James Meriano

Coenzyme Q10 restores oocyte mitochondrial function and fertility during reproductive aging

Female reproductive capacity declines dramatically in the fourth decade of life as a result of an age‐related decrease in oocyte quality and quantity. The primary causes of reproductive aging and the molecular factors responsible for decreased oocyte quality remain elusive. Here, we show that aging of the female germ line is accompanied by mitochondrial dysfunction associated with decreased oxidative phosphorylation and reduced Adenosine tri‐phosphate (ATP) level. Diminished expression of the enzymes responsible for CoQ production, Pdss2 and Coq6, was observed in oocytes of older females in both mouse and human. The age‐related decline in oocyte quality and quantity could be reversed by the administration of CoQ10. Oocyte‐specific disruption of Pdss2 recapitulated many of the mitochondrial and reproductive phenotypes observed in the old females including reduced ATP production and increased meiotic spindle abnormalities, resulting in infertility. Ovarian reserve in the oocyte‐specific Pdss2‐deficient animals was diminished, leading to premature ovarian failure which could be prevented by maternal dietary administration of CoQ10. We conclude that impaired mitochondrial performance created by suboptimal CoQ10 availability can drive age‐associated oocyte deficits causing infertility.

The choice of embryo transfer catheter affects embryo implantation after IVF

OBJECTIVE Comparison of two transfer catheters in an IVF program. DESIGN Prospective, randomized clinical study. SETTING A private tertiary care center for ART. PATIENT(S) 66 patients < 38 years of age undergoing IVF and/or ICSI. INTERVENTION(S) Patients were randomly assigned to undergo ET using the Tomcat catheter (n = 32) or the TDT catheter (n = 34). MAIN OUTCOME MEASURE(S) Primary outcome measures were implantation and pregnancy rates. Secondary outcome measures were contamination with blood and/or mucus on the tip of the catheter, cramping or patient discomfort, and time required to complete ET. RESULT(S) Use of the Tomcat catheter resulted in significantly higher implantation (25.2% vs. 8.4%) and clinical pregnancy rates (47% vs. 14.7%) compared with the TDT catheter. All secondary outcome measures were similar for both catheters. CONCLUSION(S) The choice of ET catheter may affect the success of IVF-ET cycles. Use of the Tomcat catheter compared with the TDT catheter seems to result in significantly better efficiency of the ET procedure and is more cost effective.

Intracytoplasmic Sperm Injection After Follicle Stimulation with Highly Purified Human Follicle-Stimulating Hormone Compared with Human Menopausal Gonadotropin

Purpose:Our purpose was to compare oocyte nuclear maturation and embryo quality after pituitary down-regulation and ovarian stimulation with highly purified follicle-stimulating hormone (FSH) or human menopausal gonadotropin (HMG).Methods:Fifty-five patients 37 years of age or younger who were undergoing in vitro fertilization (IVF)–intracytoplasmic sperm injection (ICSI) were evaluated retrospectively. In all cases, male factor was the only indication for treatment, with no female-related factors identified. Following pituitary down-regulation, patients were stimulated with hMG (n = 20) or highly purified FSH (n = 35). Main outcome measures included ovarian response to stimulation, oocyte maturity, and ICSI fertilization results. Secondary outcome measures included pregnancy rates and outcome.Results:The ovarian response to stimulation was similar for the two groups, as were the percentage of metaphase II oocytes, fertilization and cleavage rates, and number and quality of transferred and cryopreserved embryos. Cycle outcome was comparable.Conclusions:In normogonadotropic subjects, monocomponent therapy with highly purified FSH is as effective as hMG in stimulating ovarian follicular development, synchronization of oocyte maturation, and IVF-ICSI outcome. Our findings support the conclusion that the luteinizing hormone component in the stimulation protocol is unnecessary.

Intracytoplasmic sperm injection for treatment of infertility due to acrosomal enzyme deficiency

OBJECTIVE To determine whether absence of fertilization in IVF associated with an acrosomal enzyme defect (hyaluronidase deficiency) results from a simple mechanical block to sperm penetration or from a more serious sperm abnormality. DESIGN Nonrandomized, prospective study. SETTING Toronto Center for Advanced Reproductive Technology, a tertiary referral center for infertility associated with The University of Toronto. PATIENTS One hundred twenty-two couples about to undergo intracytoplasmic sperm injection (ICSI) were selected. Thirty-six of the studied couples had failed to fertilize in prior IVF cycles. INTERVENTIONS Hyaluronidase activity was measured in the semen samples provided for ICSI using a zymogenic assay. Intracytoplasmic sperm injection was performed in all couples using standard techniques. RESULTS Forty-eight of 122 semen samples had poor of absent semen hyaluronidase activity. All 48 samples resulted in successful fertilization with ICSI in the present study. The average fertilization rate per oocyte was 59.43% in couples in whom the partner had low semen hyaluronidase activity and 55.85% in whom the male had normal hyaluronidase activity. The ET rate per cycle was 100% and 95% and pregnancy rates per cycles were 26% and 25% in cycles with poor and normal semen hyaluronidase activity, respectively. Unlike routine IVF, no statistical correlation was found between semen hyaluronidase activity and the fertilization rate in ICSI. CONCLUSION Our results indicates that semen hyaluronidase deficiency is associated with a simple mechanical block to fertilization. In addition, the measurement of semen hyaluronidase activity can provide a reliable means for selecting couples who would benefit from ICSI.

The hypo-osmotic swelling test for selection of viable sperm for intracytoplasmic sperm injection in men with complete asthenozoospermia**Supported by the Medical Research Council of Canada, Ottawa, Ontario, Canada.

OBJECTIVE To determine the ability of the hypo-osmotic swelling test to select viable sperm from nonmotile sperm samples for intracytoplasmic sperm injection (ICSI). DESIGN Nonrandomized, sequential comparative study. PATIENTS Thirteen couples enrolled in our ICSI program had 16 cycles in which sperm preparations with 0% motility were obtained. Five cycles used cryopreserved epididymal sperm with complete asthenozoospermia. INTERVENTIONS In eight cycles, the semen samples were washed through a Percoll gradient and sperm were selected randomly for ICSI. In another eight cycles, the washed sperm were placed in a hypo-osmotic solution (75 mM fructose; 25 mM sodium citrate dihydrate) and the sperm with curled tails taken up with the microinjection needle, rinsed, and used ICSI. MAIN OUTCOME MEASURES Fertilization rate per oocyte injected as determined by the presence of two pronuclei at 18 hours after retrieval and embryo cleavage rate per oocyte injected at 48 hours after retrieval. RESULTS With random sperm injection, the fertilization and cleavage rates were 26% and 23%, respectively. In contrast, after injection of sperm selected using the hypo-osmotic swelling test, fertilization and cleavage rates were significantly greater (43% and 39%, respectively). There were three pregnancies in the eight cycles with the hypo-osmotic swelling test-selected sperm, including two from frozen epididymal sperm. CONCLUSION Based on these preliminary observations, we believe that the hypo-osmotic swelling test will prove to be valuable for increasing fertilization and cleavage rates and pregnancy rates in ICSI cycles where no motile sperm are recovered.

Type of stimulation protocol affects oocyte maturity, fertilization rate, and cleavage rate after intracytoplasmic sperm injection**Presented at the 40th Annual Meeting of the Canadian Fertility and Andrology Society, St. Andrew’s-by-the-Sea, New Brunswick, Canada, September 7 to 10, 1994.

OBJECTIVE To compare oocyte maturity, fertilization rate and cleavage rate after a short and long GnRH agonist (GnRH-a) stimulation protocol and intracytoplasmic sperm injection (ICSI). DESIGN Retrospective study of 34 sequential ICSI cycles stimulated with a short or long GnRH-a protocol. SETTING A university-based tertiary care center for assisted reproductive treatment. RESULTS Significantly more oocytes were mature (metaphase II) after a long GnRH-a protocol then after a short GnRH-a protocol (25.6% and 80.8%, respectively). The long protocol resulted in more cleaving embryos (36/152 versus 9/132) and more cycles of ET (12/17 versus 5/17) than the short group. CONCLUSION A greater percentage of mature oocytes results from ovarian stimulation with a long GnRH-a protocol than a short GnRH-a protocol. Maturity could be assessed accurately after cumulus stripping that is required before ICSI. Fertilization rate and cleavage rate with ICSI was superior after a long GnRH-a stimulation protocol for superovulation.