Clarifying the relationship between total motile sperm counts and intrauterine insemination pregnancy rates.

OBJECTIVE: To study the relationship between postwash total motile sperm count (TMSC) and intrauterine insemination (IUI) outcomes. DESIGN: Retrospective review SETTING: Large fertility clinic PATIENT(S): A total of 92,471 insemination cycles from 37,553 patients were included in this study. INTERVENTION(S): All stimulated clomiphene citrate, letrozole, and/or injectable gonadotropin IUI cycles performed at a single institution from 2002 through 2018 were reviewed. Generalized estimating equations (GEE) analysis was used to account for multiple cycles by individual patients and to adjust for female partner age, body mass index, and stimulation protocol. MAIN OUTCOME MEASURE(S): Successful clinical pregnancy was defined as ultrasound confirmation of an intrauterine gestational sac with fetal cardiac activity. RESULT(S): A total of 92,471 insemination cycles were available to evaluate the relationship between postwash TMSC and clinical pregnancy. Pregnancy rates were highest with TMSC of ≥9 × 106 and declined gradually as TMSC decreased. Complete data for the adjusted GEE analysis were available for 62,758 cycles. Adjusted GEE analysis among cycles with TMSC of ≥9 × 106 (n = 46,557) confirmed that TMSC in this range was unrelated to pregnancy. Conversely, TMSC was highly predictive of pregnancy (Wald χ2 = 39.85) in adjusted GEE analysis among cycles with TMSC of <9 × 106 (n = 16,201), with a statistically significant decline. CONCLUSIONS: IUI pregnancy is optimized with TMSC of ≥9 × 106, below which the rates gradually decline. Although rare, pregnancies were achieved with TMSC of <0.25 × 106. Since the decline in pregnancy is gradual and continuous, there is no specific threshold above which IUI should be recommended. Rather, these more specific quantitative predictions can be used to provide personalized counseling and guide clinical decision making.

Robotic-assisted vasovasostomy: a two-layer technique in an animal model.

OBJECTIVES: To assess the feasibility of a multilayered robotic-assisted vasovasostomy (RAVV) in a rabbit model. Microscope-assisted vasovasostomy (MAVV) is a technically challenging procedure. Robotics may be a surgical adjunct that helps overcome the microsurgical challenges, which include fine suture, delicate instruments, and tremor. A recent survey revealed that most urologists use a multilayered technique for vasovasostomies. METHODS: A surgeon performed eight vasovasostomies with 10-0 suture and a two-layer technique using an in vivo rabbit model-four were MAVV using conventional microsurgical instrumentation and four were RAVV using the da Vinci robot. Performance measures and adverse haptic events were recorded. Patency was evaluated by passing a 2-0 Prolene suture through the anastomoses. RESULTS: The mean operating time for the total procedure and for the mucosal layer only was longer for RAVV than for MAVV (75 versus 42 minutes, P = 0.03 and 38 versus 23 minutes, P = 0.03, respectively). The needle passes required for the mucosal layer and the number of mucosal and muscularis sutures were similar in both groups (9.5 versus 8.8 passes, P = 0.34; 4 versus 4, P >0.99; and 7 versus 6.3, P = 0.2, respectively). Unlike MAVV, no tremor was appreciated during RAVV. No adverse haptic events were observed in either group. All anastomoses were patent, and all rabbits were free of any crush injury. CONCLUSIONS: A multilayered RAVV can be performed in an in vivo rabbit model. Although it was associated with increased operative times, the absence of adverse haptic events and comparable patency rates continue to suggest a role for robotics in microsurgery.

Initial evaluation of robotic technology for microsurgical vasovasostomy.

PURPOSE: Conventional microscope assisted vasovasostomy (MAVV) is a technically difficult procedure that is most successful in the hands of well-trained microsurgeons. Robotics may help surgeons overcome the microsurgical challenges of tremor, limited dexterity, miniaturized instrumentation and use of fine suture. We determine the feasibility of a robotic assisted vasovasostomy (RAVV) and compare performance measures with those of conventional MAVV. MATERIALS AND METHODS: One surgeon performed 10 vasovasostomies with a modified 1-layer technique and 9-zero suture on fresh human vas specimens using the robot in 5 RAVV cases and standard microsurgical instrumentation in 5 MAVV cases. Pre-specified performance measures and adverse haptic events (broken sutures, bent needles or loose stitches) were recorded. Patency was evaluated by instilling saline through the anastomoses. RESULTS: Mean operating time and number of adverse haptic events were higher for RAVV than for MAVV (84 vs 38 minutes, p = 0.01; 2.4 vs 0.0 events, p = 0.03). The number of needle passes required for the 6 full-thickness stitches was similar in both groups (16.8 vs 15.2 passes, p = 0.55). Although no tremor occurred during RAVV, minimal to moderate amounts occurred during MAVV. Minimal fatigue was noted for both groups. Patency was confirmed in all 10 operations. CONCLUSIONS: Use of RAVV in this human ex vivo vas model was feasible. While RAVV took longer to perform and was associated with adverse haptic events, elimination of tremor and comparable patency rates suggest that it may be a viable surgical alternative for microsurgical vasovasostomy.