The Mystery of Luteinized Unruptured Follicle Syndrome (LUF), NSAIDs . . . Since this is the basis for many forms of simple fertility therapy, the possibility of LUF is covered and post-trigger ultrasound monitoring is not necessary Of note, in vitro fertilization can, of course, overcome this problem as well NSAID use associated with luteinized unruptured follicle syndrome is likely not a major cause of infertility