Pregnancy Scans – Which Scans Are Necessary During Pregnancy?
Pregnancy is one of the most beautiful journeys a woman can experience — and also one that requires careful medical attention. Among the most important aspects of antenatal care are pregnancy scans, which allow doctors to monitor your baby’s growth, detect any complications early, and give you peace of mind at every stage.
But with so many different types of scans available, many expectant mothers ask: Which pregnancy scans are actually necessary? When should I get them? And what do they show?
This guide answers all of that — in simple, easy-to-understand language.
What Are Pregnancy Scans?
Pregnancy scans (also called obstetric ultrasounds) use high-frequency sound waves to create real-time images of your baby inside the womb. They are completely safe for both mother and baby — no radiation is involved.
These scans help doctors:
- Confirm the pregnancy and check the heartbeat
- Measure the baby’s size and growth
- Detect structural abnormalities
- Monitor the placenta, amniotic fluid, and umbilical cord
- Identify the baby’s position before delivery
The number and timing of pregnancy scans may vary depending on your health, risk factors, and the guidelines followed by your doctor or fertility specialist.
How Many Scans Are Done During Pregnancy?
In a healthy, low-risk pregnancy, most doctors recommend 3 to 4 essential scans. However, women with complications, fertility treatments, or high-risk pregnancies may require additional monitoring.
Let’s look at each scan in detail.
1. Early Pregnancy Scan (Viability Scan) – 6 to 9 Weeks
What it is: Also called a transvaginal ultrasound or dating scan, this is often the very first scan a woman receives.
What it checks:
- Confirms the pregnancy is inside the uterus (rules out ectopic pregnancy)
- Detects the baby’s heartbeat
- Determines how many embryos are present (especially important after IVF)
- Estimates the gestational age and due date
Who needs it: Women who conceived through IVF, those experiencing bleeding or pain, or anyone who wants early confirmation.
If you’ve undergone fertility treatment, your doctor — such as a Best IVF Specialist in Jaipur — will likely schedule this scan around 6–7 weeks to confirm a successful implantation.
2. NT Scan (Nuchal Translucency Scan) – 11 to 14 Weeks
What it is: One of the most important first-trimester pregnancy scans, the NT scan is a screening tool for chromosomal abnormalities.
What it checks:
- Measures the fluid at the back of the baby’s neck (nuchal fold)
- Screens for Down’s Syndrome (Trisomy 21), Edwards Syndrome (Trisomy 18), and Patau Syndrome (Trisomy 13)
- Evaluates fetal nasal bone
- Checks early fetal anatomy
Accuracy: When combined with blood tests (Double Marker Test), the NT scan is about 85–90% accurate in detecting chromosomal risks.
Is it mandatory? It is strongly recommended for all pregnant women, especially those over 35 years of age.
3. Anomaly Scan (Level 2 Ultrasound / TIFFA Scan) – 18 to 22 Weeks
What it is: This is the most comprehensive of all routine pregnancy scans. TIFFA stands for Targeted Imaging for Fetal Anomalies.
What it checks:
- Complete structural survey of the baby (brain, spine, heart, kidneys, limbs, face)
- Detects birth defects or developmental abnormalities
- Evaluates placental position
- Checks amniotic fluid levels
- Measures fetal growth parameters
Why it matters: This is your best window to detect major structural issues while there is still time for informed decision-making or early intervention.
Duration: Usually 30–45 minutes.
4. Growth Scan (Third Trimester Scan) – 28 to 32 Weeks
What it is: As your baby grows, the growth scan helps ensure everything is on track in the third trimester.
What it checks:
- Baby’s weight and size estimation
- Position of the baby (head-down, breech, transverse)
- Placental location and maturity
- Amniotic fluid index (AFI)
- Blood flow through the umbilical cord (Doppler study)
Who needs it: All pregnant women benefit from at least one growth scan in the third trimester. Those with gestational diabetes, hypertension, or multiple pregnancies may need more frequent monitoring.
5. Doppler Scan – As Recommended
What it is: A Doppler ultrasound measures blood flow between the placenta and baby through the umbilical cord.
What it checks:
- Whether the baby is getting adequate oxygen and nutrients
- Signs of fetal distress
- Placental insufficiency
When it’s done: Usually between 28 and 34 weeks, or whenever the doctor suspects restricted fetal growth.
6. Pre-Labour Scan – 36 to 40 Weeks
What it is: Done close to the due date, this final pregnancy scan helps prepare for delivery.
What it checks:
- Baby’s final position (head-down vs breech)
- Placenta location — rules out placenta previa
- Amniotic fluid levels
- Estimated birth weight
This scan helps your doctor decide whether a vaginal delivery or caesarean section is more appropriate.
Summary Table: All Pregnancy Scans at a Glance
| Scan Name | Timing | Purpose |
|---|---|---|
| Early / Viability Scan | 6–9 weeks | Confirm pregnancy, heartbeat, rule out ectopic |
| NT Scan | 11–14 weeks | Screen for chromosomal abnormalities |
| Anomaly Scan (TIFFA) | 18–22 weeks | Detailed structural survey of the baby |
| Growth Scan | 28–32 weeks | Monitor growth, fluid, placenta |
| Doppler Scan | 28–34 weeks | Check blood flow & fetal wellbeing |
| Pre-Labour Scan | 36–40 weeks | Check position, plan delivery |
Additional Scans for High-Risk Pregnancies
Women with certain conditions may require more frequent or specialised pregnancy scans, including:
- 3D/4D Ultrasound — Provides detailed three-dimensional images of the baby; often used for facial anomaly assessment
- Fetal Echocardiography — A specialised scan of the baby’s heart, recommended if there’s a family history of heart defects
- Cervical Length Scan — Done between 18–24 weeks to assess the risk of preterm labour
- Biophysical Profile (BPP) — Combines ultrasound with fetal heart rate monitoring; used in high-risk third trimesters
Are Pregnancy Scans Safe?
Yes. Ultrasound-based pregnancy scans use sound waves — not X-rays or radiation — and have been used safely in obstetric care for over five decades. There is no scientific evidence of harm to the mother or baby from routine diagnostic ultrasound when performed by a trained medical professional.
When Should You Be Extra Cautious?
While scans are generally safe, you should consult your doctor promptly if you experience:
- Vaginal bleeding at any stage
- Sudden reduction in fetal movements
- Severe abdominal pain or cramping
- Swelling in hands, face, or feet
- Persistent headaches or visual disturbances
These symptoms may require an unscheduled scan for immediate evaluation.
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Role of Pregnancy Scans in IVF and Assisted Reproduction
For women undergoing IVF or other assisted reproductive technologies, pregnancy scans take on an even greater role. From the very first early viability scan at 6–7 weeks to monitor embryo implantation, to the NT scan and beyond — close ultrasound monitoring is a routine part of post-IVF pregnancy care.
A qualified and experienced specialist can guide you through every step. If you’re in Rajasthan and looking for expert support, consulting the Best IVF Specialist in Jaipur ensures that your pregnancy journey — whether natural or assisted — is monitored with the highest standard of care.
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Frequently Asked Questions (FAQs) About Pregnancy Scans
Q1. How many pregnancy scans are required in total?
A minimum of 3 to 4 scans are recommended for a healthy pregnancy: the early viability scan, NT scan, anomaly scan, and a third-trimester growth scan. High-risk pregnancies may require more.
Q2. Is the anomaly scan (TIFFA) mandatory?
While not legally mandatory, the anomaly scan is strongly recommended by all major obstetric bodies. It is the most comprehensive scan to detect structural issues in the baby.
Q3. Can I find out the baby’s gender through a pregnancy scan?
In India, revealing the sex of the foetus through ultrasound is prohibited under the Pre-Conception and Pre-Natal Diagnostic Techniques (PCPNDT) Act. Doctors and sonographers are not permitted to disclose this information.
Q4. What is the difference between a 2D, 3D, and 4D scan?
A 2D scan shows flat, two-dimensional images and is used for all routine diagnostic purposes. A 3D scan creates three-dimensional still images. A 4D scan shows three-dimensional images in real time (like a video). 3D and 4D scans are often used for detailed facial or structural evaluations.
Q5. Are pregnancy scans painful?
No. Abdominal ultrasound scans are completely painless. A transvaginal scan (used in early pregnancy) may cause mild discomfort but is not painful.
Q6. What happens if an abnormality is found on a pregnancy scan?
If an abnormality is detected, your doctor will discuss further diagnostic options such as amniocentesis, chorionic villus sampling (CVS), or fetal echocardiography, and guide you through the next steps with counselling support.
Q7. Can I skip the NT scan if I’m young and healthy?
Even for young, healthy women, the NT scan provides valuable information about chromosomal health. Skipping it means missing an important early screening window. Most doctors recommend it for all pregnant women, regardless of age.
Final Thoughts
Pregnancy scans are not just routine checkboxes — they are windows into your baby’s world. Each scan at each trimester serves a specific, medically important purpose, and together they form the backbone of safe antenatal care.
Whether you are pregnant naturally or through fertility treatment, working with a skilled and experienced specialist makes all the difference. Regular monitoring, timely scans, and expert guidance are what ensure a healthy pregnancy and a safe delivery.
If you have questions about pregnancy care, scans, or fertility treatment, reach out to the Best IVF Specialist in Jaipur for personalised, compassionate guidance every step of the way.
Disclaimer: This article is intended for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for personalised guidance during pregnancy.
