Maternal Serum Screening

Canterbury Health Laboratories, along with LabPlus in Auckland, provide a Ministry of Health funded national screening program for Down Syndrome (also called Trisomy 21). This is a genetic condition that can happen by chance, and affects around 1 in 700 pregnancies. There are also two other genetic conditions (Edwards and Patau syndromes) that are screened for using these tests. Since these disorders are rarer, the tests are often known simply as Down Syndrome screening. 

Down Syndrome screening tests are available to all pregnant women in New Zealand, but they are optional, and you may choose whether or not to be tested.

Two types of tests are offered:

Maternal serum screening first trimester or ‘combined screening test’

This is performed between 9 and 14 weeks 6 days, and involves having a blood test and a ‘nuchal translucency’ (NT) ultrasound.  This is the most common test currently performed in Aotearoa New Zealand.

Maternal serum screening second trimester

This is performed between 14 and 20 weeks, and involves a single (free) blood test. This is usually only suggested if you book in for pregnancy care after 14 weeks of pregnancy.

The maternal serum team of six staff are there to help and often liaise with midwives, sonographers and referring laboratories to provide the highest quality of screening possible.

The Maternal Serum team of six staff are here to help. They often liaise with midwives, sonographers and referring laboratories to provide the highest quality of screening possible.

Learn more about the maternal serum screening tests offered