Irregular periods often indicate irregular ovulation, which is a very common and highly treatable cause of difficulty conceiving. Depending on the underlying cause, a doctor may prescribe generic medications like letrozole or clomiphene citrate to help stimulate ovulation and improve fertility. If insulin resistance (often associated with PCOS) is present, metformin can help regulate your cycle. Sometimes, progesterone is prescribed to establish regular bleeding. I highly recommend consulting an OB-GYN or fertility specialist first. They can perform simple hormone tests and ultrasounds to identify the exact cause and safely prescribe the correct treatment for you. There are many highly effective options available.