Limiting the number of injected oocytes to three impairs ICSI outcomes in patients with nonobstructive azoospermia

Use of testicular versus ejaculated sperm for intracytoplasmic sperm injection among men with cryptozoospermia: a meta-analysis

OBJECTIVE

To examine outcomes of intracytoplasmic sperm injection (ICSI) using testicular versus ejaculated sperm among men with cryptozoospermia.

DESIGN

Meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Men with cryptozoospermia undergoing consecutive ICSI cycles using ejaculated or testicular sperm.

INTERVENTION(S)

A systematic search was performed using PubMed (inception to August 2015). Inclusion criteria were studies comparing ICSI outcomes among men with cryptozoospermia using ejaculated and testicular sperm.

MAIN OUTCOME MEASURE(S)

Primary outcomes included ICSI fertilization or pregnancy rates (PRs). Secondary analysis included number of retrieved oocytes, maternal and paternal ages. Meta-analysis of weighted data using a random effects model was performed. Results are reported as relative risk or weighted mean differences (WMD) with 95% confidence intervals (CI).

RESULT(S)

Five cohort studies were included, encompassing 272 ICSI cycles and 4,596 injected oocytes. There were no differences in ICSI PRs (relative risk [RR] 0.53, 95% CI 0.19-1.42, I(2) = 67%) or fertilization rates (RR 0.91, 95% CI 0.78-1.06, I(2) = 73%) between testicular and ejaculated sperm groups. There was a significant trend toward increasing maternal age (WMD 1.69 years, 95% CI -2.71 to -0.66) and paternal age (WMD 2.61 years, 95% CI -4.73 to -0.48) with testicular sperm. There was no difference between numbers of oocytes retrieved (WMD 0.95, 95% CI -0.15 to 2.05). Post-hoc power analysis revealed pβ <20% for PR analysis and pβ <10% for fertilization rate analysis.

CONCLUSION(S)

The existing literature does not support a recommendation for men with cryptozoospermia to use testicular sperm in preference over ejaculated sperm for ICSI.

Paternal influence of sperm DNA integrity on early embryonic development

STUDY QUESTION

Does sperm DNA damage affect early embryonic development?

SUMMARY ANSWER

Increased sperm DNA damage adversely affects embryo quality starting at Day 2 of early embryonic development and continuing after embryo transfer, resulting in reduced implantation rates and pregnancy outcomes.

WHAT IS KNOWN ALREADY

Abnormalities in the sperm DNA in the form of single and double strand breaks can be assessed by an alkaline Comet assay. Some prior studies have shown a strong paternal effect of sperm DNA damage on IVF outcome, including reduced fertilization, reduced embryo quality and cleavage rates, reduced numbers of embryos developing into blastocysts, increased percentage of embryos undergoing developmental arrest, and reduced implantation and pregnancy rates.

STUDY DESIGN, SIZE, DURATION

A cross-sectional study of 215 men from infertile couples undergoing assisted reproduction techniques at the University of Utah Center for Reproductive Medicine.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Sperm from men undergoing ART were analyzed for DNA damage using an alkaline Comet assay and classified into three groups: 'low damage' (0-30%), 'intermediate damage' (31-70%) and 'high damage' (71-100%). The cause of couples' infertility was categorized into one of the three types (male, female or unexplained). Each embryo was categorized as 'good', 'fair' or 'poor' quality, based on the number and grade of blastomeres. The influence of sperm DNA damage on early embryonic development was observed and classified into four stages: peri-fertilization effect (fertilization rate), early paternal effect (embryonic days 1-2), late paternal effect (embryonic days 3-5) and implantation stage effect.

MAIN RESULTS AND THE ROLE OF CHANCE

The paternal effect of sperm DNA damage was observed at each stage of early embryonic development. The peri-fertilization effect was higher in oocytes from patients with female infertility (20.85%) compared with male (8.22%; P < 0.001) and unexplained (7.30%; P < 0.001) infertility factors. In both the early and late paternal effect stages, the low DNA damage group had a higher percentage of good quality embryos (P < 0.05) and lower percentage of poor quality embryos (P < 0.05) compared with the high DNA damage group. Implantation was lower in the high DNA damage (33.33%) compared with intermediate DNA damage (55.26%; P < 0.001) and low DNA damage (65.00%; P < 0.001) groups. The implantation rate was higher following blastocyst transfer (58.33%), when compared with early stage blastocyst (53.85%; P = 0.554) and cavitating morula transfers (34.40%; P < 0.001). Implantation was higher when the female partner age was ≤35 years when compared with >35 year age group (52.75 versus 35.44%; P = 0.008).

LIMITATIONS, REASONS FOR CAUTION

A potential limitation of this study is that it is cross-sectional. Generally in such studies more than one variable could affect the outcome. Analyzing sperm is one part of the equation but a number of environmental and female factors also have the potential to influence embryo development and implantation. Furthermore, the selection of morphologically normal and physiologically motile sperm may result in isolation of sperm with reduced DNA damage. Therefore, selecting the best available sperm for ICSI may lead to experimental bias, as the selected sperm do not represent the overall sperm population in which the DNA damage is measured. Similar studies on selected sperm and with a larger sample size are now required.

WIDER IMPLICATIONS OF THE FINDINGS

The paternal influence of damaged chromatin is more prominent after zygotic transcriptional activation. A prolonged paternal effect on the developing embryo may be due to the active repair mechanism present in oocytes that tends to overcome the damaged paternal chromatin. The probability of eliminating an embryo fertilized by a sperm with damaged DNA is higher at the blastocyst stage than the cleavage stage; therefore blastocyst transfer could be recommended for better implantation success. Finally, we recommend ICSI treatment for patients with a higher percentage of sperm with DNA damage as well as additional studies with a larger sample size aimed at assessing DNA damage analysis as a diagnostic tool for IVF.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the University of Utah internal funds. The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Five years (2004-2009) of a restrictive law-regulating ART in Italy significantly reduced delivery rate: analysis of 10,706 cycles

STUDY QUESTION

Was the delivery rate of ART cycles negatively affected by the enactment of the Law 40/2004 by the Italian Parliament which imposed a long list of restrictions for ART procedures?

SUMMARY ANSWER

This large and extensive comparative analysis of ART outcomes prior to and after the introduction of the Law 40 revealed a significant reduction in pregnancy and delivery rates per cycle, independent of age or other clinical variables, once the law went into effect.

WHAT IS KNOWN ALREADY

Several studies have been published on the effect of Law 40/2004 on ART outcomes, some authors demonstrating a negative impact of the Law in relation to specific etiologies of infertility, other authors showing opposite conclusions.

STUDY DESIGN, SIZE, DURATION

Retrospective clinical study of 3808 patients treated prior to the enactment of the Law, September 1996-March 2004 (Group I) and 6898 treated during the Law, March 2004-May 2009 (Group II).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 10 706 ART cycles were analysed, 3808 performed before and 6898 after the application of the Law. An intention-to-treat statistical analysis was performed to detect pregnancy and delivery rates (pregnancies ≥ 24 weeks) per started cycle. A P value of <0.05 was considered statistically significant. We analysed different outcomes: differences in fertilization, pregnancy and delivery rate, multiple pregnancies and miscarriage rates between the two time periods.

MAIN RESULTS AND THE ROLE OF CHANCE

The delivery rate for started cycle was 20% before and 16.0% after the introduction of the Law representing a 25% reduction (P < 0.001). The multivariate analysis, corrected by female age of >38 years, duration of infertility, basal FSH level and number of retrieved oocytes, showed a 16% lower delivery rate (odds ratio: 0.84; confidence interval: 0.75-0.94). This statistical approach removed the risk that the observed effects were due to chance and confirmed unequivocally that the Law was an independent factor responsible for the reduced likelihood of a successful outcome.

LIMITATIONS, REASONS FOR CAUTION

This is a retrospective study. A prospective randomized study, with patients treated in the same time period and randomized to restrictions or not, would have minimized potential limitations due to differences in years of treatments.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings based on the analysis of such a large number of cycles proved clearly and unequivocally that imposing restrictions on the practice of ART penalized patients. These data represent a relevant clinical contribution for countries still debating the enactment of restrictive limitations of ART.

Results and unsolved problems following the amendment to the Italian Law on assisted reproduction brought about by the Constitutional Court

Since the approval of Law N° 40/2004, Italian specialists have been applying assisted reproductive techniques in compliance with a number of restrictions. Several attempts were made to find a solution to the practical and ethical issues brought about by this restrictive legislation. Finally, in May 2009, the Italian Constitutional Court banned most of the limitations. In the last year the authors worked together to study the impact of the Italian Constitutional Court modifications on assisted reproduction from both a gynecological and medico-legal point of view. Despite the clinically positive impact of the ruling, a lot of technical and legal unsolved issues still exist. Analyzing these problems, the authors stress the importance of a multidisciplinary approach to achieve adequate legislation in order to improve patients' outcome and avoid "reproductive migration" from Italy to other European Countries. New regulation could also be important for practitioners by keeping the risk of legal troubles to the minimum.

The effect of the 2004 Italian law on outcomes of assisted reproduction technology in severe male factor infertility

The Italian law regulating assisted reproductive technologies that came into force in 2004 restricts the number of fertilized oocytes per cycle to three, obliges the subsequent transfer of all resulting embryos and prohibits the freezing of surplus embryos. This study evaluates the impact of the law on severe oligozoospermic, cryptozoospermic, obstructive azoospermic and non-obstructive azoospermic patients. Intracytoplasmic sperm injection outcomes of 1066 cycles performed in the 4years before the passing of the law were compared with 804 cycles performed in the 4years after the law came to pass. Globally, analysis of clinical and obstetric outcomes showed a significant decrease in terms of pregnancy and delivery rates per cycle (17.8% versus 10.9% and 14.2% versus 8.5%, respectively) and per embryo transfer (18.8% versus 13.8% and 15.0% versus 10.7%, respectively), and a significant drop in multiple deliveries (35.1% versus 17.6%) in the post-law period. Cryptozoospermic and azoospermic couples were affected by the Italian law more than severe oligozoospermic couples. The results showed that the Italian law limits the efficiency of assisted reproduction treatment in couples with severe male factor. It is hoped that the Italian assisted reproductive technologies law is altered as soon as possible, allowing the insemination of more than three oocytes.

Failed fertilization after ICSI and spermiogenic defects

OBJECTIVE

To evaluate the relationship between late spermiogenic events, including histone-protamine replacement, acrosome integrity, and sperm morphology, with fertilization rate after intracytoplasmic sperm injection (ICSI).

DESIGN

Prospective study.

SETTING

Isfahan Fertility and Infertility Center, Royan Institute, Tehran, Iran.

PATIENT(S)

Semen samples from 68 infertile couples undergoing ICSI at Isfahan Fertility and Infertility center were assessed during this study.

INTERVENTION(S)

Semen analysis was carried out according to World Health Organization criteria. Protamine deficiency, acrosin activity, sperm morphology, and acrosome size were assessed by chromomycin A3 (CMA3) staining, gelatinolysis test, and Papanicolaou staining (strict criteria), respectively.

MAIN OUTCOME MEASURE(S)

The correlation between protamine deficiency, sperm morphology, acrosin activity, and acrosome size with each other and fertilization rate were assessed.

RESULT(S)

Percentage CMA3 positivity and mean halo diameter show a significant correlation with fertilization rate. However, no correlation was found between sperm normal morphology and fertilization rate. The mean values of acrosome size and fertilization rate were significantly different when patients were grouped for CMA3 positivity of 40%. Multiple linear regression analysis revealed that only protamine deficiency has direct effect on fertilization rate.

CONCLUSION(S)

Protamine deficiency appears to have a more significant effect on fertilization after ICSI than acrosin activity and semen parameters.

Results of in vitro fertilization in Italy after the introduction of a new law

OBJECTIVE

To investigate the consequences of a law introduced in Italy in 2004 that forbids the fertilization or injection of more than three oocytes for assisted reproduction and does not allow any embryo selection or cryopreservation.

DESIGN

Retrospective observational analysis.

SETTING

Subfertile patients enrolled in an assisted reproduction program.

PATIENT(S)

Before the introduction of the law there were 1,179 cycles and after its enactment there were 1,860 cycles in 1,619 subfertile couples.

INTERVENTION(S)

Ovarian stimulation for IVF/intracytoplasmic sperm injection (ICSI) attempts.

MAIN OUTCOME MEASURE(S)

Pregnancy and implantation rate.

RESULT(S)

Pregnancy rates (PR) per cycle (24.34% vs. 23.11%), per retrieval (28.64% vs. 25.65%), per transfer (31.37% vs. 27.74%), and the take-home babies per started cycle (19.1% vs. 18%) was not significantly different between the two periods. After introduction of the law, the PR significantly decreased in patients whose total motile sperm count was <1 x 10(6) (40.85% vs. 23.62%) and in patients receiving two embryos (35.71% vs. 23.53%). This difference was mostly the result of a reduced PR in patients <36 years old receiving two unselected embryos (41.16% vs. 30.90%). This result was, however, obscured by the higher proportion of patients <36 years (3.9% vs. 45.12%) receiving three embryos after the enactment of the law, which lead to a significantly higher PR (28.73% vs. 37.56%) and a consequent significantly higher triplet rate (0.58% vs. 4.71%).

CONCLUSION(S)

Women in whom elective transfer of two embryos was allowed before passing the law and couples with a severe male infertility factor had significantly reduced success rates. Although the overall PR did not change after the new law, if the transfer of frozen embryos is not considered, this was mainly the result of a higher number of embryos transferred into women <36 years old. This study shows how the negative effects of the new law are obscured by the transfer of a higher number of embryos in younger patients, resulting in a higher PR at the cost of a significantly higher triplet rate.