Irreular period problem. My pregnancy.

I had first episode of irregularity of period in feb . My last period was on 19 jan . Feb last I took meparate and 10 march I got periods . In april month Since I dont want to take medicines , I did some blood test - sugar thyroid prolactin . Sugar thyroid is normal , prolactin is 49 . I dont have any breast discharge . I am 37 year old . I have 2 year old daughter . Upt is negative . Anyhow we are not planning any pregnancy in future . I assume high prolactin is the cause for irregularity . I just wanted to take the opinion of renowned doctors here that what is the line of treatment now . Any medication . And also kindly note that I have pms symptoms from last 5 days . But periods are not coming . I assume prolactin level should be controlled . Is ultrasound necessary . I dont have any pcod , pcos history .I conceived naturally during my pregnancy .