It could be a tubal contraction that is felt sometimes after ovulation as the fibroids have been concluded to be small enough not to bother the uterine frame work. Fibroids that are located just below the outer surface of the uterus
or the subserous ones, do not pose any serious problem in conception and the ongoing pregnancy
, while those located just beneath the inner lining or submucous type or those in the muscle or intramural type, can create difficulty in conception or continuation of pregnancy. Hope this helps.