In vitro fertilization (IVF) is expensive, time consuming, and the most successful treatment of fertility; however, in general the cumulative chance of having a live birth with the treatment is still around 40%. Many couples still remain unsuccessful after several IVF attempts, causing deep impact on quality of life, and each failed cycle causing a financial burden. Several adjuvant therapies have been used along with IVF to increase the pregnancy rates for women with repeated implantation failure. Testing of adjuvant therapies in properly conducted randomized controlled trials is rarely done so that potential benefits and risks are unlikely to be clearly presented to patients and clinicians. In this review, we assessed the effects of adjuvants, such as growth hormone, androgens, and glucocorticoids to enhance oocyte number and quality; sildenafil, low-dose aspirin, heparin, corticosteroids, granulocyte colony-stimulating factor, endometrial injury, intrauterine injection of human chorionic gonadotropin, and intrauterine administration of autologous peripheral blood mononuclear cells to improve poor endometrial response; antioxidants, complementary and alternative medicine modalities, such as Chinese herbal medicine and acupuncture; and assisted hatching and preimplantation genetic screening to correct embryonic factors.