by Shannon Bartlett
You've been in for your first prenatal visit and maybe had an ultrasound to confirm your dates. Next you'll be offered a first trimester screening. This noninvasive evaluation combines results from an ultrasound of your baby and a maternal blood test.
The blood screen: A finger stick blood test measures two pregnancy related hormones: free beta-human chorionic gonadotropin, hCG and pregnancy associated plasma protein-A, PAPP-A.
The nuchal translucency ultrasound takes between 20 and 40 minutes. This scan measures the clear space beneath the skin behind your baby's neck, called the nuchal translucency or NT, a sign of Down syndrome, trisomy 18 or trisomy 13. Babies with an extra chromosome can have more fluid at the base of their necks. The sonogram also checks to see if your baby's nasal bone is present or absent
Age and dates: Combining your age-related risk with the NT measurement, nasal bone information, and blood work provides you with one risk figure for Down syndrome and one risk figure for trisomy 13 or trisomy 18.
Schedule this ultrasound for between 11 weeks 4 days and 14 weeks 3 days of your pregnancy. The timing is important because as your baby grows, the nuchal fold becomes less transparent and the amount of fluid difficult to measure.
Your ultrasound appointment will probably be the standard where you're asked to drink a lot of water and the technician squeezes gel on your abdomen and uses a probe to "look" at your baby.
In addition to measuring the nuchal translucency, the technician might count babies (you were hoping for twins, right?) and check your dates.
Drink two 8-ounce glasses of non-carbonated fluid an hour before your exam. Don't use the bathroom until after your scan. A full bladder helps the ultrasound produce better images.
Schedule your next prenatal visit, if you haven't already. Unless you're experiencing a high risk pregnancy, your midwife or doctor will probably want to see you about four weeks after your first prenatal appointment.
At this visit, you can go over the first trimester screening results and discuss additional testing option such as chorionic villus sampling and amniocentesis, either with your provider or with a genetic counselor.
Visit with your baby. During today's ultrasounds, you'll have a chance to see your baby's heartbeat. If your baby bean's awake, you might see kicks and wiggles. Did you have a dating ultrasound? Your baby's grown! It seems like every day brings a change.
You're free to ask about anything but your technician will probably have you check in with your healthcare provider for the answers. It doesn't mean anything's wrong; so jot those questions down and give your midwife or doctor a call.
We've tapped our members to see what questions popped up about their first trimester screening. They wanted to know the following: