Medication-Induced Oligomenorrhea
Some medications would have a significant effect on the menstrual cycle. These include Depo-Provera shots, birth control pills, inserted IUD, or using a ring or a patch. In certain women, periods would become heavier and more frequent. However, you would have the infrequent, light periods when oligomenorrhea occurs. Those who often change methods or take birth control irregularly would also experience unpredictable or abnormal bleeding. Symptoms tend to improve when you use a suitable medication consistently. Other drugs that would increase the risk of oligomenorrhea include antipsychotic or anti-anxiety drugs, epilepsy medications, as well as anticoagulants like aspirin. [5]
