Here is an article on this subject:
Any woman who goes to her doctor with a complaint about her menstrual cycles is likely to walk out with a prescription for the birth control pill. The pill has become the mainstay of reproductive medicine and is prescribed for everything from acne to infertility as well as being commonly used to manage the symptoms of more serious conditions like endometriosis and polycystic ovarian syndrome (PCOS).
And it is not hard to find a Catholics (including priests and apologists) who maintain that taking the birth control pill to treat a medical condition is morally acceptable even for a married woman because the intention in doing so is not to contracept, but to alleviate the symptoms from which the woman is suffering. And this is true up to a point. As explained by Pope Paul VI in Humanae Vitae, a contraceptive effect (an “impediment to procreation”) is usually morally permissible as a side effect of treating a medical condition:
â€œOn the other hand, the Church does not consider at all illicit the use of those therapeutic means necessary to cure bodily diseases, even if a foreseeable impediment to procreation should result there fromâ€”provided such impediment is not directly intended for any motive whatsoever.â€