Expert: Sarah Conlon - 7/18/2008

Question
Hello.  I usually detect my LH surge (according to OPK) day 17-19.  This cycle, I have begun having u/s to monitor follicle size.  On day 10, there were several follicles, the largest being 9mm on the right.  At day 12, the largest was a follicle from the left at about 10mm.  At day 17, largest is on left at 14mm.  I understand that follicles should be >20mm for ovulation to occur.  Is it possible for ovulation to occur with follicles <20?  Is it possible to have an LH surge with no ovulation?  I guess I'm just wondering if this means I'm not going to ovulate this month, and if it is possible that I have not been ovulating when I thought I was?  Thanks for your help!

Answer
Hi Michele,

It is possible to have ovulation with follicles at least 18 mm.  It is also possile, although somewhat rare to have a positive LH surge without actually ovulating. You will probably ovulate, as your follicles are maturing, but not for another couple of days. They usualy grow 1 or 2 mm per day.  Good luck.