When to Do Sonography (Ultrasound) During Pregnancy

Simple, evidence-informed guide from Matrutvam Women’s Multispeciality Hospital. This is educational; your obstetrician will personalise your schedule.

Ultrasound uses sound waves (no radiation) to check your baby’s growth and your pregnancy’s safety. Most pregnancies need 2–3 key scans; some need a few extras.

The usual scan schedule

1) Early “dating/viability” scan 6–9 weeks

• Confirms the pregnancy is in the uterus

• Checks heartbeat, number of babies, and dates the pregnancy

• Helpful if you have pain, spotting, IVF, or uncertain last period

2) NT (nuchal translucency) / first-trimester scan 11–14 weeks

• Measures NT at the baby’s neck and checks the nasal bone

• Screens for some chromosomal conditions (often with blood tests)

• Reviews early anatomy and placenta location

3) Anomaly (anatomy) scan 18–22 weeks

• A detailed head-to-toe check of organs, spine, limbs, placenta, and cord

• Dates are important: this is the best window to pick up most structural problems

4) Growth ± Doppler scans 28–32 weeks and/or 32–36 weeks (as needed)

• Checks baby’s size, fluid, movements, and blood flow in placenta/cord

• Common if you have high BP, diabetes, twins, reduced movements, or baby measuring small/large

5) Late-pregnancy well-being scans from 36 weeks (if advised)

• Biophysical profile (BPP) or ultrasound with NST to plan safe timing of birth

• Re-checks placenta position (especially if it was “low-lying” earlier)
  

Special scans (only if needed)

• Cervical-length scan (16–24 wks): if you had prior preterm birth or short cervix

• Fetal echocardiography (18–24 wks): detailed heart scan for higher-risk pregnancies (e.g., diabetes, IVF, increased NT, family history)

• Targeted follow-ups: if any earlier scan showed a concern

When to get an extra scan quickly

• Vaginal bleeding, fluid leak, or strong abdominal pain

• Severe headache/blurred vision with high BP

• Baby’s movements are less than usual (after 28 weeks)

• Belly size not matching dates, or your doctor is worried about growth

Safety, prep, and tips

• Ultrasound is considered safe in pregnancy when medically indicated.

• Early scans may need a partly full bladder; later ones usually don’t.

• Bring past reports; wear a two-piece outfit for easy access.

• Exact timing can change with your cycle, symptoms, twins, IVF, or medical history follow your doctor’s dates.

FAQs

How many scans are “too many”? We avoid unnecessary scans, but do not delay a scan if there’s a medical reason benefits outweigh risks.
Can ultrasound tell my baby’s sex? Sex determination is illegal in India; our focus is health and safety.
Do I need NIPT if my NT scan is normal? Not always. Your clinician will advise based on age, history, and combined screening results.

For a clear, personalised scan plan and same-day reports learn more at matrutvamhospitals.com.