Intracytoplasmic sperm injection: what are the risks?

A multi-centre cohort study of the physical health of 5-year-old children conceived after intracytoplasmic sperm injection, in vitro fertilization and natural conception

BACKGROUND

Over a million children have been born from assisted conception worldwide. Newer techniques being introduced appear less and less 'natural', such as intracytoplasmic sperm injection (ICSI), but there is little information on these children beyond the neonatal period.

METHODS

540 ICSI conceived 5-year-old children from five European countries were comprehensively assessed, along with 538 matched naturally conceived children and 437 children conceived with standard IVF.

RESULTS

Of the 540 ICSI children examined, 63 (4.2%) had experienced a major congenital malformation. Compared with naturally conceived children, the odds of a major malformation were 2.77 (95% CI 1.41-5.46) for ICSI children and 1.80 (95% CI 0.85-3.81) for IVF children; these estimates were little affected by adjustment for socio-demographic factors. The higher rate observed in the ICSI group was due partially to an excess of malformations in the (boys') urogenital system. In addition, ICSI and IVF children were more likely than naturally conceived children to have had a significant childhood illness, to have had a surgical operation, to require medical therapy and to be admitted to hospital. A detailed physical examination revealed no further substantial differences between the groups, however.

CONCLUSIONS

Singleton ICSI and IVF 5-year-olds are more likely to need health care resources than naturally conceived children. Assessment of singleton ICSI and IVF children at 5 years of age was generally reassuring, however, we found that ICSI children presented with more major congenital malformations and both ICSI and IVF children were more likely to need health care resources than naturally conceived children. Ongoing monitoring of these children is therefore required.

Increased sperm nuclear DNA damage in normozoospermic infertile men: a prospective study

OBJECTIVE

To evaluate levels of sperm nuclear DNA damage in infertile men with normal and abnormal standard semen parameters.

DESIGN

Prospective study.

SETTING

Male infertility clinic.

PATIENT(S)

Ninety-two men seeking infertility treatment and 16 fertile volunteers.

INTERVENTION(S)

Standard semen analysis was performed according to the World Health Organization guidelines.

MAIN OUTCOME MEASURE(S)

Sperm DNA damage was assessed by sperm chromatin structure assay and the results expressed as %DFI.

RESULT(S)

Of the 92 patients, 21 (23%) had normal standard sperm parameters (concentration, motility, and normal sperm forms), while 71 (77%) had an abnormality in one or more of these parameters. The %DFI [median (25th and 75th percentiles)] in infertile men with normal sperm parameters [23 (15, 32)] was significantly higher than fertile donors [15 (11, 20)] (P=.02), but not significantly different from infertile men with abnormal sperm parameters [28 (18, 41)] (P=.27).

CONCLUSION(S)

The results of this study indicate that a significant increase in SCSA-defined DNA damage can be found in sperm from infertile men with normal standard sperm parameters. Therefore, sperm DNA damage analysis may reveal a hidden abnormality of sperm DNA in infertile men classified as idiopathic based on apparently normal standard sperm parameters.

The rate of aneuploidy is altered in spermatids from infertile mice

BACKGROUND

It is now possible for infertile males to father their own genetic children through the technique of ICSI. This prospect has consequently prompted several investigations into the quality of sperm being retrieved from infertile males. One potential risk is the use of aneuploid sperm or spermatids, which might then be transferred to the fertilized oocyte.

METHODS

In this investigation, aneuploidy of spermatids was assessed through immunocytochemistry using antibodies directed against chromosome centromeric regions and complexes. Three different types of infertile male mice with phenotypes closely resembling those described in human non-obstructive azoospermia [PP1cgamma-deficient mice, CREM-deficient mice and C57BL/6J.MAC-17(0--23) mice] were examined for chromosome numbers by counting the number of kinetochores in round spermatids using a CREST antiserum.

RESULTS

PP1cgamma(-/-) and CREM(-/-) spermatids from infertile mice showed highly significant elevated levels in the rate of aneuploidy compared with wild-type animals (P < 0.0001). Thus infertile males with independent genetic mutations resulting in different histopathologies showed a high risk in the level of aneuploidy in their spermatids.

CONCLUSIONS

These results suggest that impaired spermatogenesis may lead to production of aneuploid gametes. Analysis of aneuploidy in gametes from infertile men, coupled with appropriate genetic counselling, is recommended prior to ICSI.

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.