Do Althea Pills Affect The Menstrual Cycle?

my OB found out that I have endomentrial cyst on my left ovary 4cm. That is why I undergo for laparoscopy operation. Now, already removed my cyst. I prepare myself, because my husband work in other country and he will be back this coming Sept. and we are planning to have a baby.My OB advise to take althea pills. I'll started to take this last jun. 25 onwards. It is ok to take althea pills straightly until sept? im just worried because my menstruation period is regularly, It can effect my cycle? pls. advise. Im 30yrs. old height 4"11 with weight 55kgs. I'll found out that I have endomentrial cyst last Jul. 2010.