In vitro fertilization outcomes with direct aspiration with single-lumen needles compared to follicular flushing with double-lumen needles for oocyte retrieval in poor responders

Abstract

To identify the impact of using single-lumen vs double-lumen needles with follicular flushing during oocyte retrieval in poor responders undergoing in vitro fertilization (IVF). Our hypothesis was that the use of double-lumen needles with follicular flushing would improve oocyte yield and IVF outcomes. Retrospective cohort study of IVF cycles with 7 or fewer follicles >10mm at time of hCG administration. A total of 132 IVF cycles had ≤7 follicles measuring >10mm at time of hCG administration. Of these, 93 underwent retrieval with a single-lumen needle and 39 with a double-lumen needle with utilization of follicular flushing. Cycle characteristics of the two groups were collected and compared. All cycles underwent fresh embryo transfers three or five days post oocyte retrieval without preimplantation genetic testing. Oocyte number, mature oocyte number, procedure time, fertilization rate, pregnancy rate, implantation rate, clinical pregnancy rate, and live birth rate were assessed for each group. A subgroup analysis was also conducted on cycles with ≤ 5 follicles at time of hCG administration. Statistical analysis was performed using Student’s t-test, Chi-square, or Fisher’s exact test. When compared to the single-lumen cohort, the double-lumen cohort had a statistically significant fewer number of oocytes retrieved (5.26 vs 7.11, p <0.001), fewer mature oocytes (4.59 vs 6.0, p 0.001), increased procedural time (24.15 vs 9.41, p <0.001), and fewer 2pn embryos observed (3.15 vs 3.94, p 0.03). There was no difference in the number of embryos transferred. Cycles with single-lumen retrieval had statistically significant higher positive pregnancy rate (55.91% vs 28.21%, p 0.004), implantation rate (27.67% vs 16.25%, p 0.044), and clinical pregnancy rate (45.16% vs 25.64%, p 0.036). The live birth rate was also higher in the single-lumen group but did not reach statistical significance (40.86% vs 25.64%; p 0.097). Subgroup analysis of cycles with ≤ 5 follicles at time of hCG administration showed similar results in respect to number of oocytes retrieved, number of mature oocytes, procedural time, and number of 2pn embryos observed. There was no difference in any of the pregnancy outcomes in those cycles with ≤ 5 follicles at time of hCG administration. Our results suggest that there is no improvement in IVF outcomes with the use of a double-lumen needle with follicular flushing compared to the use of a single-lumen needle in poor responders. We found that the use of a double-lumen needle with follicular flushing not only increased the procedural time but had a negative impact on the number and quality of oocytes retrieved, implantation and clinical pregnancy rates when compared to retrieval with a single-lumen needle.