Understanding Screening Options

Sometimes, the worry about a healthy pregnancy can take away from the joy of actually being pregnant. PCRM is here as a resource to women and their families, and if you have questions about any screening options, please contact the First Trimester Program at any time at: 604 422 7276

Dana Young, Genetic Counselor dyoung@pacificfertility.ca
Ken Seethram, Program Director kseethram@pacificfertility.ca

What is screening?

Screening is a process to figure out the chance that your pregnancy has a particular condition. Generally, screening is applied to such conditions as spinal cord defects, heart and brain defects, genetic syndromes, and other birth defects. Screening usually is a test (like an ultrasound, blood test, or both) which gives you more information about the pregnancy, than before you had the test.

Why should I screen my pregnancy?

For many women, it’s all about being prepared. Screening gives people information, so that they can better adapt to their pregnancies, with confidence and understanding. A good example of screening information is an ultrasound that finds a heart defect in a baby. It’s better to find this out and prepare before the baby is born, rather than being surprised. It’s very hard to be prepared without information.

Why are there so many screening options?

In about 45 countries, first trimester screening using ultrasound and blood tests before 14 weeks is a standard of care. ; In North America, due to some patent and political issues, first trimester screening was not available for a very long time. Because of this, many different screening tests were developed including:

  • quadruple marker screening (the Quad)
  • serum integrated pregnancy screening (SIPS)
  • integrated pregnancy screening (IPS)

What test is best for me?

Each test has its pros and cons. The best test is one which provides you with accurate results in the time you want. If you want an early result (under 14 weeks), the only option is first trimester screening, as the others, do not give you results until 18 weeks, minimum.

What is covered by MSP?

If you are under the age of 35, MSP will cover the SIPS test which is
SIPS = blood at 10-11 weeks, and blood at 16-18 weeks, with an answer at around 18 -20 weeks

If you are 35 and older, MSP will cover the IPS test which is
IPS = SIPS + a Nuchal Translucency (NT) ultrasound test

I qualify for IPS but why can’t I get it?

The problem here in BC, as opposed to Alberta, Ontario, and other provinces, is that the infrastructure is lacking to provide the ultrasound portions of IPS. Why? Training and certification is difficult and requires a motivated, and dedicated group of people, with the appropriate support to achieve the goal. NT performed without certification or outside a dedicated program is simply dangerous to the you and your pregnancy, and is misleading. Also, nasal bone certification (as done in FTS) requires even more training, and experience. Hence, although you may qualify to have an integrated pregnancy screen, you likely will not get it, until a critical mass of people have the training to provide this test.

Why do women in Canada and other countries dislike SIPS/IPS?

Time and honesty. IPS requires you to have an ultrasound at about 12 weeks, and the answer is not told to you, until you complete your second portion 4-6 weeks later. If there is a problem, expectant mothers want to know sooner than later. Waiting until the second trimester is often very stressful for women, and creates anxiety and uncertainty.

Why do health practitioners dislike SIPS/IPS?

Practitioners too like to know sooner than later. As well, IPS presents an ethical dilemma, because medical information is withheld from ;them and ;their patients, which could make a difference in pregnancy management if known sooner. As well, patients and care givers, like the idea of a single early process for screening which SIPS, and IPS does not offer.

Is Quad or SIPS or IPS better than FTS?

In the case of Down syndrome screening, Quad performs at a 75% detection rate, with a 5% false positive rate. SIPS performs at 82% detection rate, and IPS detection is 88-90% detection rate with a 3-5% false positive rate.

The issue of False Negatives?

Statistics can sometimes be very difficult to interpret. A false negative is the chance that your screening test, will fail to detect the condition when present. False Negative rates are as follows:

  • Quad – 25% of patients with affected pregnancies will be missed
  • SIPS – 18-20% of patients with affected pregnancies will be missed
  • IPS – 10-12% of patients with affected pregnancies will be missed
  • FTS – 5% of patients with affected pregnancies will be missed

At the end of the day, without any screening, you likely have a healthy pregnancy; the vast majority of women that have screening find reassurance. We hope that you are able to fully enjoy the state of being pregnant, which is a profound and life changing experience. We also hope that this screening confusion does not cause anxiety. If we can be of any help in sifting through any of the options please do not hesitate to contact us, that’s what PCRM is here for.

Back to Resources