What must be done following an abnormal FISH result?

Following an abnormal FISH (Fluorescence In Situ Hybridization) result, confirmatory testing is necessary to ensure the accuracy of the initial findings. FISH is a molecular cytogenetic technique used to identify specific DNA sequences or chromosomal abnormalities within cells. While an abnormal result may indicate a potential genetic disorder or aneuploidy, it is essential to confirm these findings to rule out false positives or testing errors.

Confirmatory testing might include additional methods such as karyotyping or more extensive genetic testing, which provide further insight into the chromosomal makeup of the fetus. This process is critical in making informed clinical decisions regarding the management of the pregnancy and counseling for the parents.

Moving on to other options, immediate termination may be considered in cases of lethal anomalies, but it is not a blanket recommendation following any abnormal FISH result. The option stating that no further testing is required undermines the importance of confirming the initial findings, potentially leading to misinformation. Finally, merely repeating the FISH test without further assessment does not address the need for validation of the abnormal results and could lead to unnecessary anxiety or mismanagement. Hence, the appropriate course of action is to pursue confirmatory testing to clarify the situation.