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What is A G3P2, pregnant comes to your clinic at 18 weeks of gestation for genetic counselling. She has a history of two kids born with thalassemia major. Which test would you recommend now? and explain in detail?
Ans: C. Cordocentesis(Ref Williams 24/e p300; (Thai 8/e p341-344)Recommended test - Cordocentesis.As patient is presenting at 18 weeks - Quick method diagnosing thalassemia antenatally needed.Note:Legal age of aboion is only till 20 weeks.Fetal blood karyotyping accomplished within 24 to 48 hours.Significantly quicker than (7- to 10-day turnaround time with amniocentesis or CVS).