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G D Palermo

Publications and source records attributed to G D Palermo.

At least 37 records · Page 2Linked to original sources
PubMed1999

The role of structural integrity of the fertilising spermatozoon in early human embryogenesis.

While the fertilising spermatozoon supplies the active centre directing the human zygote's first mitotic division, the relative contributions of the sperm head and tail (as well as the importance of the sperm's general structural integrity) to subsequent developmental processes remain incompletely studied. The sperm nucleus contains paternal chromatin necessary for restoration of a diploid genome, but the functional role of the sperm tail (either attached or dissected) in early human embryonic growth is not known. In this investigation using oocytes donated by in vitro fertilisation patients, human oocytes were injected with isolated sperm heads (n = 73), isolated sperm flagella (n = 11) or both (dissected sperm heads + free sperm tails, n = 26). The formation of bipronucleate zygotes was recorded for each method. Among oocytes surviving injection with isolated sperm heads, 44 of 66 (67%) formed two pronuclei. Of oocytes receiving only sperm tails, 2 of 11 (18%) displayed two pronuclei, but a single polar body was evident in both cases. When dissected spermatozoa parts (head + tail) were jointly injected, 12 of 26 (46%) developed two pronuclei. From embryos resulting from each of these three fertilisation regimes, blastomere biopsies were obtained and subjected to multiprobe fluorescent in situ hybridisation (FISH) analysis to detect mosaicism or aneuploidy arising from these experimental treatments. Only embryos with growth sufficient to permit sampling of at least two blastomeres were evaluated, and FISH analysis was successful in 25 of 29 (86%) embryos tested. Of 12 embryos derived from injection of an isolated sperm head, only one was normal diploid; the remaining 11 were mosaic. Both embryos resulting from injection of an unattached sperm tail were mosaic. Of 11 embryos generated from oocyte injection with sperm head + tail segments, 10 (91%) were mosaic and only one was normal diploid. Results from this study show that injection of isolated sperm segments can permit oocyte activation and bipronuclear formation. However, a high rate of mosaicism in human embryos originating from disrupted sperm or sperm components suggests that more than a 'sum of parts' is needed for later development. The structural integrity of the intact fertilising spermatozoon appears to contribute to normal human early embryogenesis.

Blastomeres↗
PubMed1999

Fertilization and pregnancy outcome with intracytoplasmic sperm injection for azoospermic men.

The evident ability of the intracytoplasmic sperm injection (ICSI) procedure to achieve high fertilization and pregnancy rates regardless of semen characteristics has induced its application with spermatozoa surgically retrieved from azoospermic men. Here, ICSI outcome was analysed in 308 cases according to the cause of azoospermia; four additional cycles were with cases of necrozoospermia. All couples were genetically counselled and appropriately screened. Spermatozoa were retrieved by microsurgical epididymal aspiration or from testicular biopsies. Epididymal obstructions were considered congenital (n = 138) or acquired (n = 103), based on the aetiology. Testicular sperm cases were assessed according to the presence (n = 14) or absence (n = 53) of reproductive tract obstruction. The fertilization rate using fresh or cryopreserved epididymal spermatozoa was 72.4% of 911 eggs for acquired obstructions, and 73.1% of 1524 eggs for congenital cases; with clinical pregnancy rates of 48.5% (50/103) and 61.6% (85/138) respectively. Spermatozoa from testicular biopsies fertilized 57.0% of 533 eggs in non-obstructive cases compared to 80.5% of 118 eggs (P = 0.0001) in obstructive azoospermia. The clinical pregnancy rate was 49.1% (26/53) for non-obstructive cases and 57.1% (8/14) for testicular spermatozoa obtained in obstructive azoospermia, including three established with frozen-thawed testicular spermatozoa. In cases of obstructive azoospermia, fertilization and pregnancy rates with epididymal spermatozoa were higher than those achieved using spermatozoa obtained from the testes of men with non-obstructive azoospermia.

Biopsy↗
PubMed1999

A reliable technique of nuclear transplantation for immature mammalian oocytes.

Transplanting a germinal vesicle (GV) to another enucleated oocyte provides a possible way to avoid age-related aneuploidy in metaphase II (MII) oocytes from older women. This study was conducted to examine the efficiency of each step of nuclear transplantation as reflected in the survival and maturation capacity of immature mouse oocytes subjected to this procedure. GV stage oocytes were retrieved from unstimulated ovaries. A GV removed with a small amount of cytoplasm (karyoplast) was transferred subzonally into a previously enucleated oocyte, which was then exposed to direct current to promote fusion. Such reconstituted oocytes were placed in culture to allow maturation, and some that had extruded a first polar body were fixed and processed for chromosome analysis. Each step of nuclear transplantation - survival, enucleation, grafting, and reconstitution - was successful in >90%, with the overall efficiency of reconstitution being 80%. The observation of normal karyotypes confirmed that the procedure did not increase chromosomal aneuploidy. An electrolytic medium, revealed to be superior for the reconstitution procedure, also allowed haploidization of the transplanted nucleus. These findings suggest that this technique can be applied to study the effects of a 'younger' woman's ooplasm on the disjunction of an 'older' woman's chromosomes during meiosis I.

Aneuploidy↗
PubMed1999

Sperm integrity is critical for normal mitotic division and early embryonic development.

The human zygote relies on the paternal gamete to provide the centrosome component essential for the first mitotic division. It is not known whether normal centrosome function requires an intact spermatozoon, or whether donation of an isolated paternal centrosome component can result in normal zygotes and embryos. To explore this possibility, mature human oocytes were microinjected with either intact or dissected spermatozoa. Fertilization and cleavage rates were documented; nuclear and cytoskeletal changes were observed with fluorescent immunocytochemistry; and chromosomal normality was assessed with fluorescent in-situ hybridization. A pilot study was performed to identify cytoskeletal features suggestive of centrosome function. Unfertilized oocytes and tripronucleate (3PN) zygotes from in-vitro fertilization or intracytoplasmic sperm injection were assessed to confirm the sequence of the landmarks of human fertilization. Oocytes injected with mechanically-dissected spermatozoa appear to be capable of normal pronuclear formation and embryonic cleavage, but do not undergo normal mitotic division. Although decondensed, apposed nuclei are noted in combination with diffuse cytoskeleton assembly, no spindle was detected in any zygote resulting from the injection of a dissected spermatozoon. Analysis of selected embryos resulting from dissected sperm injection revealed chromosomal mosaicism in the majority of specimens. The lack of a bipolar spindle, in combination with chromosomal mosaicism, suggests abnormalities of the mitotic apparatus when sperm integrity is impaired following dissection.

Cell Nucleus↗
PubMed1999

Testicular sperm extraction with intracytoplasmic sperm injection for nonobstructive azoospermia: testicular histology can predict success of sperm retrieval.

PURPOSE: We present treatment results of testicular sperm extraction with intracytoplasmic sperm injection for men with nonobstructive azoospermia and reevaluate the role of testicular histology on open diagnostic testicular biopsy as a predictor of sperm retrieval success. MATERIALS AND METHODS: We evaluated 75 men diagnosed with nonobstructive azoospermia. Cases were categorized into 3 groups of hypospermatogenesis, maturation arrest or Sertoli-cell-only based on the most advanced pattern of spermatogenesis seen on histology. A total of 81 testicular sperm extractions with intracytoplasmic sperm injection were performed for these 75 men. The main outcome measures reviewed included sperm retrieval, fertilization and pregnancy rates with intracytoplasmic sperm injection. Sperm retrieval success rates for men in the 3 histological categories were compared. RESULTS: Spermatozoa were successfully retrieved during 47 of 81 (58%) testicular sperm extraction attempts, with subsequent fertilization of 268 of 439 (61%) injected metaphase II oocytes using intracytoplasmic sperm injection. Clinical pregnancies were obtained in 26 of 47 (55%) cycles when sperm were retrieved, with ongoing pregnancies or live deliveries for 20 of 47 (43%). Of 39 men with hypospermatogenesis on diagnostic biopsy 31 (79%) had successful sperm retrieval, compared to 9 of 19 (47%) with maturation arrest and 5 of 21 (24%) with a pure Sertolicell-only pattern. CONCLUSIONS: Critical examination of the most advanced pattern of spermatogenesis from open diagnostic testis biopsy allows prediction of sperm retrieval success with testicular sperm extraction. In this study population spermatozoa were retrieved in 58% of attempts. When this testicular sperm was used with intracytoplasmic sperm injection, clinical pregnancy rate was 55% for men with nonobstructive azoospermia.

Adult↗
PubMed1999

A comparison of human spermatozoa immunolabeling features using xenogenic reagents for centrosomal proteins.

The centrosome is an organelle essential to proper chromosomal migration and normal cell growth. In the human, the centrosome is comprised of two centrioles and the pericentriolar cytosol; its control of embryo cleavage processes derives from its role as a locus for spindle organisation. At fertilisation, it is the human sperm centrosome that is responsible for ordering these processes, as the oocyte appears not to contain working centrosomal structures. Abnormalities in fertilisation or early embryo cleavage could be related to impaired sperm centrosome structure or function in some cases. While potential future treatments of infertility due to a defective centrosome could involve use of a donor centrosome to restore normal cell development, such an approach would depend on accurate localisation of this organelle for subsequent transplantation. To locate centrosomal components in the heads and tails of human spermatozoa, labeling was performed on intact spermatozoa using antibodies of known specificity to highly-conserved centrosomal elements. Following general mapping of immunofluorescent signals, unlabeled sperm were dissected to form head/tail sperm fragments which were then separately tested. Distribution of centrosomal proteins in head and tail fragments was assayed for each separation method. Three reagents were compared: 1) rabbit anti-mitotic spindle protein (anti-MSP) antibody, 2) rabbit polyclonal centriole-specific antibodies, and 3) mouse monoclonal anti-MPM-2 (a centrosome phospoprotein) antibody. Of these, anti-MPM-2 antibody appeared to be the most reliable, labeling centrosomal elements in 63% (n = 1,386) of treated spermatozoa. Sequential utilization of n-butylamine to effect head/tail separation followed by anti-MPM-2 antibody labeling was a satisfactory method of centrosome localisation. Microextraction of centrosomes and pericentriolar matrix identified by this method awaits further testing.

Affinity Labels↗
PubMed1998

Sex-selection of human spermatozoa: evolution of current techniques and applications.

Methods claiming to achieve sex selection by sperm sorting have existed for many years. Numerous applications for safe and effective selection procedures exist in current clinical practice, as sex-linked conditions could be theoretically eliminated by use of appropriate sperm for fertilization or insemination. Use of such techniques could also address the need to effect family balancing for some couples. Modern preconception sex-selection methods may be classified into two general types: those that attempt to segregate spermatozoa on the basis of subtle physical or kinetic features, and those that rely on distinctive nuclear characteristics unique either to X- or Y-chromosome bearing sperm. Laboratories providing sperm sexing using the former method have been available for some years, although the associated efficiency and reproducibility are controversial. Sex selection of spermatozoa by chromatin differences has been shown to achieve significant enrichment of X- or Y-chromosome bearing sperm, but clinical experience in humans is limited. The fundamental elements of the two approaches introduced here are reviewed and compared. Selected key historical concepts in sex selection by sperm sorting are outlined, followed by a summary of promising areas for future research.

Centrifugation, Density Gradient↗
PubMed1998

AZFb deletions predict the absence of spermatozoa with testicular sperm extraction: preliminary report of a prognostic genetic test.

Genetic abnormalities, including partial deletions of the Y-chromosome, are commonly detectable in men with non-obstructive azoospermia (NOA). NOA can be treated using testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI). Recent studies have shown that the presence of deletions involving the AZFc region do not appear to affect the chance of retrieving spermatozoa or have a significant impact on fertilization or pregnancy rates with ICSI. We investigated the effect of Y-chromosome partial deletions on the chance of sperm retrieval with TESE. Eighty attempts at sperm retrieval were performed using TESE on men who were previously evaluated for Y-chromosome partial deletions. Y-chromosome analysis was performed using a polymerase chain reaction (PCR)-based technique with 35 sequence-tagged-sites. Of the 80 men, nine (11%) had partial Y-chromosome deletions detected. Two azoospermic men with AZFc deletions had successful sperm retrieval, ICSI and a subsequent clinical pregnancy. Seven men had deletions involving the AZFb region (three men had isolated AZFb deletions, one had AZFa, AZFb and AZFc deleted, and three had AZFb and AZFc deleted). None of the seven men had spermatozoa extracted by TESE, a result that is significantly different from the overall 64% (47/73) sperm retrieval rate achieved at our centre (P = 0.001). Two men with AZFb deletions had cells consistent with round spermatids identified and injected into oocytes without effecting any normal fertilizations. Although preliminary, these results suggest that the presence of an AZFb deletion is a significantly adverse prognostic finding for TESE. Men with AZFb deletions should be apprised of these results before attempting TESE-ICSI. Alternatives such as donor insemination or adoption should be considered or therapy delayed until improved results with round spermatid injections are likely.

Adult↗
PubMed1998

Comparison of clinical outcome after cryopreservation of embryos obtained from intracytoplasmic sperm injection and in-vitro fertilization.

The impact of intracytoplasmic sperm injection (ICSI) on cryopreserved zygotes and embryos was evaluated by comparing embryo survival and implantation between embryos derived from ICSI and those derived from standard insemination procedures. The study included patients whose excess zygotes and embryos were cryopreserved between September 1993 and December 1994 and who subsequently underwent a frozen embryo transfer. Embryo survival, clinical pregnancy rates per transfer and pregnancy outcome were compared. Three hundred and thirty eight cryopreservation cycles, during which 1471 embryos were cryopreserved, were included in this study. Of those, 961 were derived from oocytes fertilized by insemination in vitro and 510 were derived from oocytes fertilized by ICSI. A total of 690 of the embryos (451 in the insemination group and 239 in the ICSI group) have since undergone a thaw cycle. The embryo survival rates were similar between the two groups (70.5 and 73.2%, insemination and ICSI respectively) and were not significantly affected by the stage at cryopreservation. There was no significant difference in pregnancy rates per transfer (31.8 and 32.3%), the preclinical pregnancy loss rate (16.7 and 23.8%), or the clinical miscarriage rate (16.7 and 23.8%) between the insemination and the ICSI groups respectively. It is concluded that ICSI does not have an adverse impact on the survival and successful implantation of cryopreserved and thawed embryos.

Cryopreservation↗
PubMed1998

Effect of parental age on fertilization and pregnancy characteristics in couples treated by intracytoplasmic sperm injection.

The purpose of this study was to investigate any influence of maternal and/or paternal age on gamete characteristics and pregnancy outcomes in intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive ICSI cases were analysed retrospectively. While a significant linear decline in semen volume was detected, no significant differences in the concentration, motility or morphology of the spermatozoa were found with paternal ageing. A significant decline in the number of oocytes retrieved and the number of mature oocytes obtained was found with advancing maternal age. An increase in the occurrence of digyny was noted with parental ageing, while no difference in single or bipronuclear fertilization was found. Older women had a decreased incidence of single pronucleus formation and an increase in digyny, but no significant difference in the percentage of oocytes that underwent two-pronuclear fertilization was detected with regard to maternal ageing. Pregnancy outcomes were not influenced by the age of the male partner, while a strong negative correlation was found with maternal ageing. To better analyse male partner ageing as a factor affecting pregnancy outcome, we analysed a subgroup of patients with a female partner aged <35 years who underwent ICSI. No paternal influence on ICSI pregnancy outcome was found in this subgroup of patients. We conclude that the influence on pregnancy outcome after ICSI is related mostly to maternal and not paternal age.

Adult↗
PubMed1998

Implications of complete fertilization failure after intracytoplasmic sperm injection for subsequent fertilization and reproductive outcome.

With the introduction of intracytoplasmic sperm injection (ICSI), couples with severe male factor infertility have achieved fertilization and clinical pregnancy rates comparable to other in-vitro fertilization (IVF) patients. However, failure of fertilization still occurs in some patients despite the utilization of microsurgical sperm injection techniques. How such fertilization failure after ICSI might impact later ICSI treatment(s) is unknown. In this investigation, couples with complete fertilization failure after ICSI treated from August 1993 to August 1996 were identified (index cycle, n = 21). Additionally, fertilization data from any previous or subsequent infertility treatments were evaluated. Seven patients (33%) had at least one IVF treatment before the index cycle, although no deliveries occurred. Of patients with complete fertilization failure in the index cycle, 48% (n = 10) underwent at least one subsequent ICSI cycle which proceeded to oocyte retrieval. The remainder (n = 11) elected to discontinue treatment. Although six subsequent cycles were cancelled due to poor follicular response (< or = 2 mature oocytes), all patients electing to continue treatment eventually achieved a subsequent embryo transfer. The clinical pregnancy rate per transfer was 45.4% for this group; the delivery and ongoing pregnancy rate per transfer was 36.3%. Review of semen parameters, superovulation characteristics or other clinical parameters during the three study cycles (pre-index, index, and post-index) was not prognostic of fertilization success or reproductive outcomes in later treatments. Fertilization failure with ICSI therefore could not be predicted by prior cycle performance, although total immotility of spermatozoa at time of oocyte retrieval, total teratozoospermia, and low oocyte yield were common characteristics of couples experiencing complete fertilization failure with ICSI. These findings suggest that fertilization failure in one ICSI cycle does not preclude successful fertilization and delivery in a later ICSI treatment.

Counseling↗
PubMed1998

H-Y antigen expression patterns in human X- and Y-chromosome-bearing spermatozoa.

PROBLEM: Restricted expression of H-Y antigen on Y-chromosome-bearing sperm has been reported in some species, although such preferential expression for H-Y antigen in human sperm has yet to be described. In this study, an immunomagnetic approach was used to characterize antigen expression patterns as a function of sex-chromosome content. METHOD OF STUDY: Human sperm was treated with monoclonal immunoglobulin (Ig) M antibodies directed against H-Y antigen. This preparation then was incubated with sheep antimouse IgM antibody affixed to paramagnetic beads, which then were exposed to a magnetic field and sorted. X- and Y-chromosome frequencies in the two subgroups of sperm were assayed by multiprobe fluorescent in situ hybridization (FISH). RESULTS: Sperm were immunomagnetically separated into two populations: a reactive group (presumably, H-Y Ag+); and a nonreactive group (presumably, H-Y Ag-). Triple-color FISH analysis of 1,600 spermatozoa (800 in each group) showed the antigen's expression to be somewhat more prevalent among Y-chromosome-bearing sperm (54.1%), but a large proportion of Y-chromosome-bearing sperm (49.0%) did not express this antigen. The difference was not significant (P = 0.43). CONCLUSIONS: The expression of H-Y antigen has a slightly higher frequency in human sperm containing the Y-chromosome, but its expression among X-chromosome-bearing sperm also is considerable. Current immunologic techniques relying on this antigen are unlikely to effect the sex selection of human sperm.

Animals↗
PubMed1997

Testicular sperm extraction with intracytoplasmic sperm injection for nonobstructive azoospermia.

OBJECTIVES: To provide fertility for men with nonobstructive azoospermia. METHODS: A retrospective review of treatment results at a university infertility center was undertaken. Sixteen couples entered an attempted in vitro fertilization (IVF)-intracytoplasmic sperm injection (ICSI) cycle for treatment of nonobstructive azoospermia. Each man was azoospermic, and the male factor diagnosis of nonobstructive azoospermia was made on testis biopsy for 14 men and on clinical grounds for 2 men. Sperm were retrieved by testicular biopsy on the day of oocyte retrieval. Results of testicular examinations, serum follicle-stimulating hormone levels, and testicular histology as well as evaluation of the success rates of sperm retrieval, fertilizations, and pregnancies were made. RESULTS: Sperm were extracted from testis biopsies in 10 of 16 (62%) testicular sperm extraction (TESE) attempts. For cycles in which sperm were retrieved, normal fertilizations were achieved for 51 of 98 (52%) mature oocytes injected with testicular sperm in 10 couples. Biochemical pregnancies were achieved for 6 of 16 (38%) couples, with clinical pregnancies during 5 of 16 (31%) attempts at sperm retrieval, and ongoing pregnancy and subsequent live delivery for 4 of 16 (25%) attempts. CONCLUSIONS; Pretreatment clinical parameters are unable to predict which men with nonobstructive azoospermia will have spermatozoa retrieved by TESE. When sperm are found, clinical pregnancies can occur for half (5/10) of these couples using TESE with ICSI, with ongoing pregnancy and delivery for 4 of 10 (40%). Many men with nonobstructive azoospermia will have retrievable sperm with testis biopsy that are suitable for ICSI; however, 6 of 16 (38%) couples will not have sperm retrieved with TESE and may undergo an unnecessary IVF procedure.

Adult↗
PubMed1997

Human sperm cytosolic factor triggers Ca2+ oscillations and overcomes activation failure of mammalian oocytes.

Among the possible mechanisms of oocyte activation after sperm penetration, it appears most likely that a protein released by the spermatozoon elicits a calcium elevation in the ooplasm. To further test this idea, cytosolic factors obtained from human spermatozoa by two different methods, freezing-thawing and sonication, were injected into mouse oocytes following which intracellular calcium release was measured. Of a total of 42 mouse oocytes, a pattern of calcium oscillations was observed in nine out of 16 oocytes injected with sonicated fraction, in all of eight oocytes with the frozen-thawed fraction and in none of 18 control oocytes. Injection of the frozen-thawed fraction also produced regular calcium oscillations in all of five in-vitro matured human oocytes. To assess the putative factor's ability to support fertilization, human oocytes that were not activated by prior intracytoplasmic injection of spermatozoa (ICSI) and round spermatids were reinjected with the frozen-thawed sperm fraction. Of 23 human oocytes which remained unfertilized after ICSI, 19 became activated after injection with sperm cytosolic factor; eight showed two pronuclei, three one pronucleus and eight showed three or more pronuclei. Of 11 oocytes unfertilized after prior round spermatid injection, two developed two pronuclei, four developed one pronucleus and two had three or more pronuclei. Cytogenetic analysis by fluorescence in-situ hybridization confirmed the existence of a male pronucleus in eight out of nine such zygotes displaying two or more pronuclei. Thus, human sperm extracts activated mouse and human oocytes after injection, as judged by calcium flux patterns in conjunction with male pronucleus formation.

Animals↗
PubMed1997

The human sperm centrosome is responsible for normal syngamy and early embryonic development.

As early as 1887, it was postulated that the mature oocyte possesses all of the elements necessary for embryonic development with the exception of an active division centre, and that the spermatozoon contains such a centre, but lacks the substrate in which to operate. This division centre is called the centrosome. The precise definition of this structure is still a subject for debate. It consists of two centrioles in a perpendicular arrangement and pericentriolar material, and is considered to be responsible for nucleation of microtubules and the formation of the mitotic spindle. There is a paternal pattern of inheritance of the centrosome in humans; thus, human oocytes lack centrioles but the spermatozoa carry two. At gamete fusion the sperm tail is incorporated into the ooplasm, and the centriolar region forms the sperm aster while the sperm head is decondensing; this aster acts to guide the female pronucleus towards the male pronucleus. The centriole duplicates during the pronuclear stage, and at syngamy centrioles are found at opposite poles of the first cleavage. The centrosome has several implications for human infertility. It is possible that immotile or nonprogressively motile spermatozoa may possess centriolar abnormalities or an absence of centrioles. Similarly, antisperm antibodies against centrioles may be responsible for mitotic arrest. One way of solving this problem would be the use of donor centrosomes. To this end, we have assessed the ability of embryos injected with physically separated sperm segments (head only, head and tail separated or isolated tail) to develop normally. Fluorescent in situ hybridization revealed an almost universal mosaicism in these embryos, suggesting that physical disruption of the spermatozoa compromises the ability of the centrosome to function in the zygote. Thus far, centrosome donation with centriole-carrier flagellae obtained by this dissection method does not appear to be feasible.

Cell Cycle↗
PubMed1996

Evolution of pregnancies and initial follow-up of newborns delivered after intracytoplasmic sperm injection.

OBJECTIVE: To analyze the in vivo development of embryos conceived after intracytoplasmic sperm injection (ICSI), as well as obstetric outcome, occurrence of chromosomal abnormalities, and rate of congenital malformations in neonates born as a result of this treatment. DESIGN: Retrospective study. SETTING: University-based in vitro fertilization (IVF) clinic. PATIENTS: A total of 751 couples in whom the male partners were presumed to be the cause of repeated failed IVF attempts or whose semen parameters were unacceptable for conventional IVF treatment. INTERVENTIONS: Analysis of pregnancies resulting from 987 ICSI cycles; pregnancy outcome data were obtained from the records of obstetrician-gynecologists and/or pediatricians. MAIN OUTCOME MEASURES: Pregnancy rates, obstetric outcome, and frequency of chromosomal abnormalities and congenital malformations. RESULTS: The overall clinical pregnancy (fetal heartbeat) rate was 44.3%, with a resultant delivery rate per ICSI cycle of 38.7% (n=382). In 8 of 11 miscarriages for which cytogenetic data were available, an autosomal trisomy was found, and 7 additional pregnancies were terminated because of a chromosomal abnormality after prenatal diagnosis. There was an equal distribution of vaginal vs cesarean deliveries (n=192 and n=190, respectively). Of the 578 neonates resulting from treatment by ICSI, 15 (2.6%) presented with congenital abnormalities (9 major and 6 minor abnormalities). However, this frequency of malformations is lower than that observed in offspring born after standard IVF at our institution. Furthermore, when pregnancy outcome of ICSI vs IVF was analyzed in terms of semen origin, no differences were found in the frequency of miscarriages or in the rate of congenital malformations. CONCLUSIONS: The evolution of pregnancies and occurrence of congenital malformations following treatment by ICSI were within the range observed with standard in vitro fertilization.

Adult↗