My period is 4 days early

Patient: I have been on birth control for almost 3 years. Recently the maker of my generic birth control stopped and I went from Microgestin Fe 1/20 to Gildess FE 1/20. The pharmacy told me it was the exact same dosage. I am now getting my period symptoms 4 days early and still while on my active pills. I have not missed a dose I take it at the exact same time everyday, and I’m confused about what’s going on. I am also not sexually active.

Symptoms: Early Period

Doctor: Hi,Thanks for the query.I understand your concern.Both Microgestin Fe 1/20 and Gildess FE 1/20 contains Norethin done acetate 1mg and ethinyl estradiol 0.02mg.So, possibly the gonadal hormones should be maintained at same level with both tablets.But sometimes other ingredients of the tablets also can alter the symptoms like Gildess FE 1/20 contains ferrous fumarate in addition.Apart from this, lifestyle modifications, thyroid like hormonal fluctuations etc can affect the function of pills.Possibly in few months your cycles and premenstrual symptoms may get regularize.Take care.