Incidence and Recurrence of Uterine Polyps in Women Undergoing Embryo Transfer

To determine how often saline infusion sonohysterography (SIS) should be repeated in women preparing to undergo embryo transfer (ET). IRB approved retrospective study at an academic fertility center. Medical records of 194 women undergoing SIS in preparation for ET on two or more occasions from 2008-2013 were reviewed. During that time, according to the policy at our center, SIS was performed within 6 months before every embryo transfer, even if a prior SIS was normal. The incidence of an abnormal SIS during the first study was the primary outcome studied. Secondary outcomes included the incidence of an abnormal SIS in a subsequent study if initial SIS is normal, and incidence of an abnormal SIS in a subsequent study if the initial SIS is abnormal. Descriptive statistics were used to evaluate the data. The initial SIS was abnormal in 35 of 194 women (18%), and 33/35 underwent a corrective hysteroscopy. Endometrial polyps were the most common uterine abnormality, and polyps were confirmed by pathology in 60.6% of all hysteroscopies. A second SIS was performed in 82 women. Of 64 with a normal initial SIS, 57 (89%) remained normal and 7 (11%) became abnormal. Of 18 who had an abnormal initial SIS, 15 (83%) were normal and 3 (17%) were again abnormal during the second SIS. Approximately 20% of women were abnormal at both 6 and 12 months. As expected, women with an abnormal SIS result had significantly more days of menstrual bleeding than those with a normal SIS (mean 5.2 vs. 4.7, p=0.02). Peak endometrial thickness was significantly greater in women with an abnormal SIS than in those with a normal SIS (p=0.02). The live birth rate were significantly higher in patients with a normal SIS compared to those with an abnormal SIS, even after correction (p=0.04). None of the other variables examined were significantly different between the two groups. The optimal time to repeat endometrial assessment in women preparing for assisted reproduction procedures has not been established, and there is very little evidence in the literature to provide guidance. The incidence of uterine abnormalities is high in infertile women undergoing assisted reproduction procedures. Endometrial polyps may reduce endometrial receptivity (1), and hysteroscopic removal is recommended for infertile patients undergoing IVF (2). Our data supports the policy of performing or updating the SIS within 6 months in order to identify and correct uterine abnormalities before performing an embryo transfer.