Role of saline infusion sonography in uterine evaluation before frozen embryo transfer cycle.

OBJECTIVE

To determine the role of saline infusion sonography (SIS) in uterine evaluation before a frozen embryo transfer (FET) cycle.

DESIGN

Retrospective cohort analysis.

SETTING

University hospital.

PATIENT(S): Thirty-six patients who had uterine evaluation by SIS before FET cycle.

INTERVENTION(S): The SIS was performed in the follicular phase of the menstrual cycle before the actual FET cycle.

MAIN OUTCOME MEASURE(S): The SIS findings, clinical pregnancy rate (PR), ongoing PR, and correlation between positive SIS findings with and without subsequent treatment and pregnancy outcome.

RESULT(S): Positive SIS findings were found in 11/36 patients (30.5%), which included uterine septum (9.0%), endometrial polyp (45.4%), intramural fibroid with normal cavity (9.0%), cystic endometrial changes (9.0%), cervical stenosis (18.1%), and calcification with normal cavity (9.0%). The overall clinical PR in all groups was 51.4%, with an ongoing PR of 45.7%. Patients with positive SIS finding who underwent subsequent hysteroscopic correction (7/11) had a clinical PR of 85.7% as compared to 54.1% in patients with normal uterine cavity (24/35). Patients with positive SIS findings and no operative hysteroscopy (4/11) had a clinical PR of 50% and pregnancy loss rate of 100%.

CONCLUSION(S): Obtaining an SIS before the FET cycle can be helpful in the detection of uterine abnormalities. If time since uterine evaluation has been more than 1-2 years, performing an SIS is recommended as subsequent correction of the anomalies may improve FET outcome.