCH screening is NOT recommended in low-risk pregnancy — it is reserved for suggestive findings (e.g. IUGR, hydrops, intracranial calcification, microcephaly on USG, or maternal seroconversion). Interpretation rests on IgM (recent) vs IgG (past) and IgG avidity (low avidity = recent infection).

• Rubella in the first trimester → congenital rubella syndrome (cataract, sensorineural deafness, PDA). MMR is a live vaccine — contraindicated in pregnancy; vaccinate susceptible women postpartum.
• CMV is the commonest congenital infection → sensorineural hearing loss, periventricular calcification.
• Toxoplasmosis → intracranial calcification (diffuse), hydrocephalus, chorioretinitis; treat with spiramycin.

Supplementation & Immunisation

• Iron–folic acid (IFA): GoI advises folic acid alone in the first trimester, then IFA after 12 weeks. Folic acid 400 µg/day periconceptionally reduces neural tube defects; 4–5 mg/day if previous NTD baby or on antiepileptics. India's prophylactic dose: 60 mg elemental iron + 500 µg folic acid daily for ≥ 180 days antenatally (and continued 180 days postpartum).
• Calcium: 1 g/day from 14 weeks (WHO) to reduce pre-eclampsia in low-intake populations; GoI gives calcium 1 g/day.
• Tetanus–diphtheria (Td): two doses 4 weeks apart in the first pregnancy (or a single booster if previously immunised). First dose as early as possible, second at least 4 weeks before delivery.

High-yield: Live vaccines (MMR, varicella, oral polio, BCG) are contraindicated in pregnancy. Inactivated vaccines such as Td, influenza, hepatitis B are safe and recommended.

Counselling at the Booking Visit

• Nutrition: an additional ~350 kcal/day in 2nd & 3rd trimesters and ~600 kcal during lactation; adequate protein.
• Danger signs the woman must report immediately: bleeding per vaginum, severe headache/blurred vision, reduced fetal movements, leaking, fever, persistent vomiting, swelling of face/hands, convulsions.
• Avoid alcohol, tobacco, and unprescribed drugs; review teratogens.
• Birth preparedness, institutional delivery, breastfeeding promotion, and contraception counselling.

Risk Stratification — "High-Risk Pregnancy"

Identifying high-risk pregnancy is the operational goal of ANC. Flags include: age < 18 or > 35 years; height < 140 cm; grand multipara; previous LSCS, stillbirth or recurrent abortion; Rh-negative mother; medical disorders (anaemia, diabetes, hypertension, cardiac, thyroid); multiple gestation; malpresentation; and antepartum haemorrhage.

Risk approach: Identify risk factor → escalate frequency of contacts → targeted investigations → refer to higher centre / specialist → plan place & mode of delivery.

Common Complications Detected Through ANC

• Anaemia — commonest medical disorder in Indian pregnancy; iron-deficiency type predominates.
• Hypertensive disorders / pre-eclampsia — BP and urine protein at every visit; calcium and low-dose aspirin (from 12–16 weeks in high-risk) for prevention.
• Gestational diabetes — screened as above; macrosomia, polyhydramnios, neonatal hypoglycaemia if missed.
• Rh isoimmunisation — prevented by anti-D.
• Fetal growth restriction / macrosomia, malpresentation, and preterm labour.

High-yield: Low-dose aspirin (75–150 mg/day) started before 16 weeks reduces pre-eclampsia in high-risk women — the timing (before 16 weeks) is the testable point.

Key Differentials / Distinctions

Confusable pair	Discriminator
FANC 4-visit vs WHO 2016 8-contact	2016 model uses contacts, improves outcomes
Combined vs Quadruple test	Combined = 1st trimester (NT-based); Quadruple = 2nd trimester (4 markers)
↑ vs ↓ maternal AFP	↑ = open NTD; ↓ = Down syndrome
DIPSI vs IADPSG	DIPSI = single 2-h ≥ 140, non-fasting; IADPSG = fasting + 1 h + 2 h
Anti-D at 28 wk vs postpartum	Antenatal prophylaxis at 28 wk; postnatal within 72 h

Recently asked / exam angle

• "A pregnant woman comes at 12 weeks — which is the best investigation to confirm gestational age?" → CRL on ultrasound.
• "GoI-recommended test for GDM screening?" → DIPSI: 75 g glucose, 2-h ≥ 140 mg/dL.
• "When is anti-D given antenatally to an Rh-negative woman?" → 28 weeks, and within 72 h post-delivery of an Rh-positive baby.
• "Number of antenatal contacts recommended by WHO (2016)?" → 8.
• "Marker raised in open neural tube defect?" → maternal serum AFP.
• "Best time for anomaly scan?" → 18–20 weeks.
• Vignette of IUGR + intracranial calcification → think TORCH (CMV/toxoplasma), not routine screening.
• "Folic acid dose for woman with previous NTD baby?" → 4–5 mg/day.

Rapid revision

1. Booking visit ideally before 12 weeks; first trimester is most investigation-dense.
2. EDD by Naegele's rule = LMP − 3 months + 7 days + 1 year.
3. CRL is the most accurate dating method; anomaly (TIFFA) scan at 18–20 weeks.
4. WHO 2016 = 8 contacts (12, 20, 26, 30, 34, 36, 38, 40 weeks); GoI minimum 4 visits.
5. PMSMA clinics on the 9th of every month for 2nd/3rd-trimester women.
6. Anaemia in pregnancy = Hb < 11 g/dL; severe < 7.
7. DIPSI: 75 g glucose, 2-h ≥ 140 mg/dL = GDM, non-fasting.
8. Increased NT (≥3 mm) → trisomy 21; combined test = ↑β-hCG, ↓PAPP-A, ↑NT.
9. Maternal AFP ↑ in open NTD, ↓ in Down syndrome.
10. Anti-D at 28 weeks and within 72 h postpartum (Rh-negative mother, Rh-positive baby).
11. Periconceptional folic acid 400 µg (4–5 mg if prior NTD/antiepileptics); Td 2 doses in first pregnancy.
12. Live vaccines (MMR, varicella, OPV) contraindicated; low-dose aspirin before 16 weeks prevents pre-eclampsia.