Comparing Provincially Funded and Privately Paid Screening Tests

All pregnant women in BC with BC Health Care (MSP) coverage can choose to have prenatal genetic screening. How far along you are in your pregnancy, your age, your health and family history and whether or not you are carrying more than one baby will influence which screening tests are available to you. More information regarding the prenatal screening tests available to women in BC can be found at "What are the different prenatal screens?"

Some women may choose to pay privately for First Trimester Screening (FTS). FTS involves the NT ultrasound (and possibly other ultrasound measurements depending on the centre) and 1 blood test. The ultrasound and blood test both occur between 11 and just under 14 weeks. A result is available after both the blood test and ultrasound are done.

No screening test is perfect and none will give a definite answer. Regardless of the test, a screen positive result will require a diagnostic test (amniocentesis or chorionic villi sampling) to get a definite answer.

The tests can be compared from many points of view:

1. Performance of the tests: With IPS, patients have the lowest chance of having a false positive test or in other words, screening positive when in fact the baby does not have Down syndrome. The chance of a false positive is comparable for SIPS and FTS. For all three tests (IPS, SIPS and FTS), women (as a group) who have a screen negative have a chance of having a baby with Down syndrome of less than 1 in 1000.
2. Availability/access: For SIPS, blood tests can be done in any laboratory. For IPS, the blood tests are done in any lab and the NT ultrasound is available through numerous sites throughout the province. For FTS, there are a limited number of private clinics which offer this service.
3. Timing of results: Results for SIPS and IPS are available after the second blood test - at the end of the 16th week of pregnancy at the earliest. Results of FTS could be available as early as the 11th week of pregnancy depending on when the test is done.
4. Cost: SIPS and IPS are covered by BC Health Care (MSP) so there is no cost for the patient. The cost of FTS varies between centers and is approximately $500.

All women with a screen positive result will be offered a diagnostic test.

Women who screen positive by FTS may be offered chorionic villi sampling (CVS) which is only available in the Lower Mainland or an amniocentesis which is available at many hospitals around the province. Women who screen positive by IPS or SIPS would be offered an amniocentesis.

Both CVS and amniocentesis are covered by MSP for women who screen positive. Results from a CVS or amniocentesis will tell whether the pregnancy is truly affected or not. Results from these tests can take about 2 weeks. Regardless of whether the test done is a CVS or an amniocentesis, the same options are available to women who are found to have an affected pregnancy.