Pregnancy scans and tests on the NHS

What happens at the booking appointment?

The booking appointment is the first main antenatal visit, and the NHS gives the usual timing as between 8 and 12 weeks. The midwife checks blood pressure and urine and offers a blood group test.

Blood is also taken at or around this time. NHS trusts describe booking-stage blood tests for HIV, syphilis, hepatitis B, sickle cell and thalassaemia, and the exact list can vary between trusts.

What is the dating scan?

The dating scan is an ultrasound scan, usually offered at 11 to 14 weeks. It estimates when the baby is due from the baby's measurements.

Is screening for Down's, Edwards' and Patau's syndromes compulsory?

Taking part in this screening is a choice. If a person chooses it, the combined test pairs a blood test taken between 10 and 14 weeks with a measurement of the fluid at the back of the baby's neck, taken during the dating scan.

Edwards' and Patau's syndromes are also looked for at the mid-pregnancy scan if the person chooses screening. A blood test called the quad test, taken between 14 and 20 weeks, can be used for Down's syndrome when the combined test was not possible. It is less accurate than the combined test.

What does the mid-pregnancy anomaly scan look at?

The anomaly scan is an ultrasound that checks for 11 physical conditions in the baby and the position of the placenta, though not every condition can be found. The NHS lists it as usually between 18 and 21 weeks, and some trusts describe it as taking place between 20 and 22 weeks.

Screening for Edwards' and Patau's syndromes forms part of this scan for those who choose it.

What if a screening result says there is a higher chance?

A higher-chance result is not a diagnosis. The options described are a more accurate screening blood test, called the non-invasive prenatal test or NIPT, a diagnostic test such as chorionic villus sampling or amniocentesis, or no further tests.

The NHS summary says there are no known risks to the pregnant person or the baby from the blood tests or scans used for this screening. Diagnostic tests, such as chorionic villus sampling or amniocentesis, are different from screening and can give a definite answer. If the screening finds something, the person is contacted sooner.

For urgent concerns in pregnancy, the midwife, maternity unit or NHS 111 can advise, and 999 is for emergencies.