Can I Take Duphaston For Missing Periods?

Hi Doctor,

mt periods are usualy regular but last month i missed it. Had bad stomach and back ache but now its gone. i usually get my periods every month between 12th - 16th.

i am not married and could not be pregnant also.

From past 2 years there is always a month in which i miss my period and i am given Duphaston for 5 to 7 days.

Can i take that now? if so how should i take it? I am also diagnosed with PCOS, and recently i have gained weight also. Like in last 1 year around 8 to 10kgs. My current weigh is 70kgs. i feel really bloated due to of missing a period.

Please suggest what i should do.