L. Siano

GnRH agonist to induce oocyte maturation during IVF in patients at high risk of OHSS

The aim of this retrospective study was to evaluate the effectiveness of gonadotrophin-releasing hormone agonist (GnRHa) to trigger oocyte maturation in patients with polycystic ovarian syndrome (PCOS) or previous high response. The outcome of ovarian stimulation and IVF in patients using GnRHa to trigger oocyte maturation after co-treatment with GnRH antagonist (study group) was compared with patients using human chorionic gonadotrophin (HCG) to trigger oocyte maturation after a dual pituitary suppression protocol with oral contraceptive pill (OCP) and GnRHa overlap (control group). All patients received intramuscular progesterone for luteal support but patients in the study group received additional supplementation with oestradiol patches. The mean number of oocytes, proportion of mature oocytes and fertilization rate were similar between the study and control groups. Implantation rate (38.6% versus 45.1%), clinical pregnancy rate (69.6% versus 60.9%) and delivery rate (62.5% versus 56.5%) were similar in the study and control groups respectively. There was one case of moderate ovarian hyperstimulation syndrome (OHSS) in the control group and none in the study group. GnRHa is effective in triggering oocyte maturation in patients with PCOS or previous high response. Further randomized studies are required to evaluate its effectiveness in the prevention of OHSS in this group of patients.

Meiotic Arrest in Human Oocytes Is Maintained by a Gs Signaling Pathway

Abstract In mammalian oocytes, the maintenance of meiotic prophase I arrest prior to the surge of LH that stimulates meiotic maturation depends on a high level of cAMP within the oocyte. In mouse and rat, the cAMP is generated in the oocyte, and this requires the activity of a constitutively active, Gs–linked receptor, GPR3 or GPR12, respectively. To examine if human oocyte meiotic arrest depends on a similar pathway, we used RT-PCR and Western blotting to look at whether human oocytes express the same components for maintaining arrest as rodent oocytes. RNA encoding GPR3, but not GPR12, was expressed. RNA encoding adenylate cyclase type 3, which is the major adenylate cyclase required for maintaining meiotic arrest in the mouse oocyte, was also expressed, as was Gαs protein. To determine if this pathway is functional in the human oocyte, we examined the effect of injecting a function-blocking antibody against Gαs on meiotic resumption. This antibody stimulated meiotic resumption of human oocytes that were maintained at the prophase I stage using a phosphodiesterase inhibitor. These results demonstrate that human oocytes maintain meiotic arrest prior to the LH surge using a signaling pathway similar to that of rodent oocytes.

Predictive value of embryo grading for embryos with known outcomes

OBJECTIVE To compare pronuclear morphology (Z-score), day 3 embryo grade, and day 3 cell number in the prediction of successful implantation rates (IRs), including cycles in which all or none of the embryos implanted. DESIGN Retrospective analysis. SETTING University-based IVF center. PATIENT(S) Four hundred twenty-six fresh IVF day 3 transfers of 852 embryos in women <36 years of age from January 2000 to December 2003 in whom all or none of the embryos implanted. MAIN OUTCOME MEASURE(S) Evaluation of Z-scores, embryo morphology, cell number, and IR. RESULT(S) Day 3 parameters were more predictive than Z-scores. When early parameters were poor (Z-score) but late parameters were both good, the IR was 38%, compared with 4% when the Z-score was good but the late parameters were poor. CONCLUSION(S) Embryo grading systems are useful in the prediction of embryo implantation. In particular, cell number and embryo grade are more predictive than Z-scores. Therefore, late parameters have a better prognostic value than Z-scores when selecting embryos for transfer.

Intracytoplasmic sperm injection overcomes previous fertilization failure with conventional in vitro fertilization

OBJECTIVE To evaluate the outcome of intracytoplasmic sperm injection (ICSI) in patients with previous idiopathic fertilization failure (< or =20% fertilization rate) after conventional IVF. DESIGN Retrospective analysis. SETTING IVF program at a university medical center. PATIENT(S) Twenty-five patients who underwent 38 ICSI cycles after experiencing unexplained fertilization failure with conventional IVF (group A) and 87 patients who underwent 118 ICSI cycles for male factor indications during the same period (group B). INTERVENTION(S) Intracytoplasmic sperm injection was performed in a subsequent cycle after fertilization failure with conventional IVF. MAIN OUTCOME MEASURE(S) Outcomes of IVF were compared between groups A and B. RESULT(S) Fertilization was achieved with ICSI in all patients with previous fertilization failure. The mean (+/- SD) fertilization rate (68%+/-21% vs. 64%+/-22%), implantation rate per embryo (22.6% vs. 20%), and delivery rate per cycle (47.3% vs. 49.1%) did not differ significantly between groups A and B. Overall, 72% of patients with previous unexplained fertilization failure had a successful pregnancy after ICSI. CONCLUSION(S) Intracytoplasmic sperm injection can overcome unexplained fertilization failure caused by a potentially occult gamete abnormality, with the same fertilization, implantation, and pregnancy rates as are seen in patients with abnormal sperm parameters.

Reproductive efficiency of women over the age of 40 and the low risk of multiple pregnancies

Infertile patients over the age of 40 are generally considered to have a low chance of success with assisted cycles despite high numbers of embryos transferred. The risk of multiple pregnancy in this group of patients is not well established. The present study determined the rate of embryos that fail to produce a live birth and the rate of multiple pregnancies in a cohort of women over the age of 40 undergoing IVF/intracytoplasmic sperm injection cycles, utilizing Society for Assisted Reproductive Technology reported cycle outcomes from national summaries as well as from two university-based IVF centres. The rate of embryo wastage for women over the age of 40 is approximately 95% and these women have a correspondingly low rate of multiple pregnancy per cycle started (2.5% and 1.6% for women aged 41-42 years and 43-44 years, respectively). These data underscore the low reproductive efficiency of oocytes in women over the age of 40 and the very low probability of a multiple-gestation live birth despite the high number of embryos transferred. This information is an important additional counselling tool at the time of embryo transfer in this group of patients.