Kapag ba 8 weeks and 3 days possible pa din na hindi ma detect yung heart beat ni baby ?

nagpa TVS ako at 10weeks based sa lmp pero 7weeks pa lang sa tvs. kita na si baby with cardiac activity. so may 3 weeks difference sakin. so for 8 weeks based from lmp at no heartbeat, maaaring too early pa. no heartbeat kapag not visible pa si baby. kaya repeat tvs after 2 weeks.