What is the best time for prenatal diagnosis?
If mutations are identified in the previous affected child as both the partners (husband and wife), prenatal diagnosis is done on CVS sample at 12-14 weeks of pregnancy. The known mutations are checked in the CVS sample. If one or both mutations are unidentified, the options include linkage analysis, globin chain synthesis studies or cord blood HPLC. The legal limit for termination of pregnancy as per MTP Act is 20 weeks. Therefore, one should try to give a diagnosis before 20 weeks. At present, many couples come late in pregnancy, so it is necessary to increase awareness to enable early prenatal diagnosis and effective prevention.
