Ultrasound is the most versatile method for pre-treatment assessment in IVF being the dominant instrument for assessing ovarian reserve, pelvic pathologies and for assessing the uterine cavity. The ability of ultrasonography to measure endometrial thickness in addition to detecting uterine masses gives it an edge over laparoscopy/hysteroscopy as a diagnostic procedure in uterine cavity assessment, although hysteroscopy has the advantage of therapeutic potential. Similarly, ultrasonography is superior to biochemical methods for follicular monitoring because of its ability to demonstrate the number and sizes of follicles, and guide preparations for oocyte retrieval. The relative ease of ultrasound guided oocyte retrieval; its less technical demands and the possibility of conducting the procedure under local anaesthesia have made ultrasound guided oocyte retrieval more popular across the world. Randomized controlled trials show that ultrasound-guided transfer techniques have better outcomes than the clinical touch technique in terms of on-going pregnancies and Clinical pregnancies. Ultrasonography is now the key instrument for diagnosing and monitoring pregnancy following embryo transfer, biochemical methods being complimentary.