Effect of Follicular Flushing During Oocyte Retrieval on Clinical Outcome of Assisted Reproductive Technology

Abstract

Assisted reproductive techniques are an accepted form of treatment for infertility and the procedures used are generally assumed to be relatively constant in the way they are performed between centers. Transvaginal ultrasound guided oocyte collection is now almost universal (Scott et al., 2001). In early stages of assisted reproductive technologies (ART), oocyte retrieval was performed via laparoscopy, a cumbersome and expensive process requiring general anesthesia (Lenz et al., 2001). Today, transvaginal oocyte retrieval for ART is a routine procedure performed under ultrasound guidance. Double lumen retrieval needles, which are capable of flushing ovarian follicles, were developed to overcome the possibility of oocyte retention within the ovarian follicles and retrieval collection system (Knight et al., 2001). The place of follicular flushing during oocyte recovery in ART is still uncertain. The pros of flushing include the possibility of obtaining more oocytes, and subsequently more embryos. Whether this translates into a higher pregnancy rate and live births remains unknown. The cons of flushing are a longer operative time and larger amounts of required anaesthetics and analgesics. From a patient’s perspective, it could also mean higher costs. The objective of the study was to evaluate the effect of follicular flushing on IVF cycle outcomes, including the number of oocytes retrieved, number of mature oocytes, fertilization rate, number of embryos transferred, implantation rate, operating room time, pregnancy rate and post operative adverse event. The study was a prospective randomized controlled trial. 190 (complete outcome data were available in 185 (97%) infertile women who underwent IVF/ICSI were included in the study after verbal and written consent. They were recruited from Assisted Reproductive Technology unit, Ain Shams University maternity Hospital during the period from September 2011 to September 2013. The total sample size was calculated as 190 cases, randomized using a block randomization method on the day of oocyte retrieval into two equal groups: • Group 1: this group consisted of 95 (93 completed the study) cases underwent aspiration alone during oocyte retrieval. • Group 2: this group consisted of 95 (92 completed the study) cases underwent aspiration and flushing during oocyte retrieval. Patients meeting study requirements were offered enrollment. Each patient in the study and control groups subjected to the following: - Controlled ovarian hyperstimulation using down regulation with GnRH analogue in mid-luteal phase of pretreatment cycle as the standard protocol with Triptorelin acetate (Decapeptyl) 0.1 mg subcutaneous at day 14 to 16 of pre-induction cycle, followed by ovarian stimulation with HMG (human menopausal gonadotropin) at day 3, dosage of HMG depends on the BMI, age, FSH, and ovarian size by TVUS, At the first scan, the number, sizes of the follicles were written. If he size is 12-14 mm allowed two days before next scan, if 14 mm or more next scan was within 24 hours , human chorionic gonadotropin (choriomon 5000iu, IM injection) administrated 10000 iu when three or more follicles were at least 18 mm in largest diameter, Trans-vaginal follicular aspiration performed 34-36 hours after hCG trigger as the following: - During the trial period the following parameters kept constant, The manufacturer of the aspiration needles (Wallace Oocyte Recovery Systems; Oocyte Recovery Needle 33cm x 16), the pump (Pioneer Pro-pump, GenX International; Guilford, CT) and pressure used set to maximum of 120 mmHg at aspiration, and up to 200 mmHg at re-aspiration in flushing group, staff involved in all set procedures, the premises and equipment at oocyte collection and culture. In the aspiration alone group, a 16 gauge single lumen needle used, with suction continue until a small amount of blood stained fluid appeared in the tubing or flow stop. The dead space within the needle and tubing suctioned upon removal from the vagina. When flushing accompany aspiration of follicular fluid in the study group, the same needle used with a double-way tap allowing the same amount of culture medium as the follicle volume to be circulated through the empty follicle (2 ml) of Earl's medium till oocyte retrieved or maximum two times. The embryologist identifying and collecting the oocytes remained blinded to the group assignments. The providers performing the oocyte retrieval remained blinded to the number of oocytes retrieved until the completion of the procedure. The patient kept under observation for two hours to assess presence of adverse events, including complication rate for the surgical procedure and during the flushing procedure (post operative pain (need for diclphen 75 mg im vial, internal hemorrhage, infection, vomiting and hypotension). Secondary end-points included recovery rate, total number of mature oocytes, maturity rate, fertilization rate, number of embryos transferred, implantation rate, on-going pregnancy rate. Embryo transfer for both groups done in the morning of day 3 using (Labotect catheter, Germany) while the patient in Lithotomy position and semi-full bladder, patients instructed to be resting on their back for at least 30 minute following the process of embryo transfer.Patients start progesterone medication after oocyte retrieval. All cases will underwent an initial serum test for B-HCG two weeks after embryo transfer, chemical pregnancy is defined when level of B-HCG is higher than 25 iu, while clinical pregnancy is defined when fetal heart pulsation could be detected from 6 to 7 weeks by TVUS.