A Danish national cohort of 730 infants born after intracytoplasmic sperm injection (ICSI) 1994-1997

Evolution of intracytoplasmic sperm injection: From initial challenges to wider applications

Background

In vitro fertilization (IVF) has revolutionized infertility treatment. Nevertheless, male infertility requires more effective solutions. In 1992, the first-ever case of human birth via intracytoplasmic sperm injection (ICSI) was reported. ICSI involves microscopically injecting a sperm into an ovum. Successful ICSI has become a reliable therapy for couples facing infertility, a significant milestone. However, it has also introduced various challenges. This study also delves into ethical dilemmas arising from widespread ICSI use.

Methods

This review traces the history of ICSI, presenting pioneering attempts, first successful attempts, and critical reports on account of the initial skepticism toward the technology. The review also focuses on chronological progress until ICSI was recognized as effective and became widely applied.

Main findings

The review reveals that ICSI, although transformative, presents challenges. Successes include addressing male infertility and aiding fertilization. However, concerns arise regarding optimal sperm and embryo selection, genetic mutations, and long-term health implications. Ethical considerations surrounding ICSI's broad applications also surface.

Conclusions

Despite its success and effectiveness, ICSI is still evolving as a therapeutic method. By comprehensively evaluating the historical progress and the current status of ICSI and exploring its future prospects, this study highlights the importance of ICSI in infertility treatment.

A systematic review and meta-analysis on the association between ICSI and chromosome abnormalities

BACKGROUND

In the decade following the introduction of ICSI, a higher prevalence of de novo chromosome abnormalities, in particular sex chromosome and autosomal structural abnormalities, as well as inherited abnormalities was described in children conceived by ICSI compared to both naturally conceived (NC) children and children conceived by standard IVF. The explanation for the observed increase in prevalence is not clear and has been suggested to reflect parental factors (e.g. age or sperm quality) or to be a result of the ICSI procedure itself. Over the years, the procedure, as well as the patient group, and indications for ICSI treatment have changed.

OBJECTIVE AND RATIONALE

The objective of this systematic review and meta-analysis was to assess the prevalence of chromosome abnormalities in ICSI pregnancies and children and to examine any potentially increased risk compared to standard IVF and NC.

SEARCH METHODS

Pubmed, Embase, Cochrane Libraries and Web of Science up to October 2020 were searched. Primary outcome measures were overall chromosome abnormalities and de novo abnormalities (including sex chromosome abnormalities and autosomal abnormalities). The secondary outcome was inherited abnormalities. We followed the PRISMA guidelines and relevant meta-analyses were performed.

OUTCOMES

The search included 4648 articles, out of which 27 met the inclusion criteria, and 19 were included in quantitative synthesis (meta-analyses). The prevalence of chromosome abnormalities varied considerably between studies, possibly explained by large differences in sample size and patient demographics. Only five studies were eligible for pooled analyses on adjusted data. All studies had a critical risk of bias. Results from pooled adjusted data showed no evidence of an increased risk of overall chromosome abnormalities when comparing ICSI to either standard IVF (aOR 0.75 (95% CI 0.41-1.38)) or NC (aOR 1.29 (95% CI 0.69-2.43)). In contrast, meta-analyses on unadjusted data showed an increased risk of overall chromosome abnormalities in ICSI compared to both standard IVF (OR 1.42 (95% CI 1.09-1.85)) and NC (OR 2.46 (95% CI 1.52-3.99)) and an increased risk of de novo abnormalities in ICSI compared to NC (OR 2.62 (95% CI 2.07-3.31)). Yet, based on a very low certainty of evidence, the conclusion remains, that no indication of an increased risk of chromosome abnormalities in ICSI offspring could be found. If an increased risk of chromosome abnormalities in selected ICSI offspring should exist, the absolute risk continues to be small.

WIDER IMPLICATIONS

This review provides an extensive overview of the existing evidence on the relationship between ICSI and chromosome abnormalities in the offspring. We highlight the need for well-designed large, prospective, controlled studies with systematic cytogenetic testing. Existing data are limited and, in many cases, marred by critical levels of bias.

Chromosomal abnormalities after ICSI in relation to semen parameters: results in 1114 fetuses and 1391 neonates from a single center

STUDY QUESTION

Is there a relationship between karyotype abnormalities in fetuses and children conceived by ICSI and their father's semen parameters?

SUMMARY ANSWER

The de novo chromosomal abnormality rate in pre- and postnatal karyotypes of ICSI offspring was higher than in the general population and related to fathers' sperm parameters.

WHAT IS KNOWN ALREADY

Several studies have reported a higher rate of de novo chromosomal anomalies in ICSI fetuses but recent data from large cohorts are limited. Overall, reported prevalences of non-inherited karyotype aberrations are increased in fetuses conceived after ICSI and vary between 1.6% and 4.2%. Only a few studies focus on the relation between karyotype anomalies in ICSI offspring and semen parameters of their fathers. Furthermore, an increased incidence of abnormal karyotypes in ICSI neonates has been described, but the rates vary widely across studies.

STUDY DESIGN, SIZE, DURATION

We report on karyotype results from prenatal testing by means of chorionic villus sampling and amniocentesis and results from postnatal blood sampling in offspring conceived by ICSI in a single center. Ongoing pregnancies resulting from an oocyte retrieval between January 2004 and December 2012 and after transfer of fresh ICSI embryos obtained using ejaculated or non-ejaculated sperm (fresh or frozen-thawed) were considered. Pregnancies following frozen embryo transfer, oocyte or sperm donation, IVF, preimplantation genetic testing and IVM were excluded. All abnormal prenatal results after sampling are reported irrespective of the outcome of the pregnancy.

PARTICIPANTS/MATERIALS, SETTING, METHODS

From the 4816 ongoing ICSI pregnancies, information on pregnancy outcome was available for 4267 pregnancies. Prenatal testing was performed in 22.3% of the pregnancies, resulting in a diagnosis in 1114 fetuses. A postnatal karyotype was obtained in 29.4% of the pregnancies in which no invasive prenatal diagnosis was performed, resulting in a total of 1391 neonates sampled. The prevalence of chromosomal anomalies according to maternal age and semen quality was analyzed with logistic regression. For definitions of normal semen quality, the World Health Organization reference values for human semen characteristics were adopted.

MAIN RESULTS AND THE ROLE OF CHANCE

An abnormal fetal karyotype was found in 29 singletons and 12 multiples (41/1114; 3.7%; 95% CI 2.7-4.9%): 36 anomalies were de novo (3.2%; 95% CI 2.3-4.4), either numerical (n = 25), sex (n = 6) or structural (n = 5), and five were inherited. Logistic regression analysis did not show a significant association between maternal age and a de novo chromosomal fetal abnormality (odds ratio (OR) 1.05; 95% CI 0.96-1.15; P = 0.24). In all but one case, fetuses with an abnormal karyotype were conceived by ICSI using ejaculated sperm.Abnormal karyotypes were found in 14 (1.0%; 95% CI 0.6-1.7) out of 1391 postnatal samples of children born after ICSI who were not tested prenatally: 12 were de novo anomalies and two were inherited balanced karyotypes. The 14 abnormal karyotypes were all found in children born after ICSI using ejaculated sperm.The odds of a de novo karyotype aberration increased with maternal age when combining pre- and postnatal data (OR 1.11; 95% CI 1.04-1.19). A higher rate of de novo chromosomal abnormalities was found in fetuses and children of couples with men having a sperm concentration <15 million/ml (adjusted OR (AOR) 2.10; 95% CI 1.14-3.78), sperm concentration <5 million/ml (AOR 1.9; 95% CI 1.05-3.45) and total sperm count <10 million (AOR 1.97; 95% CI 1.04-3.74).

LIMITATIONS, REASONS FOR CAUTION

We cannot exclude that the observation of a higher prevalence of karyotype anomalies in ICSI offspring compared to literature data in the general population is due to enhanced surveillance after ART given the lack of a control group. Although we did not find more chromosomal anomalies after ICSI with non-ejaculated sperm, the small numbers do not allow firm conclusions.

WIDER IMPLICATIONS OF THE FINDINGS

The observed increased risk of a de novo karyotype anomaly after ICSI conception in couples with poor sperm warrants continued counseling toward prenatal testing.The current and widespread use of innovative non-invasive prenatal testing will result in larger datasets, adding to a balanced estimation of the prevalence of karyotype anomalies in ICSI offspring.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Methusalem grants issued by the Vrije Universiteit Brussel. All authors declared no conflict of interest related to this study.

TRIAL REGISTRATION NUMBER

N/A.

Mortality from infancy to adolescence in singleton children conceived from assisted reproductive techniques versus naturally conceived singletons in Sweden

OBJECTIVE

To assess infant (<1 year) and childhood (1-18 years) mortality in singletons conceived through assisted reproductive techniques (ART) versus naturally conceived singletons.

DESIGN

Nationwide prospective study.

SETTING

Sweden.

PATIENT(S)

All singleton liveborn infants born from 1983 to 2012 in Sweden identified using the Medical Birth Register (N = 2,847,108), of whom 43,506 were conceived through ART treatments including in vitro fertilization with and without intracytoplasmic sperm injection.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURES(S)

Infant (<1 year) and childhood (1-18 years) mortality.

RESULT(S)

Data on ART treatment and covariates were retrieved from population-based registers using the unique personal identity number assigned to all permanent residents in Sweden. Cox proportional hazards models estimated the hazard ratios (HRs) with 95% confidence intervals (CIs) as measures of association between ART treatments and death. The analyses were adjusted for maternal characteristics, infertility, child sex, and birth cohort and were restricted to individuals with complete information on covariates for fully adjusted analysis. Compared with naturally conceived singletons, higher infant mortality risks were seen in infants conceived through ART (adjusted HR 1.45; 95% CI, 1.19-1.77), especially after transfer of cryopreserved embryos (adjusted HR 2.30; 95% CI, 1.46-3.64). Early neonatal mortality risk (deaths during the first week) was increased in children born after transfer of blastocysts (HR 2.40; 95% CI, 1.05-5.48). No increased mortality risk was observed between the ages of 1 and 18 years.

CONCLUSION(S)

Singletons conceived through ART had an increased risk of infant mortality from birth up to 1 year of life, predominantly in the early neonatal period and in pregnancies after transfer of frozen and thawed embryos.

Pregnancy and birth outcomes in couples with infertility with and without assisted reproductive technology: with an emphasis on US population-based studies

Infertility, defined as the inability to conceive within 1 year of unprotected intercourse, affects an estimated 80 million individuals worldwide, or 10-15% of couples of reproductive age. Assisted reproductive technology includes all infertility treatments to achieve conception; in vitro fertilization is the process by which an oocyte is fertilized by semen outside the body; non-in vitro fertilization assisted reproductive technology treatments include ovulation induction, artificial insemination, and intrauterine insemination. Use of assisted reproductive technology has risen steadily in the United States during the past 2 decades due to several reasons, including childbearing at older maternal ages and increasing insurance coverage. The number of in vitro fertilization cycles in the United States has nearly doubled from 2000 through 2013 and currently 1.7% of all live births in the United States are the result of this technology. Since the birth of the first child from in vitro fertilization >35 years ago, >5 million babies have been born from in vitro fertilization, half within the past 6 years. It is estimated that 1% of singletons, 19% of twins, and 25% of triplet or higher multiples are due to in vitro fertilization, and 4%, 21%, and 52%, respectively, are due to non-in vitro fertilization assisted reproductive technology. Higher plurality at birth results in a >10-fold increase in the risks for prematurity and low birthweight in twins vs singletons (adjusted odds ratio, 11.84; 95% confidence interval, 10.56-13.27 and adjusted odds ratio, 10.68; 95% confidence interval, 9.45-12.08, respectively). The use of donor oocytes is associated with increased risks for pregnancy-induced hypertension (adjusted odds ratio, 1.43; 95% confidence interval, 1.14-1.78) and prematurity (adjusted odds ratio, 1.43; 95% confidence interval, 1.11-1.83). The use of thawed embryos is associated with higher risks for pregnancy-induced hypertension (adjusted odds ratio, 1.30; 95% confidence interval, 1.08-1.57) and large-for-gestation birthweight (adjusted odds ratio, 1.74; 95% confidence interval, 1.45-2.08). Among singletons, in vitro fertilization is associated with increased risk of severe maternal morbidity compared with fertile deliveries (vaginal: adjusted odds ratio, 2.27; 95% confidence interval, 1.78-2.88; cesarean: adjusted odds ratio, 1.67; 95% confidence interval, 1.40-1.98, respectively) and subfertile deliveries (vaginal: adjusted odds ratio, 1.97; 95% confidence interval, 1.30-3.00; cesarean: adjusted odds ratio, 1.75; 95% confidence interval, 1.30-2.35, respectively). Among twins, cesarean in vitro fertilization deliveries have significantly greater severe maternal morbidity compared to cesarean fertile deliveries (adjusted odds ratio, 1.48; 95% confidence interval, 1.14-1.93). Subfertility, with or without in vitro fertilization or non-in vitro fertilization infertility treatments to achieve a pregnancy, is associated with increased risks of adverse maternal and perinatal outcomes. The major risk from in vitro fertilization treatments of multiple births (and the associated excess of perinatal morbidity) has been reduced over time, with fewer and better-quality embryos being transferred.

Use of ICSI in IVF cycles in women with tubal ligation does not improve pregnancy or live birth rates

STUDY QUESTION

Does ICSI improve outcomes in ART cycles without male factor, specifically in couples with a history of tubal ligation as their infertility diagnosis?

SUMMARY ANSWER

The use of ICSI showed no significant improvement in fertilization rate and resulted in lower pregnancy and live birth (LB) rates for women with the diagnosis of tubal ligation and no male factor.

WHAT IS KNOWN ALREADY

Prior studies have suggested that ICSI use does not improve fertilization, pregnancy or LB rates in couples with non-male factor infertility. However, it is unknown whether couples with tubal ligation only diagnosis and therefore iatrogenic infertility could benefit from the use of ICSI during their ART cycles.

STUDY DESIGN, SIZE, DURATION

Longitudinal cohort of nationally reported cycles in the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System (SART CORS) of ART cycles performed in the USA between 2004 and 2012.

PARTICIPANTS/MATERIALS, SETTING, METHODS

There was a total of 8102 first autologous fresh ART cycles from women with the diagnosis of tubal ligation only and no reported male factor in the SART database. Of these, 957 were canceled cycles and were excluded from the final analysis. The remaining cycles were categorized by the use of conventional IVF (IVF, n = 3956 cycles) or ICSI (n = 3189 cycles). The odds of fertilization, clinical intrauterine gestation (CIG) and LB were calculated by logistic regression modeling, and the adjusted odds ratios (AORs) with 95% confidence intervals were calculated by adjusting for the confounders of year of treatment, maternal age, race and ethnicity, gravidity, number of oocytes retrieved, day of embryo transfer and number of embryos transferred.

MAIN RESULTS AND THE ROLE OF CHANCE

The main outcome measures of the study were odds of fertilization (2PN/total oocytes), clinical intrauterine gestation (CIG/cycle) and live birth (LB/cycle). The fertilization rate was higher in the ICSI versus IVF group (57.5% vs 49.1%); however, after adjustment this trend was no longer significant (AOR 1.14, 0.97-1.35). Interestingly, both odds of CIG (AOR 0.78, 0.70-0.86), and odds of LB were lower (AOR 0.77, 0.69-0.85) in the ICSI group. Plurality at birth, mean length of gestation and birth weight did not differ between the two groups.

LIMITATIONS, REASONS FOR CAUTION

This was a retrospective study, therefore only the available parameters could be included, with parameters of interest such as smoking status not available for inclusion. Smoking status may have led practitioners to use ICSI to improve pregnancy and LB outcomes.

WIDER IMPLICATIONS OF THE FINDINGS

Studies have shown that in the USA there is an increasing usage of ICSI for non-male factor infertility despite a lack of evidence-based benefit. Our study corroborates this increasing use over the last 8 years, specifically in the tubal ligation only patient population. Even after adjusting for multiple confounders, the patients who underwent ICSI had no statistically significant improvement in fertilization rate and actually had a lower likelihood of achieving a clinical pregnancy and LB. Therefore, our data suggest that the use of ICSI in tubal ligation patients has no overall benefit. This study contributes to the body of evidence that the use of ICSI for non-male factor diagnosis does not improve ART outcomes over conventional IVF.

STUDY FUNDING/COMPETING INTERESTS

None.

Does infertility treatment increase male reproductive tract disorder?

OBJECTIVE

To determine the association between assisted human reproduction and male reproductive disorders in infants conceived by this means.

MATERIALS AND METHODS

Between January 2008 and December 2011, 15,332 neonates were born in our hospital. We assessed the birth weight, gestational age, and other characteristics of the 7752 male infants and determined the association between methods of conception and male reproductive disorders in the infants. We also analyzed the influence of male factor on the occurrence of these disorders.

RESULTS

Ninety-nine newborns (1.3%) were diagnosed with cryptorchidism, 8 (0.1%) were diagnosed with hypospadias, and 4 (0.05%) were diagnosed with both. Cryptorchidism was more common in children conceived through in vitro fertilization (IVF) and IVF/intracytoplasmic sperm injection (IVF/ICSI; P <.05), and hypospadias was more common in children conceived through IVF/ICSI (P <.05). Children conceived through intrauterine insemination (IUI), IVF, and IVF/ICSI had higher rates of low birth weight and preterm birth. Logistic regression analysis showed that low birth weight and preterm birth were significantly associated with male reproductive disorders, whereas the method of conception was not. Male factor was not significantly associated with these disorders.

CONCLUSION

IVF and IVF/ICSI increase the risks of low birth weight and preterm birth, resulting in increased rates of hypospadias and cryptorchidism. Male factor was not associated with reproductive disorders in male infants.

Cytogenetic findings and reproductive outcome of infertile couples referred to an assisted reproduction program

It is still undefined whether all the couples entering an assisted reproduction program should undergo to karyotype analysis. The present study was conducted to determine the prevalence of chromosomal abnormalities in a non-selected sample of 1,146 couples referred to assisted reproduction technologies (ART), and to analyze the outcome of pregnancies from couples in whom cytogenetic anomalies were detected. Irrespective of the infertility factor, fertilization was achieved by intracytoplasmic sperm injection (ICSI). A total number of 35 karyotype anomalies were diagnosed, corresponding to an abnormality frequency of 1.52% (1.83% for men and 1.22% for women). As could be expected, the majority of men presenting karyotype anomalies had a low sperm count. Among women, the majority of cytogenetic anomalies were detected in individual not presenting risk factors for aberrant karyotype. Around 41% of pregnancies achieved in couples presenting chromosomal anomalies ended in spontaneous abortion. Information on fetal karyotype was limited. No major malformations were observed among newborns from parents with abnormal karyotype. In consideration of the elevated frequency of pregnancy loss, it seems advisable to recommend that chromosomal analysis be performed in all couples undergoing ART. This with the aim of identifying patients that would possibly benefit from pre-implantation genetic diagnosis.

[Is there more complications with pregnancies from the assisted reproductive technology than spontaneous pregnancies? A retrospective study over 6 years]

OBJECTIVES

Comparison of pregnancy pathologies (diabetes, high blood pressure, preeclampsia), the stages of delivery, the weight at birth, the method of delivery, and the neonatal outcome for spontaneous pregnancies, and pregnancies from assisted reproductive technology (ART) obtained by in vitro fertilization (IVF), by intra cytoplasmic sperm injection (ICSI) or intrauterine insemination (IUI) or ovulation induction.

PATIENTS AND METHODS

A retrospective study over 6 years from January 1st, 2003 and December 31st, 2008 including all births at Jean-Verdier hospital in Bondy, France (n=14,049) taking into account therapeutic abortions, late miscarriages and intrauterine fetal deaths. The population was divided into four groups: spontaneous pregnancies (SP), pregnancies resulting from IVF, those obtained by ICSI and those obtained by other modes of "simple" ART.

RESULTS

The distribution of the four populations is: SP: 96.5%, IVF: 1.20%, ICSI: 0.95% and other modes of "simple" ART: 1.35%. There is no significant difference in rates of high blood pressure, preeclampsia, HELLP syndrome, therapeutic abortions and intrauterine fetal deaths between the four populations studied. In contrast, ICSI has a rate of gestational diabetes significantly lower compared to the other three groups (6.7%). The terms of delivery are later and birth weight heavier for spontaneous pregnancies (P<0.05). For the singletons, the terms of delivery are later for "heavy" ART (IVF/ICSI) than for SP (P<0.05). For twins' birth weights, we notice that they are heavier for ICSI (P<0.05) and the terms of delivery are identical between the SP and heavy ART.

CONCLUSION

Our study showed no obstetrical complications for the heavy ART (IVF/ICSI). Pregnancies resulting from ICSI are more favourable than those from IVF and the most unfavourable are the one obtained by simple ART.

ICSI: Hype or hazard?

Ever since its introduction in clinical practice more than 10 years ago, intracytoplasmic sperm injection (ICSI) has been the subject of ongoing debate regarding its indications and safety. ICSI is hyped because of its potential to give couples with severe male factor infertility a chance to conceive, and because of its apparently low fertilization failure rate compared with 'classic' in vitro fertilization (IVF). Concerns about ICSI are related to technical, biological and genetic hazards. ICSI has been branded 'the ultimate rape of the oocyte', as the oocyte membrane is mechanically pierced, appearing to bypass all biological and genetic selection. ICSI has been linked in a number of reports to an increased incidence of chromosomal anomalies, congenital abnormalities and perinatal hazards in offspring conceived with this technique. The etiology of the increased risk of chromosomal anomalies in ICSI offspring, especially sex-chromosome anomalies, is thought to be partly multifactorial, partly andrological, related to paternal karyotypic abnormalities and/or abnormal sperm. The majority of studies on ICSI and IVF offspring have, setting aside inconsistencies in methodology and classification, not shown significant differences between the two techniques in terms of congenital abnormalities, however, compared to naturally conceived offspring there does show an increased risk. This risk is attributed mainly to parental factors such as maternal age, poor sperm quality and infertility as an independent risk factor. Perinatal hazards may include low birth weight and perinatal mortality. Behavioural and psychological development is carefully monitored in ICSI and IVF children with no significant differences to the development of naturally conceived children, but many factors are involved including demographics. Follow-up studies are essential to the technique of ICSI. It is our duty to inform patients of the concerns and benefits to this treatment, based on the latest data available.

Intracytoplasmic sperm injection (ICSI)--what are the risks?

In vitro fertilization used in combination with intracytoplasmic sperm injection allows otherwise sterile couples to become parents. Despite recent studies on the safety of these technologies, there is still only an incomplete picture of the risks associated with the usage of these assisted reproductive techniques to offspring. The risk of multiple gestations continues to be of major concern because of its association with low birth weight, preterm delivery, and increased perinatal mortality. This article outlines the risks associated with in vitro fertilization/intracytoplasmic sperm injection as a well-defined treatment for couples with severe male factor infertility.

Does confined placental mosaicism account for adverse perinatal outcomes in IVF pregnancies?

BACKGROUND

IVF singletons have poorer perinatal outcomes than singletons from spontaneous conceptions. This may be due to the influence of ovarian stimulation on the chromosomal constitution of the embryos which could be translated into localized chromosomal anomalies in the placenta. The aim of this study was to compare the incidence of confined placental mosaicism (CPM) in IVF/ICSI pregnancies and spontaneous conceptions.

METHODS

We conducted a multi-centre retrospective analysis of karyotype results obtained by chorionic villus sampling (CVS), performed due to advanced maternal age (>or=36 years at 18 weeks of gestation), in the Netherlands between 1995 and 2005.

RESULTS

From a total of 322 246 pregnancies, 20 885 CVS results were analysed: 235 in the IVF/ICSI group and 20 650 in the control group. The mean age of women in both groups was 38.4 years (mean difference -0.08, 95% CI -0.35 to 0.18). Data relating to the fetal karyotype were missing in 143 cases in the control group. When taking into account missing data, the incidence of CPM was lower in the IVF-ICSI group than in the control group, 1.3% versus 2.2% (odds ratio 0.59, 95% CI 0.19-1.85), whereas the incidence of fetal chromosomal anomalies was increased 4.3% versus 2.4% (odds ratio 1.81, 95% CI 0.95-3.42). Neither differences were statistically significant.

CONCLUSIONS

The incidence of CPM is not increased in IVF/ICSI pregnancies compared with spontaneous conceptions. CPM probably does not account for the adverse perinatal outcomes following IVF/ICSI.

Safety of assisted reproduction, assessed by risk of abnormalities in children born after use of in vitro fertilization techniques

Assisted reproductive technologies are increasingly used in the treatment of both male and female infertility. The techniques, including in vitro fertilization, with or without intracytoplasmic sperm injection as an adjunctive treatment, represent a tremendous step forward for infertile couples who previously had no treatment options. As we move towards the 30(th) anniversary of the birth of the first baby conceived by in vitro fertilization, questions about the safety of these procedures linger. We review here the available literature regarding the safety of assisted reproductive technologies; these data are made far more robust by the inclusion of long-term follow-up data from the first generation of children arising after the introduction of these technologies.

Comparison of embryo quality between intracytoplasmic sperm injection and in vitro fertilization in sibling oocytes

BACKGROUND

The aim of the present study was to compare the quality of embryos derived from sibling oocytes by in vitro fertilization (IVF) or ICSI.

METHODS

Consecutive patients with a less than 40% fertilization rate in a previous standard IVF cycle or with relative male factor infertility were recruited for the study. The oocytes retrieved from each patient were divided into two groups for either conventional insemination (group A) or ICSI (group B). Power analysis showed that to detect a 25% difference in the rate of high-quality embryos between the groups with a power of 0.8, at least 1,200 oocytes were needed in each group.

RESULTS

One hundred seventy-seven patients were included in the study. Group A was comprised of 1,526 oocytes and group B of 1,480 sibling oocytes. As expected, the fertilization rate was significantly higher in group B than group A (67.1 vs. 43.6%, p < 0.001). No significant between-group differences were observed in cleavage rate (92.7 and 89.7%, respectively) and the rate of either grade A embryos (22.6 and 23.9%, respectively) or grade A(1) embryos (37.3 and 33.5%, respectively). However, in the subgroup of patients with relative male-factor infertility (n = 36), the rate of grade A(1) embryos was significantly higher in the IVF than the ICSI group (46.4 vs. 29.0%, respectively, p = 0.02).

CONCLUSIONS

Embryo quality does not seem to be influenced by the mode of fertilization (IVF or ICSI). We assume that embryo quality depends on intrinsic factors of the gametes involved rather than on the fertilization process per se.

Pregnancy outcomes after assisted reproductive technology

OBJECTIVE

To review the effect of assisted reproductive technology (ART) on perinatal outcomes, to provide guidelines to optimize obstetrical management and counselling of Canadian women using ART, and to identify areas specific to birth outcomes and ART requiring further research.

OPTIONS

Perinatal outcomes of ART pregnancies in subfertile women are compared with those of spontaneously conceived pregnancies. Perinatal outcomes are compared between different types of ART.

OUTCOMES

This guideline discusses the adverse outcomes that have been recorded in association with ART, including obstetrical complications, adverse perinatal outcomes, multiple gestations, structural congenital abnormalities, chromosomal abnormalities, imprinting disorders, and childhood cancer.

EVIDENCE

The Cochrane Library and MEDLINE were searched for English-language articles from 1990 to February 2005, relating to assisted reproduction and perinatal outcomes. Search terms included assisted reproduction, assisted reproductive technology, ovulation induction, intracytoplasmic sperm injection (ICSI), embryo transfer, and in vitro fertilization (IVF). Additional publications were identified from the bibliographies of these articles as well as the Science Citation Index. Studies assessing gamete intrafallopian transfer (GIFT) and zygote intrafallopian transfer (ZIFT) were excluded since they are rarely used in Canada. All study types were reviewed. Randomized controlled trials were considered evidence of the highest quality, followed by cohort studies. Key studies and supporting data for each recommendation are summarized with evaluative comments and referenced.

VALUES

The evidence collected was reviewed by the Genetics Committee and the Reproductive Endocrinology Infertility Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and quantified using the Evaluation of Evidence Guidelines developed by the Canadian Task Force on the Periodic Health Examination.

BENEFITS, HARMS, AND COSTS

The type and magnitude of benefits, harms, and costs expected for patients from guideline implementation. This guideline has been reviewed by the Genetics Committee and the Reproductive Endocrinology and Infertility Committee, and approved by the Executive and Council of the Society of Obstetricians and Gynaecologists of Canada and the Board of the Canadian Fertility and Andrology Society.

RECOMMENDATIONS

1. Spontaneous pregnancies in untreated infertile women may be at higher risk for obstetrical complications and perinatal mortality than spontaneous pregnancies in fertile women. Further research is required to clarify the contribution of infertility itself to adverse obstetrical and perinatal outcomes. (II-2A) 2. All men with severe oligozoospermia or azoospermia should be offered genetic/clinical counselling for informed consent and offered karyotyping for chromosomal abnormalities before attempting IVF-ICSI. They should be made aware of the availability of tests for Y chromosome microdeletion. Some patients may consider the option of donor insemination. (II-3B) 3. Couples exploring IVF-ICSI when the man has obstructive azoospermia should be offered genetic/clinical counselling for informed consent and offered genetic testing for alterations in genes associated with cystic fibrosis (CF) before attempting IVF-ICSI. (II-2A) 4. Pregnancies achieved by ovarian stimulation with gonadotropins and intrauterine insemination are at higher risk for perinatal complications, and close surveillance during pregnancy should be considered. It remains unclear if these increased risks are attributable to the underlying infertility, characteristics of the infertile couple, or use of assisted reproductive techniques. Multiple gestations remain a significant risk of gonadotropin treatment. (II-2A) 5. Pregnancies achieved by IVF with or without ICSI are at higher risk for obstetrical and perinatal complications than spontaneous pregnancies, and close surveillance during pregnancy should be considered. It remains unclear if these increased risks are attributable to the underlying infertility, characteristics of the infertile couple, or use of assisted reproductive techniques. (II-2A) 6. Women undergoing ART should be informed about the increased rate of obstetrical interventions such as induced labour and elective Caesarean delivery. (II-2A) 7. Couples suffering from infertility who are exploring treatment options should be made aware of the psychosocial implications of ART. Further research into the psychosocial impact of ART is needed. (II-2A) 8. Singleton pregnancies achieved by assisted reproduction are at higher risk than spontaneous pregnancies for adverse perinatal outcomes, including perinatal mortality, preterm delivery, and low birth weight, and close surveillance during pregnancy should be available as needed. (II-2A) 9. A significant risk of ART is multiple pregnancies. Infertile couples need to be informed of the increased risks of multifetal pregnancies. Although dichorionic twins are most common, the incidence of monochorionic twins is also increased. Risks of multiple pregnancies include higher rates of perinatal mortality, preterm birth, low birth weight, gestational hypertension, placental abruption, and placenta previa. Perinatal mortality in assisted conception twin pregnancies appears to be lower than in spontaneously conceived twin pregnancies. (II-2A) 10. When multifetal reduction is being considered for high-order multiple pregnancies, psychosocial counselling should be readily available. Careful surveillance for fetal growth problems should be undertaken after multifetal reduction. (II-2A) 11. To reduce the risks of multiple pregnancies associated with ART and to optimize pregnancy rates, national guidelines should be developed on the number of embryos replaced according to characteristics such as patient's age and grade of embryos. (II-2A) 12. Further epidemiologic and basic science research is needed to help determine the etiology and extent of the increased risks to childhood and long-term growth and development associated with ART. (II-2A) 13. Discussion of options for prenatal screening for congenital structural abnormalities in pregnancies achieved by ART is recommended, including appropriate use of biochemical and sonographic screening. (II-2A) 14. Further epidemiologic and basic science research is needed to help determine the etiology and extent of the increased risks of congenital abnormalities associated with ART. (II-2A) 15. Couples considering IVF-ICSI for male-factor infertility should receive information, and if necessary formal genetic counselling, about the increased risk of de novo chromosomal abnormalities (mainly sex chromosomal anomalies) associated with their condition. Prenatal diagnosis by chorionic villus sampling (CVS) or amniocentesis should be offered to these couples if they conceive. (II-2A) 16. Further epidemiologic and basic science research is needed to help determine the etiology and extent of the increased risks of chromosomal abnormalities associated with ART. (II-2A) 17. Discussion of options for prenatal screening and testing for aneuploidy in pregnancies achieved by ART, adapted for maternal age and number of fetuses, is recommended, including appropriate use of biochemical and sonographic screening. (II-2A) 18. The precise risks of imprinting and childhood cancer from ART remain unclear but cannot be ignored. Further clinical research, including long-term follow-up, is urgently required to evaluate the prevalence of imprinting disorders and cancers associated with ART. (II-2A) 19. The clinical application of preimplantation genetic diagnosis must balance the benefits of avoiding disease transmission with the medical risks and financial burden of in vitro fertilization. Further ethical discussion and clinical research is required to evaluate appropriate indications for preimplantation genetic diagnosis. (III-B).

A prospective randomized trial of conventional in vitro fertilization versus intracytoplasmic sperm injection in unexplained infertility

PURPOSE

To compare outcomes in patients with unexplained infertility undergoing conventional in vitro fertilization (IVF) versus intracytoplasmic sperm injection (ICSI).

METHODS

Sixty women with unexplained infertility in a Canadian tertiary-level clinic were randomized to IVF or ICSI. Subjects underwent downregulation with gonadotropin-releasing hormone agonist prior to initiation of recombinant human follicle-stimulating hormone. The primary outcome measure was fertilization rate. Secondary outcomes included implantation rate, embryo quality, clinical pregnancy rate, and live birth rate.

RESULTS

There was no statistically significant difference in fertilization rate (77.2% IVF vs. 82.4% ICSI), implantation rate (38.2% IVF vs. 44.4% ICSI), clinical pregnancy rate (50% in each group), or live birth rate (46.7% IVF vs. 50% ICSI). There were two cases of failed fertilization in the IVF group. There was no significant difference in embryo quality between groups.

CONCLUSIONS

There were no differences in clinical outcomes associated with IVF versus ICSI in the treatment of unexplained infertility.

Children born after assisted fertilization have an increased rate of major congenital anomalies

OBJECTIVE

To study the occurrence of major congenital anomalies (CAs) among children born after IVF (IVF, microinjections, and frozen embryo transfers) and after ovulation inductions with or without insemination (other assisted reproductive technologies [ART]).

DESIGN

Register-based study.

SETTING

Data regarding CAs were obtained from the Register of Congenital Malformations.

PATIENT(S)

Children from IVF (n = 4,559), children from other ART (n = 4,467), and controls (n = 27,078, a random sample of naturally conceived children) from the Medical Birth Register.

INTERVENTION(S)

In vitro fertilization and other ART treatment in ordinary practice.

MAIN OUTCOME MEASURE(S)

Rate of major CAs. Children from IVF and other ART were compared with control children, both overall and by plurality, controlling for confounding factors by logistic regression.

RESULT(S)

For IVF children, the adjusted odds ratio (OR) was 1.3 (95% confidence interval [CI], 1.1-1.6). Stratifying by gender and plurality showed that the risk was only increased for boys, and the risk was decreased for multiple IVF girls (OR = 0.5, 95% CI 0.2-0.9). The crude OR of major CA for other ART children was 1.3 (95% CI 1.1-1.5), but adjusted differences by gender and plurality were statistically insignificant.

CONCLUSION(S)

In vitro fertilization was associated with an increased risk for major CAs among singleton boys and a decreased risk among multiple girls. The risk after other ART was only slightly increased.

Antenatal care in singleton pregnancies after ICSI as compared to spontaneous conception: data from a prospective controlled cohort study in Germany

BACKGROUND

The aim was to compare the antenatal care and the intake of vitamins and medications of infertility patients with singleton pregnancies after ICSI to women with a spontaneously conceived singleton pregnancy.

METHODS

The data on the antenatal care of 2055 singleton pregnancies after ICSI from a prospective controlled multicentre study in Germany were analysed. The prospectively collected data of the control group of 7861 singletons were retrospectively assessed for the present analysis.

RESULTS

The ICSI patients were significantly older (32.9 versus 27.0 years, P<0.019) and more likely to be obese (body mass index>or=30 kg/m2: 13.9 versus 4.8%, P<0.001) than the controls. The control mothers were significantly more likely to smoke (19.2%) or to consume alcohol (23.5%) during pregnancy than the ICSI mothers (7.4 and 0.6% respectively). Only 38.1% of ICSI patients took folic acid before conception. Only 61.7% of ICSI patients received an iodine supplementation at some point during pregnancy. ICSI patients went more regularly to the routine antenatal care consultations at the gynaecologist and had ultrasound examinations performed more regularly than the controls. The absolute number of ultrasound examinations was significantly higher in the ICSI group (13.6+/-6.0 versus 4.1+/-2.4).

CONCLUSION

In spite of the intensive use of antenatal medical care by patients pregnant after ICSI, simple methods, such as the use of supplementary iodine and periconceptional folic acid, were used rarely. This indicates that counselling pregnant patients after ICSI about periconceptional and antenatal care seems to be insufficient in Germany and must be improved.

Two-year neurodevelopmental outcome in children conceived by intracytoplasmic sperm injection: prospective cohort study

OBJECTIVE

Primary outcome was to compare neurodevelopmental outcome at two years in intracytoplasmic sperm injection (ICSI) conceived children versus matched controls. Secondary outcome was to determine incidence of major congenital malformations and study perinatal outcome.

DESIGN

Prospective cohort study.

SETTING

Tertiary care perinatal centre over a period of 13 months.

POPULATION

Seventy-six ICSI conceived children and 261 matched controls selected by matching for maternal age, sex, date of delivery, race, plurality and parity.

METHODS

Mental Development Index (MDI) and Psychometric Development Index (PDI) of the Bayley's Scale of Development (BSID-II) and Vineland Adaptive Behaviour Scale (VABS) were used to assess the neurodevelopmental and functional outcome. The congenital malformations were classified according to ICD-9 code.

MAIN OUTCOME MEASURES

Primary outcome measure--neurodevelopmental and functional outcomes. Secondary outcome measure--congenital malformations and perinatal outcomes.

RESULTS

Neurodevelopmental and functional outcome were comparable in both groups. The mean MDI score was 92 [16] versus 90 [14] in the study and control groups respectively. Fourteen (18.4%) in the ICSI group had MDI <85 compared with 87 (33%) controls (P= 0.002). On linear regression the MDI was independently affected by plurality (P= 0.001), maternal education and socio-economic status (P= 0.01). The study group had a lower gestation (36 [3] vs 37.1 [2] weeks; P= 0.005) and a higher incidence of prematurity <34 weeks [19 (25%)] vs [31 (12%)] P= 0.012]. Six (7.9%) of the ICSI babies and seven (2.7%) of the controls had a major congenital malformation (P= 0.05).

CONCLUSIONS

Children born by ICSI pregnancies did not have an adverse neurodevelopmental outcome. The incidence of major congenital malformations in ICSI needs further evaluation.

IVF/ICSI twin pregnancies: risks and prevention

Since the 1970s, the national twin birth rates have been increasing worldwide. Apart from the increasing childbearing age, the main cause is the use of assisted reproductive technologies (ART). To explore the overall consequences of dual embryo transfer (DET), the literature has been reviewed systematically regarding short- and long-term outcomes of IVF/ICSI twin pregnancies i.e. pregnancy complications, maternal risks, obstetric outcome and long-term morbidity including neurological sequelae, cognitive development and family implications. Another consequence of DET is vanishing twins, which seems to be a possible cause of adverse outcome in IVF singletons. The sparse literature on vanishing twins in IVF pregnancies and the influence on the surviving co-twin were also addressed. Finally, to determine the effects of implementing elective single embryo transfer (eSET), trials concerning eSET versus DET were analysed. In the light of the steadily increasing twin birth rates and the findings in this overview, where IVF/ICSI twins carry adverse outcome, it should be emphasized that the major obstacle in IVF remains the high twin birth rate. Furthermore vanishing twins account for another hazard of DET. These problems can be resolved by implementing eSET, diminishing the twin birth rate without affecting the overall goal of achieving a healthy infant.

Birth defects in children conceived by ICSI compared with children conceived by other IVF-methods; a meta-analysis

BACKGROUND

Intracytoplasmic sperm injection (ICSI) is a method of assisted reproductive technology that involves the selection of a single sperm cell and the manual injection of this cell into the egg. The lack of relevant experimental studies, the nature of the technology involving non-natural selection of the fertilizing sperm, and possible damage to the egg have caused concern that ICSI could increase the risk of birth defects. Data from available cohort studies comparing ICSI with standard in vitro fertilization (IVF) should be combined to evaluate the risks involved with ICSI.

METHODS

We reviewed more than 2500 titles and abstracts containing keywords related to ICSI and identified 22 scientific articles with data on birth defects among ICSI-births. A total of four peer-reviewed, non-overlapping prospective cohort studies provided reliable and comparable data on birth defects both for children conceived by ICSI and children conceived by standard IVF. These studies included a total of 5395 children born after ICSI.

RESULTS

The pooled estimate of the risk of a major birth defect was a 1.12-fold increase after ICSI when compared with standard IVF (risk ratio = 1.12, 95% confidence interval (CI): 0.97-1.28, P = 0.12). There was no marked heterogeneity of risk ratios between these studies (P = 0.10). We found no significantly increased risks after ICSI for any of the categories cardiovascular defects, musculoskeletal defects, hypospadias, neural tube defects, or oral clefts.

CONCLUSIONS

Our analysis does not indicate that the ICSI-procedure represents significant additional risks of major birth defects in addition to the risk involved in standard IVF. The data was limited, particularly on risks of specific categories of defects.

Pregnancy outcome of in vitro fertilization/intracytoplasmic sperm injection with profound teratospermia

OBJECTIVE

To assess the pregnancy outcome of IVF with intracytoplasmic sperm injection (ICSI) in couples with profound teratospermia (Kruger's strict criteria of zero).

DESIGN

Retrospective analysis of 545 consecutive cycles of IVF/ICSI performed between January 2000 and January 2003.

SETTING

Tertiary care center.

PATIENT(S)

Of 545 IVF/ICSI cycles, 45 patients were identified with a semen strict morphology of 0 using Kruger's strict criteria.

INTERVENTION(S)

Ovarian down-regulation (Lupron) was followed by controlled ovarian stimulation exclusively with hMG. Embryo transfer was performed 2 days after transvaginal aspiration/ICSI.

MAIN OUTCOMES MEASURE(S)

Pregnancy outcomes and newborn/infant status.

RESULT(S)

Of 45 patients undergoing 54 treatment cycles, 21 patients were positive for pregnancy (38.9% pregnancy/cycle). No birth defects were noted at time of delivery and all infants had obtained appropriate developmental milestones at 1 year of age.

CONCLUSION(S)

Men with profound teratospermia (Kruger's strict criteria of zero) may achieve acceptable pregnancy rates after IVF/ICSI thereby alleviating the use of donor sperm in this group. Furthermore, no increased risk of birth defects is apparent in this small series.

Prenatal karyotypes of fetuses conceived by intracytoplasmic sperm injection

OBJECTIVE

To evaluate the rate of chromosomal abnormalities in babies conceived by intracytoplasmic sperm injection (ICSI).

DESIGN

Retrospective case-control analysis.

SETTING

Private IVF center.

PATIENT(S)

One thousand one hundred thirty-six karyotype results obtained from fetuses conceived by ICSI.

INTERVENTION(S)

Amniocentesis and prenatal karyotyping.

MAIN OUTCOME MEASURE(S)

Presence of normal and abnormal chromosomal configurations.

RESULT(S)

Abnormal karyotypes were detected in 17 (1.5%) of 1,136 fetuses. Eight (0.7%) of these were from singleton and nine (0.8%) from twin pregnancies. There was no difference in the autosomal chromosome structure or the number or structure of sex chromosomes in karyotyped fetuses of singleton and twin pregnancies. However, abnormal numbers of autosomal chromosomes were more frequent in singletons (2.3%) than in twins (1.1%). There was also no difference in the frequency of chromosomal aberrations between ICSI groups in which ejaculated spermatozoa (1.9%) and testicular spermatozoa (1.5%) were used. There was no difference in the frequency of chromosomal aberrations between fetuses for whom ICSI was used because of male factors (1.8%) compared with babies for whom ICSI was also the choice of assisted fertilization method for other types of infertility factors (0.9%).

CONCLUSION(S)

Sperm source does not influence the karyotype of babies conceived by ICSI. By comparing our results with previously reported data from natural pregnancies, we show that ICSI babies carry a significantly increased risk of an abnormal karyotype. However, the increased risk is similar among the different infertility groups.

Safety of GnRH agonists and antagonists

The widespread application of protocols using gonadotropin-releasing hormone (GnRH) agonists or antagonists in assisted reproduction treatment has led to an increasing number of pregnancies exposed to these drugs. This issue has raised scepticism as to the safety of these medications, concerning both pregnant women and their offspring. The main parameters that can be studied to ensure the safety of GnRH analogues include: a) systemic and local reactions to the medication; b) incidence of ovarian hyperstimulation syndrome (OHSS); c) direct effect on oocytes and embryos; and d) the health of those children exposed. So far, no systemic side effects and no major local reactions have been reported following the use of GnRH agonists or third-generation antagonists. On the other hand, the incidence of OHSS seems to be higher with GnRH agonist protocols compared to conventional or GnRH antagonist protocols. The recent cloning of the GnRH receptor has led to the demonstration of GnRH receptor gene expression in the human ovary, although the existence of GnRH receptors per se remains controversial. Similarly, the potential direct effect of GnRH analogues on the follicles and oocytes remains a matter of debate. The incidence of miscarriage and the health of children born as a result of in vitro fertilisation (IVF) treatment do not appear to be influenced by the GnRH agonist treatment. This also seems to be the case for the GnRH antagonists, although the available information on this issue is still limited. Therefore, most of the accumulated data concerning the safety of the GnRH analogues are encouraging, and no serious side effects have been reported. On the other hand, as no definite conclusions about the safety of these drugs can be drawn until now, continued assessment of the aforementioned parameters in long-term follow-up studies is recommended.

Is intracytoplasmic sperm injection safe?

OBJECTIVE

To review the pregnancy and birth outcomes of patients undergoing intracytoplasmic sperm injection (ICSI).

DESIGN

Selective review of the literature.

SETTING

Couples undergoing either conventional IVF or ICSI and their resulting offspring.

PATIENT(S)

None.

MAIN OUTCOME MEASURE(S)

None.

INTERVENTION(S)

None.

RESULTS

These observational studies are unfortunately inherently biased. Regardless, the information and experiences from these large centers cannot be ignored. These experiences reveal that birth weight may be decreased by an amount that is generally not clinically relevant. Chromosomal and genetic abnormalities are increased probably only as a direct corollary to the underlying parental risk. Congenital malformations reveal no clustering of any single specific abnormality. Developmental assessment is available for up to 2 years, and no major delays have been identified in either motor or mental function.

CONCLUSION(S)

Intracytoplasmic sperm injection appears to be a safe alternative for couples who otherwise would be unable to achieve pregnancy. The inherent risks associated with these genetically "at risk" couples mandate thorough evaluation and counseling before undertaking ICSI.

High sex chromosome aneuploidy and diploidy rate of epididymal spermatozoa in obstructive azoospermic men

PURPOSE

To evaluate the frequencies of sex chromosome aneuploidy and diploidy rate of epididymal spermatozoa from obstructive azoospermic men and its impact on intracytoplasmic sperm injection (ICSI) outcomes.

METHODS

Epididymal spermatozoa retrieved from 24 obstructive azoospermic men and ejaculated spermatozoa from 24 fertile donors were analyzed using triple color fluorescence in situ hybridization (FISH) techniques, in order to investigate the rates of diploidy and aneuploidy for chromosomes 18, X and Y.

RESULTS

Epididymal spermatozoa from obstructive azoospermic men had total sex aneuploidy, disomy 18, and diploidy rates significantly higher than ejaculated spermatozoa from normozoospermic fertile controls (1.44% vs 0.14%, 0.11% vs 0.02%, and 0.18% vs 0.02%, respectively; p < 0.005). There were no statistically significant differences in ICSI outcomes between the patients who had high and low epididymal sperm aneuploidy rate.

CONCLUSIONS

Epididymal spermatozoa from obstructive azoospermic patients had an elevated sex chromosome aneuploidy and diploidy rate. The increased frequency of chromosomal abnormalities did not have a direct effect on the ICSI outcome.

ICSI: a technique too far?

Even now 10 years after its introduction, there is still debate on the possible adverse effects of intracytoplasmic sperm injection (ICSI). ICSI has raised a lot of concerns because of the mechanical perforation of the oocyte, the possible transmission of foreign genetic material, the use of immature or senescent germ cells and the association between genetic disorders and some forms of male infertility. To date, the data available indicate that ICSI is a safe procedure provided this treatment is performed in clinics with the highest standards of expertise and with a continuous follow-up programme for the offspring. It is becoming increasingly apparent that it is not ICSI itself, but the background risks of the ICSI patients that represent the major risk factor with regard to congenital malformations. More sex-chromosome abnormalities have been reported in ICSI offspring. Again, the risk of aneuploidy in ICSI progeny reflects the higher aneuploidy rate in the sperm of ICSI fathers. Whether ICSI will eventually perpetuate male infertility is far from clear, because at present the inheritance pattern of idiopathic male infertility is unknown. All ICSI candidates should nevertheless be thoroughly screened and counselled. As long as follow-up studies have a limited power to detect small increases in malformations and as long as no information is available on long-term and next-generation cohorts, ICSI must be used with caution and only when no alternative evidence-based therapy is available. All ICSI candidates should be rigorously screened and thoroughly informed of the limitations of current screening methods and our limited knowledge of the genetic background to male infertility. They should be told that there might be a slight increase in congenital malformation rate after ICSI, but that this increase is probably the result of their own 'background risk'. Well-informed patients are in the best position to judge whether the concerns outweigh the benefits of ICSI.

A benefit-risk assessment of medical treatment for uterine leiomyomas

The growth of a uterine leiomyoma growth stops and regresses after the menopause suggesting that leiomyoma growth is dependent on ovarian steroids. Therefore, estrogen has received much attention as the major factor responsible for the development of uterine leiomyomas, but progesterone also plays an important role in development of this disease. Cytogenetic analyses of resected samples has revealed that about 40 to 50% of leiomyomas show karyotypically detectable chromosomal abnormalities. Gonadotrophin releasing hormone (GnRH) agonists exert their action through the suppression of endogenous gonadotrophins and gonadal steroid secretion. Significant reductions of uterine/leiomyoma volume under GnRH agonist therapy has been reported in several studies. However, the leiomyoma generally returns to its pretreatment volume within a few months after discontinuation of the GnRH agonist. To minimise the adverse effects of hypoestrogenism during GnRH agonist treatment, add back therapy can be used (estrogen-progestin, progestin alone and recently tibolone). Antiprogestins have a potential clinical utility in uterine leiomyomas. Mifepristone is a synthetic steroid with both antiprogesterone and antiglucocorticoid activities, that may have an inhibitory effect on growth of leiomyoma. Danazol is an isoxazole of 17beta-ethinyl testosterone, a synthetic steroid, which has a suppressive effect on sex hormone binding globulin concentrations, resulting in efficacy in the short-term treatment of uterine leiomyomas. Gestrinone is a tri-enic steroid with antiestrogen and antiprogesterone properties and has been shown to reduce uterine volume and stop bleeding. Growth factors play a relevant role on the pathophysiology of uterine leiomyoma and probably the inhibition of the action of growth factors on the myometrium will be the basis for future therapy. A number of agents are under investigation for treating uterine leiomyoma. Agents developed from increasing genetic knowledge of this condition could represent, in the next few years, new trends in the medical treatment of uterine leiomyomas.

Current and future genetic screening for male infertility

Although much of male infertility is currently unexplained, it is likely that underlying defects in critical genes or entire gene pathways are responsible. Because powerful technologies exist to bypass severe male-factor infertility, improving the diagnosis of genetic infertility is important for the infertile couple, not only to explain the problem but also to inform them of conditions potentially transmissible to offspring.

Guidelines for the appropriate use of genetic tests in infertile couples

Research on genetic causes of male and female infertility rapidly expanded in the last years, following the development of in vitro fertilising techniques. Genetic tests are now available to explore the cause of the infertility and assess the risk of a given couple to transmit its genetic characteristics. This allows at-risk couples to take an informed decision when electing for a medically assisted reproduction. It also allows the professionals to offer a prenatal diagnosis when appropriate. Thus, the genetic work-up of the infertile couple has become good practice for an appropriate diagnosis, treatment and prognostic assessment. The lack of national or international rules for the genetic approach to the infertile couple, prompted the Italian community of professionals in the field of reproductive medicine to join and set up guidelines for the genetic diagnosis of male and female infertility. The group of clinical and research experts is representative of 12 national scientific societies and was supported by external experts from four international societies. We examine the clinically relevant genetic causes of male and female infertility and suggest the category of patients for which each genetic test is recommended or optional, both for an accurate diagnosis and prior to ART.

Neonatal data on a cohort of 2889 infants born after ICSI (1991-1999) and of 2995 infants born after IVF (1983-1999)

BACKGROUND

To evaluate the safety of ICSI, this study compared data of IVF and ICSI children by collecting data on neonatal outcome and congenital malformations during pregnancy and at birth.

METHODS

The follow-up study included agreement to genetic counselling and eventual prenatal diagnosis, followed by a physical examination of the children after 2 months, after 1 year and after 2 years. 2840 ICSI children (1991-1999) and 2955 IVF children (1983-1999) were liveborn after replacement of fresh embryos. ICSI was carried out using ejaculated, epididymal or testicular sperm.

RESULTS

In the two cohorts, similar rates of multiple pregnancies were observed. ICSI and IVF maternal characteristics were comparable for medication taken during pregnancy, pregnancy duration and maternal educational level, whereas maternal age was higher in ICSI and a higher percentage of first pregnancies and first children born was observed in the ICSI mothers. Birthweight, number of neonatal complications, low birthweight, stillbirth rate and perinatal death rate were compared between the ICSI and the IVF groups and were similar for ICSI and IVF. Prematurity was slightly higher in the ICSI children (31.8%) than in the IVF children (29.3%). Very low birthweight was higher in the IVF pregnancies (5.7%) compared with ICSI pregnancies (4.4%). Major malformations (defined as those causing functional impairment or requiring surgical correction), were observed at birth in 3.4% of the ICSI liveborn children and in 3.8% of the IVF children (P = 0.538). Malformation rate in ICSI was not related to sperm origin or sperm quality. The number of stillbirths (born > or =20 weeks of pregnancy) was 1.69% in the ICSI group and 1.31% in the IVF group. Total malformation rate taking into account major malformations in stillborns, in terminations and in liveborns was 4.2% in ICSI and 4.6% in IVF (P = 0.482).

CONCLUSIONS

The comparison of ICSI and IVF children taking part in an identical follow-up study did not show any increased risk of major malformations and neonatal complications in the ICSI group.

Should ICSI be the treatment of choice for all cases of in-vitro conception? Considerations of fertilization and embryo development, cost effectiveness and safety

There is now considerable discussion whether intracytoplasmic sperm injection (ICSI) should be used in all cases of IVF. A critical and balanced view of the current literature is presented. The difficult question is how to identify men with apparently normal semen who are likely to fail to achieve a pregnancy using IVF. In conclusion, from both the safety and scientific viewpoint, ICSI should only be used in cases where success at IVF is regarded as unlikely.

Is intracytoplasmic sperm injection safe? Current status and future concerns

In vitro fertilization with intracytoplasmic sperm injection (ICSI) has revolutionized the treatment of patients with severe forms of male infertility. However, because ICSI has been performed for only 10 years, long-term outcomes and risks to offspring remain largely unknown. The fact that ICSI can potentially bypass natural selection barriers to genetic disease transmission has brought a sobering but important impetus to recent research on the risks and outcomes of ICSI. Several studies were done recently to examine specific risks to children born following ICSI. Because of rapid advances in the ICSI procedure itself, studies evaluating the safety of using immature sperm forms from the testis (spermatids, spermatocytes) also have been undertaken. This review summarizes recent studies examining the risks and long-term outcomes to date of in vitro fertilization with ICSI.

A prospective controlled study of karyotyping for 430 consecutive babies conceived through intracytoplasmic sperm injection

OBJECTIVE

To compare the karyotype of babies conceived through ICSI with that of naturally conceived babies.

DESIGN

Prospective controlled study.

SETTING

The Egyptian IVF-ET Center, Cairo, Egypt.

PATIENT(S)

Four hundred and thirty babies conceived through ICSI and 430 babies conceived naturally.

INTERVENTION(S)

ICSI and karyotyping.

MAIN OUTCOME MEASURE(S)

Abnormal karyotype.

RESULT(S)

Four hundred and thirty consecutive babies conceived through ICSI who were delivered in one hospital had 15 abnormal karyotypes (3.5%). Of the 15 babies, 7 were of female phenotype and 8 of male phenotype. Six babies had sex chromosome anomalies, 8 had autosomal anomalies, and 1 had combined sex chromosome and autosomal anomalies. A control group of 430 consecutive babies conceived naturally who were delivered in one hospital had no abnormal karyotype. The difference between the two groups was significant (P<.001).

CONCLUSION(S)

ICSI carries a small but significant increased risk of abnormal karyotyping to the offspring. This risk appears to be equally distributed between autosomal and sex chromosome anomalies.

Outcome in the second year of life after in-vitro fertilisation by intracytoplasmic sperm injection: a UK case-control study

BACKGROUND

There have been reports suggesting that children born after in-vitro fertilisation by intracytoplasmic sperm injection (ICSI) are at increased risk of neurodevelopmental delay. We have undertaken a case-control study of this issue.

METHODS

We studied 208 singleton children conceived by ICSI and a control group of 221 normally conceived singleton children. Children were recruited from 22 fertility centres and local nurseries throughout the UK. Controls were selected to match cases as closely as possible for social class, maternal educational attainment, region, sex, and race. The primary outcome measure was neurodevelopmental scoring; secondary measures were perinatal outcomes, postnatal health, and congenital abnormalities. A single examiner assessed all the children.

FINDINGS

A follow-up rate of 90% for the ICSI group was achieved at a mean age of 17 months. No difference between the study children and controls was found in mean neurodevelopmental scores (98.08 [SD 10.93] vs 98.69 [9.99]) or any subscales on the Griffiths' scales of mental development. Perinatal outcome was similar apart from a higher rate of caesarean section (73 [35.1%] vs 53 [24.0%], p=0.015) and a lower mean birthweight (3163 [SD 642] vs 3341 [606] g, p=0.013) in the study group. Rates of major congenital abnormality were also similar overall (ten [4.8%] study vs ten [4.5%] control), although there were significantly more congenital anomalies among children born to fathers with oligozoospermia than in other children.

INTERPRETATION

This population study did not show any significant difference between children conceived after ICSI and their naturally conceived peers in terms of physical health and development.

ICSI choreography: fate of sperm structures after monospermic rhesus ICSI and first cell cycle implications

We have dissected the initial stages of fertilization by intracytoplasmic sperm injection of single spermatozoa into prime oocytes from fertile rhesus monkeys (Macaca mulatta). DNA decondensation was delayed at the apical portion of the sperm head. It is possible that this asynchronous male DNA decondensation could be related to the persistence of the sperm acrosome and perinuclear theca after injection. However, incomplete male pronuclear formation did not prevent sperm aster formation, microtubule nucleation and pronuclear apposition. In contrast, DNA synthesis was delayed in both pronuclei until the sperm chromatin fully decondensed, indicating that male pronuclear formation constitutes an important checkpoint during the first embryonic cell cycle.