Is it necessary to terminate pregnancy based on test results?

No. What test results? Terminating pregnancy is a very personal issue and this is not a proper forum for such an issue.
No. Ending a pregnancy is always your decision. A test result can influence that decision but it doesn't make it for you. Take into consideration the problem that the test found. How would it impact your family? How would it impact your child? Ultimately, you decide if the abnormality is not something you can put yourself, your family or your child through.