Ovarian follicular flushing among low-responding patients undergoing assisted reproductive technology. A prospective randomized study comparing aspiration only with aspiration and flushing for transvaginal ultrasound-directed oocyte recovery. A prospective randomized comparison of single- and double-lumen needles for transvaginal follicular aspiration. Is follicular flushing necessary for oocyte retrieval? A randomized trial.
A randomized comparison trial was performed to evaluate whether follicular reaspiration with use of a double-lumen retrieval needle improves oocyte recovery when compared with direct follicular aspiration among low-responding patients undergoing ART. There were no differences observed in the number of oocytes retrieved (single lumen: 6.5 +/- 2.2 oocytes, double lumen: 7.2 +/- 2.3 oocytes) whereas follicular reaspiration with the double-lumen retrieval needle resulted in a twofold increase in procedure time. To compare aspiration only with aspiration and flushing of ovarian follicles during transvaginal ultrasound (US)-directed oocyte recovery.
                Prospective randomized study.
                One hundred patients who were undergoing an in vitro fertilization (IVF) treatment cycle.
                All patients underwent pituitary desensitization before the administration of gonadotropins. Monitoring of ovarian stimulation and the criteria for the administration of human chorionic gonadotropin were similar in both groups. In patients in whom aspiration alone was used, each follicle was aspirated until it was empty. The US probe was then rotated until every drop of follicular fluid had been aspirated before the next follicle was aspirated and the procedure repeated. For patients who had aspiration and flushing, each follicle was aspirated and then flushed up to a maximum of six times before moving to the next follicle. In both groups, all follicles greater than 10 mm were aspirated.
                The indication for IVF and mean age of the patients were comparable in the two groups. There were no significant differences between the aspiration and the aspiration and flushing groups in terms of the number of oocytes retrieved (11 versus 9), the oocyte recovery rates (77.5% versus 77.0%), the fertilization rates (55.6% versus 60.0%), the number of embryos transferred (2 versus 2), or the number of clinical pregnancies (12 versus 13). The time taken for oocyte recovery was significantly shorter (15 versus 30 minutes, P less than 0.00001), and the dose of pethidine required significantly less (50 mg versus 100 mg, P less than 0.00001) in the aspiration only group.
                Aspiration alone produces comparable oocyte recovery rates as aspiration and flushing while significantly reducing the length of the procedure and the dose of analgesia required. Aspiration alone suffices for virtually all cases during transvaginal US-directed oocyte recovery. Patients undergoing ultrasound-directed transvaginal follicular aspiration in a large in vitro fertilization (IVF) program were randomized for retrieval with either a single-lumen needle (SLN; N = 22) or a double-lumen needle (DLN; N = 22) to compare recovery rates and the technical aspects of their use. Two hundred ten and two hundred two follicles were aspirated with each needle, respectively. Follicular diameters were measured ultrasonically at the time of aspiration and recorded. One or more washes were performed when using the DLN and the SLN was withdrawn each time to recover the fluid in the dead space of the needle. The distribution of follicular sizes was the same for both needles. Oocyte recovery rates (SLN = 65.7%; DLN = 63.9%) and the incidence of fractured zonae (SLN = 9.1%; DLN = 6.4%) were the same for both needles (alpha greater than 0.50; beta less than 0.01). Although there were no differences between the two needles in the number of oocytes provided for IVF, there were technical differences. The DLN needle was more flexible and frequently deviated from the projected path as observed by ultrasound. The SLN may be preferable because it is technically easier to use; however, there may remain specific indications for the use of the DLN. A prospective randomized trial was performed to evaluate the necessity of follicular flushing during transvaginal, ultrasonically guided oocyte recovery under mild sedation. Patients with tubal damage as the sole cause of their infertility were randomized into one of two groups. Group one had their follicles aspirated only. Follicles of patients in Group 2 were aspirated and flushed with a total of 10 ml of flushing medium. There was no significant difference in the number of oocytes retrieved, fertilization rate or pregnancy rate in each group. There was, however, a significant shortening of operating time in the aspiration only group.
There is no evidence that follicular aspiration and flushing is associated with improved clinical or ongoing pregnancy rates, nor an increase in oocyte yield. The operative time is significantly longer and more opiate analgesia is required for pain relief during oocyte retrieval. There is a lack of evidence regarding the effect of follicular aspiration and flushing on live birth rates in the identified data.