If You are Pregnant with Twins

If you are carrying a twin pregnancy, you can have OHIP-funded Non-invasive prenatal testing (NIPT), regardless of your age or other factors.  This testing can be organized by the doctor or nurse practitioner who is looking after your pregnancy.

There are two provincial laboratories that offer OHIP-funded NIPT (LifeLabs and Dynacare). NIPT can usually be ordered for twin pregnancies through either laboratory. However, there are two situations when NIPT should only be ordered through Dynacare:

1. a twin pregnancy where a donor egg was used.
2. a twin pregnancy where a gestational carrier (surrogate) is involved. 

It recommended that you also consider having a 11-14 week ultrasound, which may include the measurement of the Nuchal translucency (NT), if available in your area.

First Trimester Screening (FTS) is no longer offered as a prenatal genetic screen for twin pregnancies. If you already had FTS in your pregnancy, you are now eligible for OHIP-funded NIPT even if your FTS results were "screen negative" (low-risk). NIPT is a more accurate form of prenatal screening. We encourage you to speak to your doctor or nurse practitioner about this option.

If You are Pregnant with More than Two Babies

If you are having triplets, quadruplets, or more, your option for screening the pregnancy for chromosome differences is limited to:

• Nuchal translucency (NT) ultrasound only

The NT measurement may be combined with maternal (or egg donor) age to calculate the chance for each baby to have trisomy 21 (Down syndrome).

"Vanishing" Twin

A vanishing twin scenario occurs when a twin or fetus in a multiple pregnancy disappears during the pregnancy as the result of a miscarriage of one fetus. This fetal tissue is then absorbed by the other fetus, the placenta or the pregnant individual.

In the case of a vanishing twin, the recommended option for prenatal screening is:

• if there is access to NT ultrasound - nuchal translucency (NT) ultrasound with MSS bloodwork
• if there is no access to NT ultrasound – MSS bloodwork alone

If MSS blood work is drawn, it is recommended that it be drawn at least 8 weeks after the estimated time of miscarriage of the fetus.