Risk factors for multiple gestation in women undergoing intrauterine insemination with ovarian stimulation

Objective: To identify whether sperm characteristics after washing and/or ovulation induction cycle characteristics can predict the occurrence of multiple conception in patients undergoing ovarian stimulation and IUI. Design: Retrospective study. Setting: A gynecology clinic and an andrology laboratory at a tertiary care facility. Patient(s): One hundred patients with single pregnancies and 22 patients with multiple pregnancies. Intervention(s): Patients underwent ovarian stimulation and IUI with their partner's sperm. Main Outcome Measure(s): Relation of patient characteristics, ovarian stimulation, and sperm characteristics after washing to the occurrence of multiple pregnancy. Result(s): The mean serum E-2 level on the day of hCG injection was significantly higher in the multiple conception group, but the number of follicles was not. The total sperm count, total motile sperm count, and sperm motility after washing did not differ between the groups. However, couples with multiple pregnancies had sperm with a significantly higher amplitude of lateral head movement than couples with single pregnancies. A peak E-2 level of >583 pg/mL on the day of hCG injection and sperm with an ALH of >4 mu m after washing predicted the occurrence of multiple pregnancy. Conclusion(s): Sperm with an amplitude of lateral head movement of >4 mu m and a peak E-2 level of >583 pg/mL are significant risk factors for multiple pregnancy in patients undergoing IUI. (Fertil Steril(R) 1999;72: 613-8. (C) 1999 by American Society for Reproductive Medicine).