<prompt> The commonest cause of primary Amenorrhoea is:Genital tuberculosisOvarian dysgenesisMullerian duct anomaliesHypothyroidism  <response>: Most common cause of Primary Amenorrhea Gonadal dysgenesisovarian dysgenesis2nd most common cause of Primary Amenorrhea Mullerian agenesis Mayer Rokitansky Kuster Hauser Syndrome Mullerian agenesis is a relatively common cause of primary amenorrhea, more frequent than congenital androgen insensitivity and second only to gonadal dysgenesis 3rd most common cause is testicular feminizing syndrome. 