Understanding Down Syndrome Screening: What You Need to Know

Question
Hi Doc. I am 27 and this is my fourth child,my due date is 8/7/06. My ob's nurse called me this morning and informed me, i had abnormal results on my maternal serum screening. She told me I needed to see a specialist first thing in the morning. She wouldn't give me any details but she did say something about the possibility of down syndrome. Doc i am freaking out and scared to death, please give me some info on this screening test and...i just want to know something about this, I'm losing it here.      Thank you  

Answer
The alphafetoprotein screen  is performed to see if there is a higher risk of neural tube defects (spina bifida, anencefaly) or Down Syndrome. If the AFP is elevated, it can be due to neural tube defects, or twin gestation. If the AFP is lower than usual, it may be normal or due to Down Syndrome. If we suspect that it may be due to Down syndrome, we suggest amniocentesis to the patient. That is the only definitive test. A little fluid is taken from around the baby and grown on a plate so that a karyotype is produced. All of your chromosomes can be seen and we can immediately tell if you have trisomy 21 (Down Syndrome) or not. Discuss it with the doctor.