ad. 8. When should I undergo a biochemical test in the first trimester (PAPP-A and fβ-HCG test)?
When the specialist in charge recommends a biochemical examination along with an ultrasound scan in the first trimester, the best time for the examination, in respect of its sensitivity, would be around 10 weeks of gestation (this is optimal timing for the key parameter- PAPP-A) . At 12 weeks the results are already available and they might be included into the genetic risk assessment at the same time as the ultrasound scan is performed. Such an approach reduces the number of appointments to the necessary minimum and it allows to interpret the patient’s blood test results together with the ultrasound scan.
We often encounter the screening model, in which first a patient undergoes an ultrasound examination and on the same day she has her blood sample taken for biochemical examination, and, as a consequence, she returns home without any initial results. Next, after a week the patient receives the examination report from the medical staff, without a specialist consultation and without the possibility to discuss the results. Thus, the patient frequently seeks help in interpretation of the results on her own. Undergoing a biochemical test at 10 weeks of gestation, and an ultrasound examination when the biochemical test results are already available would allow patients to avoid the situation described above and reduce stress during pregnancy at the same time.
If you have any recommendations, or you would like to include biochemical parameters into an aneuploidy risk assessment, please mention that information while scheduling the appointment. The reception desk will direct you to a laboratory accredited by the Fetal Medicine Foundation.