Is intracytoplasmic sperm injection (ICSI) a safe procedure? What do we learn from early pregnancy data about ICSI?

Blastocyst formation in in vitro fertilization versus intracytoplasmic sperm injection cycles: influence of the fertilization procedure

OBJECTIVE

To compare the quality of early cleaving embryos and blastocysts obtained by IVF or intracytoplasmic sperm injection (ICSI).

DESIGN

Retrospective study.

SETTING

Tertiary infertility center.

PATIENT(S)

Sibling oocytes of 104 patients in 104 IVF vs. ICSI cycles.

INTERVENTION(S)

Cumulus oocyte complexes (n = 1,358) were randomly subjected to ICSI or IVF.

MAIN OUTCOME MEASURE(S)

Embryo development and blastocyst formation rate. The blastocyst quality and cycle efficiency were also evaluated.

RESULT(S)

Early embryo cleavage was higher after ICSI (37.1%) compared to IVF (14.1%). The percentage of > or =4-cell embryos on day 2 and > or =8-cell embryos on day 3 was similar for both procedures. The overall blastocyst formation was not different between ICSI (50.2%) and IVF (54.8%), neither was the percentage of good-quality blastocysts (31.3% for ICSI and 36.0% for IVF). The total cycle efficiency (percentage of embryos transferred and frozen per two pronuclei [2PN]) was comparable for the two techniques (51.7% for ICSI and 57.4% for IVF).

CONCLUSION(S)

No differences were found on sibling oocytes in the embryo development and blastocyst formation, irrespective of the fertilization procedure. Earlier suggestions that the ICSI technique may result in impaired blastocyst development were not confirmed in this study.

Should ICSI be used in non-male factor infertility?

There is general agreement that intracytoplasmic sperm injection (ICSI) should be used in male factor infertility cases, such as oligoasthenoteratozoospermia, presence of anti-sperm antibodies, or azoospermia, these cases being diagnosed through abnormal semen analysis. There are no randomized clinical trials comparing ICSI with IVF (or other interventions) where semen quality is so poor that IVF would not achieve fertilization. It is accepted that ICSI is the only treatment option in those circumstances. The role of ICSI where IVF can be expected to give a reasonable fertilization rate is the question that needs to be answered. The argument is whether or not ICSI should be used for all cases of infertility. This paper proposes and strongly supports the use of ICSI for all indications. Considerations of fertilization and embryo development, cost effectiveness and safety will be clearly discussed.

Obesity increases the risk of spontaneous abortion during infertility treatment

OBJECTIVE

This study examines the relationship between body mass and the risk of spontaneous abortion in a large cohort of patients who received infertility treatment.

RESEARCH METHODS AND PROCEDURES

This is a retrospective study using data on pregnancies (n = 2349) achieved after treatment in a tertiary medical center from 1987 to 1999. One pregnancy per subject was included, and the subjects were stratified into five body mass groups based on body mass index (BMI): underweight, <18.5 kg/m(2); normal, 18.5 to 24.9 kg/m(2); overweight, 25 to 29.9 kg/m(2); obese, 30 to 34.9 kg/m(2); and very obese, > or =35 kg/m(2). Logistical regression analysis was used.

RESULTS

The overall incidence of spontaneous abortion was 20% (476 of 2349). The effect of BMI on the risk of spontaneous abortion was significant after adjusting for several independent risk factors. Compared with the reference group (BMI 18.5 to 24.9 kg/m(2)), underweight women had a similar risk of spontaneous abortion, whereas there was progressive increase of risk in overweight, obese, and very obese groups (p < 0.05, p < 0.01, and p < 0.001, respectively).

DISCUSSION

Of all known risk factors for spontaneous abortion, the control of obesity has great significance because it is noninvasive, potentially modifiable, possibly amenable to low cost, and self-manageable by patients. This study established a positive relationship between BMI and the risk of spontaneous abortion in women who became pregnant after assisted reproductive technology treatment.

Cumulative pregnancy rate following IVF and intracytoplasmatic sperm injection with ejaculated and testicular spermatozoa

The purpose of this study was to calculate the cumulative pregnancy rates of IVF cycles with ICSI using ejaculated or testicular spermatozoa. A computerized database for the IVF cycles with ICSI performed between January 1996 and December 1998 was utilized. Cycles with spermatozoa obtained after electro-ejaculation were excluded. A multifactorial analysis was performed to define the impact of different factors on the success rate of IVF and ICSI. During a 36-month period, 229 pregnancies were achieved by 643 couples using ejaculated spermatozoa, and 83 pregnancies by 167 couples who required testicular spermatozoa. The pregnancy rates (PR) per cycle, including all treatment cycles with ejaculated spermatozoa, remained similar during the first five consecutive cycles achieving a cumulative PR of 80.44%. The cumulative pregnancy rates for cycles with testicular spermatozoa showed a consistent rise during four consecutive treatments and reached 61.84%. The regression analysis of pregnancy rate showed that it was significantly positively correlated with oocyte fertilization rate (P = 0.02), and negatively correlated with maternal age (P = 0.03). Thus, according to the present results, couples with infertility who require IVF with ICSI should be offered at least five consecutive attempts if ejaculated spermatozoa are used, and at least four cycles whenever testicular spermatozoa are used.

Histological and genetic analysis and risk assessment for chromosomal aberration after ICSI for patients presenting with CBAVD

Intracytoplasmic sperm injection (ICSI) has opened a new field in the treatment of male infertility, leading to a debate concerning its genetic safety. In this study we present an analysis of 11 patients presenting congenital bilateral absence of the vas deferens (CBAVD). In all 11 cases, genetic counselling, histological analysis of testicular biopsies, cystic fibrosis transmembrane conductance regulator (CFTR) mutation screenings of both partners and spermatozoa three-colour fluorescent in-situ hybridization (FISH) analysis were performed. A total of 31 CFTR mutations were screened and mutations were found in eight out of 11 cases, with DeltaF508 being the most common mutation found. Histological analyses showed that seven out of 11 patients had normal tubule/membrane/interstitium (TMI) and Johnsen scores, while the remaining four patients had mild impairment of testicular parenchyma. The average aneuploidy rate was 6.8 +/- 3.9% compared with two control subjects with 4.4 and 5.4% aneuploidy rates respectively, using FISH analysis. After ICSI, the fertilization and pregnancy rates were 66.2 and 22.7% respectively. Thus, in our case of CBAVD, the risk of chromosomal aberration following ICSI, in the absence of a CFTR mutation in the male patient and/or in his partner, was not higher than in normal fertile men. Furthermore, the pregnancy success rate following ICSI of these CBAVD patients was comparable to the general ICSI population, even when histological analysis showed limited spermatogenesis.

Should ICSI be the treatment of choice for all cases of in-vitro conception?

The objective of this study was to examine different clinical scenarios of in-vitro conception, viz. fertilization with conventional IVF, IVF with high insemination concentration (HIC) and intracytoplasmic sperm injection (ICSI), and assess on a sibling oocyte comparison the hypothesis that ICSI should be performed in all cases requiring in-vitro conception. ICSI with husband's spermatozoa had a higher incidence of fertilization as compared with IVF or IVF with HIC with donor spermatozoa (if previous failure of fertilization had occurred) for unexplained infertility. Similarly, ICSI with husband's spermatozoa had as high an incidence of fertilization as IVF with donor spermatozoa for patients with severe oligozoospermia, asthenozoospermia and/or teratozoospermia, even when the spermatozoa were not selected for their morphology. Two studies were performed to assess ICSI in potential oocyte-related failure of IVF, viz. when fertilization occurred in >50% of oocytes for one group of patients, and in <50% of oocytes in a second group. In both of these studies a significant proportion of the oocytes that failed to fertilize with conventional IVF eventually fertilized after ICSI. The overall conclusion was that ICSI as a first option offers a higher incidence of fertilization, maximizes the number of embryos and minimizes the risk of complete failure of fertilization for all cases requiring in-vitro conception. However, among other concerns, current knowledge of ICSI as an outcome procedure does not provide the confidence to use this process in all cases of IVF for the time being.

Short-term medical complications of 1500 oocyte retrievals for in vitro fertilization and embryo transfer

OBJECTIVE

To evaluate the different short-term complications after in vitro fertilization and embryo transfer.

DESIGN

a retrospective study on 7 years in the fertility clinic of an university hospital.

MATERIALS AND METHODS

Short-term medical complications were analysed after 1500 transvaginal ultrasonographically guided oocyte retrievals.

RESULTS

Ovarian hyperstimulation syndrome (1.8%), pelvic infections (0.4%), intraperitoneal bleeding (0.2%) and adnexal torsions (0.13%) were observed. One case of adnexal torsion occurred during pregnancy (0.18%). Two unusual case of bowel endometriosis were encountered (0.13%).

CONCLUSIONS

Short-term medical complications after in vitro fertilization and embryo transfer are rare (2.8%). This contrast with the high rate of multifetal pregnancies which increases maternal and perinatal morbidity and mortality and must be considered as the major complication of in vitro fertilization treatment.

The outcome of clinical pregnancies following intracytoplasmic sperm injection is not affected by semen quality

The objective of this study was to investigate the impact of severe oligoasthenoteratozoospermia (OAT) on pregnancy outcome. For this purpose 279 consecutive intracytoplasmic sperm injection (i.c.s.i) cycles were retrospectively evaluated and compared to 436 consecutive IVF cycles performed during the same time frame. Group A (n = 62) included ICSI patients with severe OAT; group B (n = 217) included patients who underwent ICSI for other indications; and group C (n = 436) included couples who underwent standard IVF. The mean age of female patients and mean number of embryos transferred were comparable in all groups. No difference was observed regarding implantation, clinical pregnancy, delivery and miscarriage rates between all three groups, but fertilization rate was significantly lower in group A than in groups B and C. It is concluded that couples undergoing ICSI with severe male infertility (OAT) have a slightly reduced fertilization rate but their chances of delivery and pregnancy loss are similar to those of other patients undergoing clinical ICSI and IVF with non-male infertility.