Tests, scans and checks

NHS Pregnancy Tests and Scans Explained: Timing, Purpose, and Results

Welcome to your mothernity comprehensive guide to the NHS pregnancy tests and scans explained. The UK antenatal care system involves a series of routine tests designed to safeguard both your health and the development of your baby. This resource demystifies every common check, helping you move from anxiety to confidence at every appointment.

Our Content Promise & Safety Disclaimer

This guide is rigorously aligned with current NHS guidance on antenatal care, providing factual and accurate procedure details.

DISCLAIMER: This content is for informational purposes only. Results and protocols may vary based on individual circumstances and local NHS Trust procedures. Always direct specific questions to your midwife or consultant.

Initial Screening and Booking Checks

The first set of appointments establishes your baseline health and identifies any potential risks. These checks, primarily performed during your booking appointment (usually around 8–12 weeks), are foundational for your entire care plan.

The Booking Appointment and Initial Blood Tests

This is your first detailed meeting with your midwife. A series of initial blood tests are taken to check your blood group, Rhesus factor, iron levels (for anaemia), and screen for conditions like Rubella immunity, Hepatitis B, and HIV. Understanding these initial results is key to planning preventative care.

Your First GP Appointment

Combined Screening for Conditions

You will be offered a combined screening for Down syndrome, Edward’s syndrome, and Patau’s syndrome. This screening combines results from a blood test and an early ultrasound, providing you with probability results.

Key Ultrasound Scans

Ultrasound scans are non-invasive procedures that allow you to see your baby and allow clinicians to check development.

The Dating Scan (Around 12 Weeks)

This scan determines your estimated due date, checks if you are carrying one baby or multiples, and confirms the baby’s growth. This is also the scan used for the first part of the combined screening for some conditions.

12-week Dating Scan

The Anomaly Scan (Around 20 Weeks)

This is the most detailed scan, thoroughly examining your baby’s anatomy—from the heart and spine to the brain and kidneys. The purpose is to check for physical abnormalities and to ensure the placenta and amniotic fluid levels are normal.

20-week Anomaly Scan

Routine Checks and Late Pregnancy Screenings

As your pregnancy progresses, monitoring shifts to weekly and bi-weekly checks focused on growth and late-stage safety.

Routine Monitoring at Midwife Appointments

Every midwife appointment involves monitoring your blood pressure and checking your urine (for protein, which can signal pre-eclampsia). The midwife will also measure your tummy (fundal height) to ensure the baby is growing on track.

Your First GP Appointment

Late-Stage Screening and Tests

If risk factors are present, you may be offered late-stage tests. These can include a Gestational Diabetes screen (GTT) and the Group B Strep (GBS) test, though GBS testing is not routinely offered across all NHS trusts. Understanding the criteria for these helps you advocate for your care.

Conclusion: Motherhood Made Easy

Being well-informed about your NHS pregnancy tests and scans helps you fully participate in your care. By staying vigilant and attending every appointment, you are taking the best possible steps to safeguard your health and your baby’s journey.

Visit our Pregnancy Page for holistic advice | Visit our Labour & Birth for a guide on monitoring in the delivery room.