The most common complication for patients is moderate or severe ovarian hyperstimulation syndrome (OHSS), which develops mainly due to hyperstimulation of the ovaries caused by fertility drugs. Hospitalization is the second common complication. The incidence of OHSS can be up to 153.5 (95% confidence interval [CI],146.0-161.3) per 10,000 autologous oocytes (women using their own oocytes rather than donor donor eggs) and up to 34.8 (95% CI, 30.9-39.3) for hospitalization. In contrast, the incidence of other complications was very low, less than 10/10,000 during the entire treatment cycle, all of which included infections, hemorrhage, adverse drug reactions, anesthetic complications, and death during the 12 weeks of receiving drug stimulation. In recent years, egg retrieval has shifted from laparoscopy to non-surgical, less invasive transvaginal retrieval, and earlier studies have shown that this shift has improved the overall pregnancy probability. The focus of this new study, however, is not on pregnancy rates, but rather on the post-treatment benefits for infertile patients. “To our knowledge, this study is the first to quantify patient risk associated with ART technology in the United States,” the authors said. The study also looked at adverse events with oocyte donation assisted reproductive technology and found that the risk was even lower than with autologous oocytes. The P value for complications with oocyte donation assisted reproductive technology was less than 0.05, with OHSS (peak of 31 per 10,000) and hospitalization (10.5 per 10,000) also being the most common complications. OHSS was the most common complication in the ART technique, so the authors suggest that in the future they would like to see more studies looking at the predictors of OHSS.