Ultrasonography is an invaluable tool in the noninvasive assessment and monitoring of treatment in infertile women. Incidental adnexal pathology is identified in 5–18% of such women when using ultrasound (US). Transvaginal high-resolution ultrasonography in particular has gained widespread use in infertile women because of the detail that can be visualized when examining the pelvis and reproductive organs. Incidental adnexal masses may be seen when pelvic ultrasound or hysterosalpingo-contrast-ultrasonography (HyCoSy) is performed with the intention of evaluating uterine pathologies potentially associated with subfertility, such as adhesions, polyps, submucous leiomyomas, and septae . Adnexal pathology may also be seen when monitoring ovarian response to stimulation with gonadotropins or ovulation induction with clomiphene citrate, during oocyte retrieval, or at the time of US-guided embryo transfer. A functional ovarian cyst is also a relatively common finding with the widespread use of gonadotropin-releasing hormone (GnRH) agonists, which initially provoke an initial follicle-stimulating hormone (FSH) surge . In addition, women undergoing ovarian stimulation may present with acute pelvic pain because of ovarian hyperstimulation syndrome (OHSS), pelvic infection, or ovarian accident. In this chapter we will discuss a range of incidental adnexal findings in nonacute presentations, their significance for reproduction and assisted reproductive technologies (ART), and how to approach them once found.