Obstetric outcome of 424 pregnancies after intracytoplasmic sperm injection

An evaluation of the outcome of pregnancies resulting from intracytoplasmicsperm injection for severe male factor infertility was conductedby analysing the data obtained from the patients and/or theirobstetrician/gynaecologist on standardized questionnaires. Thedata from 424 pregnancies between April 1991 and September 1994were analysed. Early pregnancy loss before 16 weeks occurredin 99 cases (23.3%), including 48 clinical abortions (11.3%),47subclinical pregnancies (11.1%) and four ectopic pregnancies(0.9%). Vanishing twins and triplets, which could be regardedas early embryonic wastage, were found in 36 cases (8.5%). Onepregnancy was interrupted at week 15 of gestation because ofanhydramnios, and four pregnancies (0.9%) ended in spontaneouslate abortions before 26 weeks. A total of 320 pregnancies (75.5%)resulted in the birth of at least one child; 222 of these (69.3%)were singletons, 93 were twins (29.1%) and five were triplets(1.6%). The problems of prematurity and low birthweight wereespecially related to the multiplicity of pregnancies. Furthermore,from among the total of 423 babies born, we have observed threecases of stillbirth and five cases of neonatal mortality. Theperinatal mortality rate was therefore 18.9 per 1000 births.The results of this study show that the obstetric outcome ofthese pregnancies was similar to that obtained after conventionalin-vitro fertilization and other assisted reproduction techniques.     

High fertilization and pregnancy rate after intracytoplasmic sperm injection with spermatozoa obtained from testicle biopsy

In cases requiring microsurgical epididymal sperm aspiration(MESA) for congenital absence of the vas deferens (CAVD) orirreparable obstructive azoospermia, often no spermatozoa canbe retrieved from the epididymis, or there may even be no epididymispresent. We wished to see whether testicular biopsy with testicularsperm extraction (TESE) in such cases could yield spermatozoathat would result in successful fertilization and pregnancy(despite the absence of epididymal spermatozoa) using intracytoplasmicsperm injection (ICSI). In the same setting during the same2-week period, 28 patients with CAVD or irreparable obstructionwere treated; 16 consecutive fresh MESA—ICSI cycles and12 cycles which required testicular biopsy with testicular spermextraction (TESE—ICSI) were performed. Normal two-pronuclearfertilization rates were similar in both groups: 45% for epididymalspermatozoa and 46% for testicular biopsy-extracted spermatozoa.Cleavage rates were also similar (68% for epididymal and 65%for testicular spermatozoa). The ongoing pregnancy rates inthis series were 50 and 43% respectively. We conclude that epididymalspermatozoa and testicular spermatozoa yield similar fertilization,cleavage and ongoing pregnancy rates using ICSI. When epididymalspermatozoa cannot be retrieved, a testicular biopsy can beperformed and the few barely motile spermatozoa thus obtainedcan be used for ICSI. It appears that all cases of obstructiveazoospermia can now be successfully treated.     

Pregnancies after intracytoplasmic sperm injection with cryopreserved testicular spermatozoa

In 25 patients (14 suffering from obstructive azoospermia, sixfrom non-obstructive azoospermia, three from astheno-azoospermiaand two from absence of ejaculation) spermatozoa were extractedfrom testicular biopsies. Intracytoplasmic sperm injection (ICSI)with fresh testicular spermatozoa was performed in 18 cases;spermatozoa in excess were cryopreserved in pills. No pregnancieswere achieved. In the remaining seven patients, testicular spermatozoawere retrieved and cryopreserved during a diagnostic testicularbiopsy. After thawing, sperm motility was assessed in 17 cases(68%), and 18 ICSI with cryopreserved testicular spermatozoawere performed. The mean two-pronuclear (2PN) fertilizationrate was 59%, the mean cleavage rate was 92%, and six clinicalpregnancies were achieved, all of them still ongoing (pregnancyrate 33%). A comparison of the results of ICSI carried out withfresh or cryopreserved testicular spermatozoa showed that themean 2PN fertilization rates per cycle (53 compared with 55%),mean cleavage rates per cycle (99 compared with 96%) and embryoquality were not significantly different In conclusion, cryopreservationof testicular spermatozoa is feasible, even in patients withnon-obstructive azoospermia, and the results of ICSI with frozen-thawedtesticular spermatozoa are similar to those obtained using freshtesticular spermatozoa. Cryopreservation of testicular spermatozoamay avoid repetition of testicular biopsies to retrieve spermatozoafor successive ICSI cycles in patients in whom the only sourceof motile spermatozoa is the testicle.     

Obstetric outcome after prenatal diagnosis in pregnancies obtained after intracytoplasmic sperm injection

In this study we compared the pregnancy outcome of 576 pregnanciesafter prenatal diagnosis with that of 540 pregnancies withoutprenatal diagnosis in our micro-injection programme. Amniocentesiswas suggested for singleton pregnancies (n = 465) and chorionicvillus sampling (CVS) was proposed for twin pregnancies (n =111 pregnancies, 222 fetuses). A total of 365 patients withsingleton pregnancies and 175 patients with twin pregnancieswho did not undergo prenatal diagnosis were selected as controls.Compared with the controls, the odds ratios in the amniocentesisgroup for preterm delivery, low birthweight, very low birthweightand fetal loss were 0.97 [95% confidence interval (CI): 0.60–1.57],1.27 (95% CI: 0.78–2.06), 1.57 (95% CI: 0.53–4.66)and 0.86 (95% CI: 0.32–2.37) respectively. Compared withthe controls, the odds ratios in the CVS group for preterm delivery,low birthweight, very low birthweight and fetal loss were 0.89(95% CI: 0.61–1.30), 1.03 (95% CI: 0.74–1.45), 0.79(95% CI: 0.41–1.53) and 0.47 (95% CI: 0.17–1.30)respectively. We concluded that, in this series of intracytoplasmicsperm injection (ICSI) pregnancies, prenatal testing did notincrease the preterm-delivery, the low-birthweight, or the verylow-birthweight rates as compared with those of the controls.In the prenatal diagnosis group, the fetal loss rate was comparableto that of the control group. Larger prospective controlledstudies are needed in order to inform patients reliably aboutthe risks and the advantages of prenatal testing in ICSI pregnancies.     

Timing of sperm and oocyte nuclear progression after intracytoplasmic sperm injection

We investigated the time course of human oocyte activation afterintracytoplasmic sperm injection (ICSI) by observing the oocytechromosome configuration at different times after injection.One day old human oocytes were injected with spermatozoa andsubjected to cytogenetic analysis at 2, 3, 4 and 5 h after injection.We found that anaphase is initiated in the vast majority ofthe oocytes between 2 and 3 h after injection, and that by 4–5h after injection most of the oocytes have reached the chromatinmass stage. Two distinguishable stages of sperm nucleus transformationwere observed. The first phase — swelling — wasreached within 2 h after the injection and was independent ofoocyte activation. The second phase — the ‘brush’-likestage or decondensed chromatin stage — was found onlyin activated oocytes. Moreover, this stage was not reached beforethe chromatin mass stage (late telophase) of the oocyte. Thesame proportion of metaphase II oocyte chromosome configurationsand unchanged sperm nuclei was found at any given time afterinjection. We conclude that: (i) ICSI allows users to obtainan almost synchronized population of activated oocytes; (ii)anaphase II is initiated in the majority of oocytes not laterthan 2–3 h after injection and telophase II is reached5 h after injection; and (iii) there are two distinguishablephases of sperm nucleus transformation after ICSI: oocyte activationindependentswelling of the sperm head and oocyte activation-dependent chromatindecondensation which is coupled to the beginning of oocyte chromosomedecondensation.     

The usefulness of a piezo-micromanipulator in intracytoplasmic sperm injection in humans

Intracytoplasmic sperm injection (ICSI) has wide clinical application. In order to achieve good results with this method, it is important to restrict the possibility of oocyte injury as much as possible, and securely inject spermatozoa into the ooplasm. For this purpose, we clinically applied piezo-ICSI, which employs a micromanipulator with piezoelectric elements, to humans, and compared the results with those obtained by conventional ICSI. Conventional ICSI and piezo-ICSI were used in 279 cycles and 335 cycles respectively. Piezo-ICSI showed significantly more favourable results, with a survival rate of 88.1% (conventional ICSI: 81.4, P < 0.001), a fertilization rate of 79.4% (conventional ICSI: 66.4%, P < 0.001), and a pregnancy rate of 23.1% (conventional ICSI: 14.9%, P < 0.05). In piezo-ICSI, the needle used is not sharpened and has a flat tip. However, deformation of the oocyte during insertion of the needle is restrained by vibration of the piezo, and the oolemma is punctured readily and securely by the piezo pulse, at the site where the spermatozoon is injected. Piezo-ICSI is a promising new technique for human ICSI that should improve the survival, fertilization and pregnancy rates after ICSI.     

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.     

Andrology: Pregnancy after intracytoplasmic sperm injection of metaphase II oocytes with spermatozoa from a man with complete retrograde ejaculation

Retrograde ejaculation is an uncommon cause of infertility,which has been treated successfully with different kinds ofartificial reproduction technique, e.g. cervical cap artificialinsemination by husband, intra-uterine and intraperitoneal insemination,standard in-vitro fertilization, pronuclear stage transfer andgamete intra-Fallopian transfer. All these techniques requirea minimal number and motility of spermatozoa obtained afterpost-masturbation voiding. In some cases, only very few spermatozoawith very poor or no motility are found in the urine voidedimmediately after masturbation. In such a case, where no morethan 14 spermatozoa were recovered over a 3 h search, intracytoplasmicsperm injection of metaphase II oocytes led to the developmentand replacement of three fair embryos, resulting in an ongoingtwin pregnancy. This technique opens up perspectives for thetreatment of men with complete retrograde ejaculation and quasi-azoospermicpost-voiding specimens.     

Andrology: The result of intracytoplasmic sperm injection is not related to any of the three basic sperm parameters

High success rates have been reported for the use of intracytoplasmicsperm injection (ICSI) in alleviating essentially andrologicalinfertility. However, neither the relationship between any ofthe sperm parameters and the result of ICSI nor the minimalsperm requirements for ICSI have been investigated so far. Inthis paper, our objective was therefore to study the relationshipbetween three basic sperm parameters (total sperm count, spermmotility and morphology) and the outcome of ICSI by retrospectiveanalyses of fertilization, embryo development and pregnancyrates in 966 micro-injection cycles, performed with ejaculatedsemen. The results showed that there was no important influencefrom either the type or the extent of sperm impairment on theoutcome of ICSI. Even in the most extreme cases of male-factorinfertility, where cryptozoospermia or total astheno- or totalteratozoospermia was diagnosed in the initial semen sample,high fertilization and pregnancy rates were obtained by ICSI.Only one condition had a strongly negative influence on theresult of ICSI: where an immotile (presumably dead) spermatozoonwas injected into the oocyte. Thus the only ultimate criterionfor successful ICSI is the presence of at least one living spermatozoonper oocyte in the pellet of the treated semen sample used formicro-injection.     

Fertilization and early embryology: Ongoing pregnancies and birth after intracytoplasmic sperm injection with frozen--thawed epididymal spermatozoa

In seven patients who did not become pregnant following microsurgicalepididymal sperm aspiration (MESA) and intracytoplasmic sperminjection (ICSI), a subsequent ICSI was performed using previouslycryopreserved supernumerary epididymal spermatozoa without re-operatingon the husband. During the original MESA procedure a mean spermconcentration of 12.3x10⁶/ml was achieved. The supernumeraryspermatozoa were cryopreserved for later use. After thawingfrozen epididymal spermatozoa a mean concentration of 1.9x10⁶spermatozoa/ml was obtained in straws containing a total volumeof sperm suspension of 250 µl. From 68 intact oocytesinjected with frozen—thawed epididymal spermatozoa, atwo pronuclear fertilization rate of 45% and a cleavage rateof 82% were obtained. A total of 17 embryos were replaced inthe seven patients, resulting in two ongoing singleton pregnanciesand one twin delivery. Six embryos were cryopreserved. In conclusion,it would appear mandatory to cryopreserve supernumerary spermatozoaduring a MESA in order to avoid subsequent further scrotal surgery.     

Successful twin pregnancy in a dual-transplant couple resulting from in-vitro fertilization and intracytoplasmic sperm injection: case report

There are numerous reports of successful pregnancy following liver transplantation. Little information is available regarding the incidence and management of infertility in transplant recipients, particularly the use of artificial reproductive technologies. We present a case of a successful twin pregnancy resulting from in-vitro fertilization with intracytoplasmic sperm injection (IVF/ICSI) in a liver transplant recipient, whose partner was a renal transplant recipient with severe oligozoospermia. With careful evaluation and monitoring, and the involvement of appropriate consultants, artificial reproductive technologies can be safely used in transplant recipient couples experiencing infertility.     

Sperm chromatin anomalies can influence decondensation after intracytoplasmic sperm injection

In this study we investigated whether morphology and chromatinanomalies in human spermatozoa can influence fertilization afterintracytoplasmic sperm injection (ICSI). We examined unfertilizedoocytes, using the fluorochrome Hoechst 33342, to determinewhether a relationship exists between failure of fertilizationand sperm chromatin quality. Sperm chromatin packaging qualitywas assessed using the chromomydn A3 (CMA3) fluorochrome, andthe presence of DNA damage in spermatozoa, using in-situ nicktranslation. Normal males present sperm parameters with a normalmorphology of >20%, CMA3 fluorescence of <30% and exhibitendogenous nicks in <10% of their spermatozoa. When patientswere separated according to these values no difference was observedin their fertilization rates after ICSL When the unfertilizedICSI oocytes were examined, we found that patients with CMA3fluorescence of <30% and nicks in <10% of their spermatozoahad only 17.5 and 21.6% respectively of their unfertilized oocytescontaining spermatozoa that remained condensed. In contrast,patients with higher CMA3 and nick values had a significantlyhigher number, 412 and 48.9%, of their unfertilized oocytescontaining condensed spermatozoa. Sperm morphology did not showany such pattern. The percentage of spermatozoa which had initiateddecondensation in unfertilized oocytes was not influenced bymorphology, CMA3 fluorescence or nicks. In light of these resultswe postulate that poor chromatin packaging and/or damaged DNAmay contribute to failure of sperm decondensation after ICSIand result in failure of fertilization.     

Human oocyte activation after intracytoplasmic sperm injection

Oocyte activation is a series of events triggered by the fertilizingspermatozoon and necessary for the beginning of the embryonicdevelopment. Calcium plays a pivotal role in this process. Herewe used confocal laser scanning microscopy to examine the changesin the concentration of intra-cellular free calcium ([Ca²⁺])in human oocytes after intracytoplasmic sperm injection (ICSI).The first considerable but short (<2 min) increase in [Ca²⁺]1was detected immediately after the penetration of the micro-injectionneedle into the ooplasm. This rise by itself did not provokeoocyte activation and was also obtained after the injectionof medium without spermatozoa. After a lag period of 4–12h, oocytes that were subsequently activated initiated a secondperiod of [Ca2⁺]1 changes. These changes were sperm-dependentand followed one of two alternative patterns, a non-oscillatoryone and an oscillatory one. The non-oscillatory pattern resembledthe changes described previously during parthenogenetic activationof mammalian oocytes. The oscillatory pattern was similar tothe changes accompanying normal fertilization in different mammalianspecies. It is concluded that the initial [Ca²⁺]1 rise provokedby the ICSI procedure is not responsible for oocyte activation,and that a release of a sperm factor(s) is required to initiatethis process.     

High implantation and pregnancy rates with testicular sperm extraction and intracytoplasmic sperm injection in obstructive and non-obstructive azoospermia

Thirty-two infertile couples with obstructive and non-obstructiveazoospermia were included in this study. Testicular sperm extraction(TESE) was performed in 16 obstructive azoospermic cases wheremicrosurgical sperm aspiration (MESA) or percutaneous spermaspiration (PESA) were impossible because of totally destroyedepididymis and 16 non-obstructive azoospermia cases with severespermatogenetic defect where the testicles were the only sourceof sperm cells. A total of 288 oocytes was obtained from 32females and 84% were injected. The fertilization rates (FR)with 2 pronuclei (PN) and cleavage rate were 50.8 and 68.2%respectively. A total of 15 pregnancies was achieved (53% perembryo transfer), nine from the obstructive and six from thenon-obstructive group. Four pregnancies resulted in clinicalabortion (26.6%). The ongoing pregnancy rate was 39.2% per embryotransfer (ET) and 343% per started cycle. A high implantationrate was also achieved (26.6% in non-obstructive and 30% inobstructive azoospermia group). Using testicular spermatozoain combination with ICSI in both obstructive and non-obstructiveazoospermic groups, high implantation and pregnancy rates canbe achieved.     

Oocyte morphology does not correlate with fertilization rate and embryo quality after intracytoplasmic sperm injection

The fertilization rates and further development of 528 humanmetaphase IT oocytes directly injected by a single spermatozoonwere analysed with respect to their morphological features atthe light microscopy level at the time of retrieval. The deviationsof oocyte morphology which were most frequently observed, afterremoval of cumulus cells, were dark incorporations, dark zonapellucida, large peri-vitelline space, spots, vacuoles, refractilebodies and irregular shape. These deviations correlated neitherwith the fertilization rate nor with the embryo quality score,as compared to ‘ideal’ oocytes. Since the majorityof oocytes displayed deviations from the ‘ideal’morphotype but were still fertilized and developed in cultureat a normal rate, they were probably as normal as ‘ideal’oocytes. Since some of these morphotypes, such as refractilebodies, have been shown to be associated with failure of fertilization,it seems that intracytoplasmic sperm injection may be an appropriatemethod of treatment for couples in whom repeated failure ofin-vitro fertilization is associated with the retrieval of dysmorphicoocytes in the presence of normal semen characteristics.     

Prospective follow-up study of 423 children born after intracytoplasmic sperm injection

In order to evaluate the safety of the intracytoplasmic sperminjection (ICSI) procedure, a prospective follow-up study of423 children born after ICSI was carried out. The aim of thisstudy was to compile data on karyotypes, congenital malformations,growth parameters and developmental milestones. Before startingthe infertility treatment, couples were asked to participatein a follow-up study including genetic counselling and prenataldiagnosis. The follow-up study of the child was based on a visitto the paediatrician-geneticist at birth or at 2 months of age,at 1 year and at 2 years of age when a physical examinationfor major and minor malformations and a psychomotoric evaluationwere done. Between April 1991 and September 1994, 320 pregnanciesobtained after ICSI led to the birth of 423 children (222 singletons,186 twins and 15 triplets). Prenatal diagnosis determined atotal of 293 karyotypes, one of which was abnormal (0.3%), andfour were benign familial structural aberrations, all inheritedfrom the paternal side. A total of 14 (3.3%) major malformationswere observed, defined as those causing functional impairmentor requiring surgical correction. Neurological or developmentalproblems at the age of 2 months were found in 14 children, fourof whom were multiples. Compared to most registers of childrenborn after assisted reproduction and to registers of malformationsin the general population, the figure of 3.3% major malformationsis within the expected range. Before drawing any firm conclusion,further careful evaluations of the available data are necessary.     

Aetiology of failed and abnormal fertilization after intracytoplasmic sperm injection1

The aim of this study was to determine why oocytes remain unfertilizedor develop three pronuclei after intracytoplasmic sperm injection(ICSI). Unfertilized and abnormally fertilized oocytes werefixed in glutaraldehyde,stained with Hoechst 33342 and examinedby fluorescence microscopy to identify oocyte, sperm and polarbody DNA.One-pronuclear oocytes were considered to be unfertilized.Atotal of 285 unfertilized oocytes were examined (104 ICSI cycles).Overall, 83% of these oocytes were not activated (still at metaphaseII) while 17% had activated and formed a single (female) pronucleus.About 66% of the unfertilized, metaphase II oocytes containeda swollen sperm head, indicating that the oocyte was correctlyinjected but had failed to activate and complete the secondmeiotic division. Premature chromosome condensation of the spermDNA was evident in 6% of these metaphase II oocytes (4% of theunfertilized oocytes). The swollen sperm head was located amongthe oocyte chromosomes in 5%of the metaphase II oocytes. Othercauses of failed fertilization in the metaphase II oocytes werethe failure of sperm head decondensation (11%) and ejectionof the spermatozoon from the oocyte (23%). A similar patternwas observed in one-pronuclear oocytes (52%, swollen sperm head;28%, intact, undecondensed sperm head; 20%, ejection of thespermatozoon), which indicates that asynchronous pronucleardevelopment does not explain the presence of one-pronuclearoocytes. A total of 41 threepronuclear oocytes were examinedand all had a single polar body, which indicates that the retentionof the second polar body leads to the formation of the thirdpronucleus.In conclusion, this study demonstrates that: (i)the major cause of fertilization failure after ICSI is failureof oocyte activation; (ii) ejection of the spermatozoon intothe perivitelline space is not a major cause of fertilizationfailure;and (iii) sperm head decondensation and oocyte activationafter ICSI can occur independently.     

The morphological normalcy of the sperm nucleus and pregnancy rate of intracytoplasmic injection with morphologically selected sperm

BACKGROUND: Our preceding studies have already demonstrated the advantage of intracytoplasmic morphologically selected sperm injection (IMSI) over the conventional IVF-ICSI procedure in terms of pregnancy rate. This study was undertaken to determine whether the increased pregnancy outcome was attributable to the preferred nuclear morphology of the selected spermatozoa, and not to the special sperm preparation technique modified by IMSI. METHODS: Comparison between two matched IMSI groups, i.e. negative comprising 38 cycles, where no spermatozoa with intact nuclei were available for microinjection; and positive, involving ovum microinjection by spermatozoa with strictly defined morphologically normal nuclei. RESULTS: Implantation and pregnancy rates were significantly higher, and abortion rates significantly lower, in the positive group compared with the negative group (25.0+/-25.9 versus 5.9+/-12.9%, F=15.8, P< or =0.01; 52.6 versus 18.4%, chi2=9.7, P< or =0.01; and 10.0 versus 57.1%, chi2=7.1, P< or =0.02, respectively). CONCLUSIONS: Implantation and pregnancy by ICSI is associated with morphological nuclear normalcy of sperm. Sperm with a morphologically abnormal nucleus usually have low fertility potential, but some with certain nuclear abnormalities may still be able to produce pregnancy following ICSI.     

Fertility with testicular sperm extraction and intracytoplasmic sperm injection in non-obstructive azoospermic men

In non-obstructive azoospermia spermatozoa can usually onlybe isolated from the testicles, and thus the most promisingtreatment model is testicular sperm extraction (TESE). Hormoneconcentrations, testicular volume determinations and testicularbiopsy results are not uniform enough to select potential candidatesfor successful TESE and intracytoplasmic sperm injection (ICSI)approaches in advance. The aim of this study was to assess theefficacy of using ICSI with testicular spermatozoa in casesof non-obstructive azoospermia and to compare the inclusioncriteria and sperm existence in the testicles in sperm obtainableand non-obtainable groups. All men showed either complete orincomplete (n = 14) maturation arrest in spermatogenesis, severehypospermatogenesis (n = 10) or Sertoli cell-only syndrome (n= 5) in their testicular biopsies. Only 14 out of a total of29 men provided enough spermatozoa for the ICSI procedure, whileno spermatozoa were found in the testicular samples of the remaining15 men. Out of 123 oocytes obtained from 14 females, 101 wereinjected with the husbands' testicular sperm cells. Total fertilizationfailure was observed in three cases. Of 39 oocytes fertilized,38 cleaved. The fertilization and cleavage rates were 38.6 and97.4% respectively. The pregnancy rate was 20.7% per initiatedcycle. In the group from whom spermatozoa were obtainable, thepregnancy rate was 42.9% per initiated cycle and 54.5% per embryotransfer. A total of six pregnancies were achieved, of whichtwo Were twins and four were singletons. One singleton pregnancyresulted in abortion in the first trimester. There was no statisticaldifference concerning the serum follicle stimulating hormoneconcentration, testicular volume and biopsy results in groupsin which spermatozoa were obtainable or not. In conclusion,although the association of TESE with ICSI obtained pregnanciesfor some patients with non-obstructive azoospermia, furtherstudies are needed to determine the inclusion criteria for successfulTESE.     

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 cryopreservedzygotes and embryos was evaluated by comparing embryo survivaland implantation between embryos derived from ICSI and thosederived from standard insemination procedures. The study includedpatients whose excess zygotes and embryos were cryopreservedbetween September 1993 and December 1994 and who subsequentlyunderwent a frozen embryo transfer. Embryo survival, clinicalpregnancy rates per transfer and pregnancy outcome were compared.Three hundred and thirty eight cryopreservation cycles, duringwhich 1471 embryos were cryopreserved, were included in thisstudy. Of those, 961 were derived from oocytes fertilized byinsemination in vitro and 510 were derived from oocytes fertilizedby ICSI. A total of 690 of the embryos (451 in the inseminationgroup and 239 in the ICSI group) have since undergone a thawcycle. The embryo survival rates were similar between the twogroups (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 (16.7and 23.8%), or the clinical miscarriage rate (16.7 and 23.8%)between the insemination and the ICSI groups respectively. Itis concluded that ICSI does not have an adverse impact on thesurvival and successful implantation of cryopreserved and thawedembryos.