Comparison of in-vitro development of embryos originating from either conventional in-vitro fertilization or intracytoplasmic sperm injection

In this retrospective study on 1628 consecutive cycles performed during a period of 4 years, development in vitro is compared of embryos obtained after either conventional in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). At 39-42 h after insemination or injection, embryos obtained after ICSI were significantly (P < 0.01) further developed (mean cell number 3.48 +/- 0.03) as compared with those obtained after IVF (3.22 +/- 0.03), whereas after 63-66 h of in-vitro development this difference was no longer present (mean cell number 6.11 +/- 0.15 versus 6.09 +/- 0.13 respectively). Culture of surplus embryos obtained after IVF resulted in a significantly higher (P < 0.001) mean incidence of blastocyst formation per cycle as compared with the ICSI group (31.8 +/- 1.9 versus 23.0 +/- 1.4 respectively). Blastocysts from both groups consisted of comparable numbers of cells. Blastocyst formation was also significantly higher when embryos were cultured in groups (31.2 +/- 1.8) compared to single culture (23.1 +/- 1.5; P < 0.01), in human tubal fluid (HTF) medium (29.2 +/- 1.7) compared with IVF-50(TM) medium (24.2 +/- 1.6; P < 0.01), and when they were cultured under 5% O(2) (30.3 +/- 1.5) compared with 20% O(2) (21.7 +/- 1.7; P < 0.01). In all culture conditions used, the mean incidence of blastocyst formation per cycle showed comparable differences in favour of the IVF group as compared with the ICSI group.     

Birth from cryopreserved embryos following in-vitro maturation of oocytes and intracytoplasmic sperm injection

This case report describes the birth of a baby following the transfer of cryopreserved embryos generated from intracytoplasmic sperm injection (ICSI) carried out on the second day after oocyte pick-up of in-vitro-matured metaphase I and germinal vesicle stage oocytes. The couple had a history of three failed intrauterine insemination attempts and reduced fertilization rates in two previous in-vitro fertilization (IVF) cycles. In the IVF-ICSI treatment cycle, 6/11 mature oocytes became fertilized following ICSI on the first day. However, the patient failed to conceive following the transfer of three embryos. Five oocytes were immature (two at metaphase I stage and three with a germinal vesicle) and these were cultured overnight. All had extruded a polar body by the following day and ICSI was therefore performed; four oocytes became fertilized, and were cryopreserved at the pronulear stage in propanediol. In the next treatment cycle, transfer of frozen embryos was planned. The pronuclear zygotes were thawed and cultured for 24 h prior to the transfer of two embryos in a cycle stimulated with low doses of follicle stimulating hormone. This resulted in a pregnancy and the delivery of a healthy baby boy. In-vitro maturation of metaphase I and germinal vesicle oocytes which are routinely collected in IVF-ICSI cycles, followed by second day ICSI fertilization, may provide a valuable source of embryos for infertile couples.      

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.     

Ca2+载体A23187对受精失败人类成熟卵母细胞的补救激活作用

目的:观察Ca²⁺载体A23187对受精失败人类成熟卵母细胞的补救激活及激活后的胚胎发育情况。方法:收集常规体外受精(IVF)及卵浆内单精子注射(ICSI)后24h仍无受精征象的成熟卵母细胞作为研究对象,5μmol/LCa²⁺载体A23187中处理5min,观察第二极体排出及原核形成情况,激活后卵母细胞在体外继续培养2d。结果:IVF组及ICSI组卵母细胞激活率分别为64.9%(24/37)和73.2%(30/41)。ICSI组受精失败卵母细胞激活后主要表现为二极体二原核(2PB+2PN)(80%,24/30),而IVF组仅有20%的被激活卵母细胞表现为2PB+2PN,两组间差异具极显著(P＜0.01)。31个2PN卵母细胞继续培养,25个发生分裂,11个发育到2-4细胞,8个发育到4-8细胞,6个发育到8-细胞以上阶段。结论:Ca²⁺载体A23187能够有效地激活ICSI后受精失败卵母细胞恢复受精并继续发育成胚胎。     

Comparison of pregnancy outcome after intracytoplasmic sperm injection and in-vitro fertilization

The aim of this study was to compare pregnancy characteristics and perinatal outcome of intracytoplasmic sperm injection (ICSI) pregnancies with pregnancies obtained after in-vitro fertilization (IVF). Retrospectively, 145 ICSI pregnancies were matched with 145 IVF pregnancies using the last menstruation data. The main outcome measures were preclinical and clinical abortions, ectopic pregnancies, multiple gestations, prenatal morbidity, prematurity, Caesarean section, birthweight, perinatal mortality and malformations for singletons, twins and triplets. Although patients were significantly younger (P < 0.001) in ICSI (31 years) than in IVF (33 years), their infertility duration (5 years) was similar. The mean number of transferred embryos (2.7 embryos per transfer) was similar in IVF and ICSI. The rates of preclinical (15%) and clinical abortions (11% in ICSI versus 15% in IVF) were not different. Four ectopic pregnancies were observed in the IVF group and none in the ICSI group. In ICSI, two minor malformations were detected and two therapeutic abortions were performed respectively for polymalformations and suspicion of cystic fibrosis. The rate of congenital malformation was 2.8% in ICSI and 2.2% in IVF. In this last group, one therapeutic abortion for malformation of neural tube was performed and two minor malformations were detected. The rate of aborted embryonic sacs before 16 weeks of gestation was not significantly lower in ICSI compared with IVF (13.7% versus 20%). The rate of multiple gestations was similar in both groups (31% in IVF and 35% in ICSI). The number of Caesarean sections was similar in IVF and in ICSI and was twice as frequent for twins versus singletons. The number of singletons born by Caesarean section was 21% after ICSI and 17% after IVF. Mean birthweights and gestational ages at birth for twins were significantly higher (P < 0.05) in ICSI than in IVF (2488 versus 2281 g and 36.5 versus 35.5 weeks). This difference was not observed for singletons. In conclusion, pregnancy characteristics and perinatal outcome after ICSI showed no increase in the number of pathologies in comparison with IVF.      

Cryopreservation of human oocytes and fertilization by two techniques: in-vitro fertilization and intracytoplasmic sperm injection

Human oocyte cryopreservation results in poor survival and subsequentfertilization rates. It has been suggested that freeze-thaw-inducedchanges in the zona pellucida may impair sperm penetration orattachment. The aim of this study was to compare fertilizationand cleavage rates in cryopreserved oocytes inseminated by conventionalin-vitro fertilization (IVF) or intracytoplasmic sperm injection(ICSI). A total of 220 oocytes, obtained from volunteers whohad undergone ovarian stimulation, were cryopreserved usinga slow freeze-rapid thaw protocol with 1.5 M propanediol asthe cryoprotectant. Surviving oocytes (n= 74, 34.4%) were randomlyallocated for fertilization by conventional IVF (group 1) orICSI (group 2) using cryopreserved spermatozoa from a singledonor of proven fertility. Fertilization was achieved in five(13.5%) of the oocytes in group 1 and 17 (45.9%) in group 2(P < 0.005), with only one oocyte in group 1 exhibiting normalfertilization as opposed to 16 (43.2%) in group 2 (P < 0.001).Similarly, one oocyte fertilized by IVF cleaved, while all fertilizedwith ICSI cleaved (P < 0.001). We conclude that althoughthe survival of oocytes is poor following cryopreservation,fertilization and cleavage rates can be enhanced significantlyusing ICSI. These data also suggest that the method of cryopreservationused in this study affected the zona pellucida, such that normalsperm attachment or penetration was impaired.     

Obstetric outcome of pregnancies after the transfer of cryopreserved and fresh embryos obtained by conventional in-vitro fertilization and intracytoplasmic sperm injection.

This study reports the obstetric outcome of pregnancies obtained after the transfer of cryopreserved or fresh embryos where the initial procedure was standard in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Pregnancies obtained after frozen IVF (n = 245) or frozen ICSI (n = 177) were compared with a control group of pregnancies after fresh embryo transfer in standard IVF (n = 245) and ICSI (n = 177) cycles were selected as controls. The controls were matched according to maternal age, parity and date of embryo transfer. In the standard IVF group, the biochemical pregnancy rates in the cryopreserved and fresh groups were 18.8 and 9.8% respectively (P < 0.01). In the ICSI group, the biochemical pregnancy rates in the cryopreserved and fresh groups were 16.4 and 6.8% respectively (P < 0.01). The miscarriage rates were comparable between the cryopreserved and fresh groups. However, in the frozen ICSI group the miscarriage rate (26.0%) was significantly higher than in the frozen conventional IVF group (13.1%) (P = 0.001). The frequencies of preterm deliveries, infants with very low birthweight and intrauterine deaths were similar in the groups. The low birthweight rates in the frozen IVF (16.1%) and ICSI (12.1%) groups were significantly lower than those in the fresh IVF (32.2%) and ICSI (32.7%) groups (P < 0.001). The major malformation rates in the frozen IVF (2.4%) and ICSI (2.9%) groups were not different from the major malformation rates in the fresh IVF (4.5%) and ICSI (2.4%) groups. In conclusion, the cryopreservation process had no negative impact on the outcome of pregnancies over 20 weeks of gestation. Long-term follow-up studies are needed in order to prove the safety of the freezing-thawing process.     

Controlled comparison of conventional in-vitro fertilization and intracytoplasmic sperm injection in patients with asthenozoospermia.

A controlled comparison between conventional in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) has been carried out for patients with 相似文献   

Maternal serum alpha-fetoprotein and human chorionic gonadotrophin in pregnancies conceived after intracytoplasmic sperm injection and conventional in-vitro fertilization.

Data in the Caucasian population suggest that maternal serum alpha-fetoprotein (AFP) and unconjugated oestriol concentrations are reduced and human chorionic gonadotrophin (HCG) concentrations are elevated in pregnancies conceived after in-vitro fertilization (IVF), leading to a higher than expected Down's syndrome screen-positive rate. There are no previous reports on the serum marker values in pregnancies conceived after intracytoplasmic injection (ICSI). Between 1996 and 1998, we measured maternal serum total HCG and AFP concentrations between 15 and 20 weeks gestation in 42 in-vitro fertilization (IVF) pregnancies and 23 ICSI pregnancies with known normal outcome. The results were compared with that of 2799 naturally occurring singleton pregnancies who were known to have a normal outcome. Median AFP multiple of the median (MOM) in ICSI pregnancies was significantly reduced to 0.76 compared with both that of the controls and that of the IVF pregnancies. For the IVF pregnancies, median HCG MOM was elevated to 1.15, and median AFP MOM was reduced to 0.88 compared with the controls, but these differences were not statistically significant. In both the IVF and ICSI pregnancies the changes might result in a falsely high Down's syndrome risk. In particular, the reduced AFP concentration in ICSI pregnancies was substantial. If this preliminary finding is substantiated by other series, the appropriate adjustment needs to be made to allow for valid interpretation of the screen result and to avoid an unnecessarily high false positive rate.     

The chromosomal constitution of multipronuclear zygotes resulting from in-vitro fertilization

We have attempted to analyse the chromosome constitution of 77 multipronuclear uncleaved zygotes obtained from our in-vitro fertilization programme. Complete karyotypes could be established for 51 tripronuclear cells and eight zygotes with four pronuclei. When compiling the results, the varying arrangement of the chromosome sets was taken into consideration. Eighteen tripronuclear zygotes showed three separate haploid metaphases (distribution pattern n/n/n), 16 cells had one haploid and one diploid chromosome set (n/2n), and in 15 zygotes the individual sets were not distinguishable (3n). Two zygotes were in fact tetraploid, the distribution of metaphases on the slide being n/3n and n/n/2n, respectively. In tripronuclear zygotes the sex chromosome ratio XXX:XXY:XYY was 14:16:18, excluding the two tetraploid cells and one zygote with a 23,X/23,X/22,-C or -Y karyotype. Chromosome abnormalities were found in 16 zygotes (31.4%) and included numerical (six cells), structural (four cells) as well as combinations of numerical and structural alterations (six cells). Four of the zygotes with four pronuclei (50%) had numerical and/or structural chromosome aberrations. Excluding two cells with one uninterpretable metaphase and a 22,-C or -Y karyotype, respectively, the sex chromosome distribution XXXX:XXXY:XXYY:XYYY was 1:1:2:1 in zygotes with four pronuclei. Another zygote was found to be pentaploid after fixation. These results suggest that analysis of multipronuclear zygotes yields valuable information about cytogenetic abnormalities occurring at the earliest stage of conception.      

Conventional in-vitro fertilization versus intracytoplasmic sperm injection in sibling oocytes from couples with tubal infertility and normozoospermic semen.

An auto-controlled study was conducted in couples with tubal infertility and normozoospermic semen. The fertilization rates and embryonic development in sibling oocytes treated, using the same semen sample, either by conventional in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) at the same time were compared. Sibling oocyte-cumulus complexes (OCC) of 56 different couples with tubal infertility and normozoospermic semen were randomly divided in order of retrieval into two groups inseminated either by conventional IVF or by ICSI. Of the retrieved OCC in the same cohort, 53.0 +/- 31.2 and 62.0 +/- 26.6% showed two distinct pronuclei after conventional IVF and ICSI respectively (not significant). Complete fertilization failure occurred after conventional IVF in 12.5% (7/56 couples). After ICSI, the comparable figure was 3.6% (2/56). The number of cases was too small to apply a statistical test to this difference. Total cleavage rates were quite similar: 86.7 +/- 28.0 and 90.1 +/- 21% of the zygotes developed into transferable embryos after IVF and ICSI respectively (not significant). Similarly, no difference in embryo quality was observed. Although injection and insemination of the oocytes were performed at the same time in the two groups, at 42 h post-insemination more embryos were at the four-cell stage after ICSI (P < 0.001) than after conventional IVF, where more embryos were still at the two-cell stage (P < 0.02). Embryo transfer was possible in all 56 couples, resulting in 16 positive serum human chorionic gonadotrophin tests (28.6% per embryo transfer), from which a clinical pregnancy resulted in 15 couples. The best embryos were selected for transfer independently of the insemination procedure, but preferably from the same origin. There appeared to be no difference in implantation potency of the embryos obtained with either technique after the non-randomized transfers.     

Preincubation of human oocytes may improve fertilization and embryo quality after intracytoplasmic sperm injection

The aim of this study was to examine the relationship between different preincubation periods of oocytes and the outcome of intracytoplasmic sperm injection (ICSI). We analysed retrospectively 95 ICSI treatment cycles performed to alleviate severe male-factor infertility. Oocyte collection was performed approximately 36 h after human chorionic gonadotrophin administration. The cumulus-corona-oocyte complexes obtained were incubated until the moment of ICSI. Fertilization, embryo development and implantation rates were analysed in four groups, which were divided according to the time lapse between oocyte retrieval and ICSI: group I, < or =3 h (18 cycles); group II, >3-< or =6 h (52 cycles); group III, >6-< or =9 h (14 cycles); and group IV, >9-< or =12 h (11 cycles). Immediately before ICSI the cumulus and corona cells were removed from the oocytes. A total of 723 metaphase II oocytes were injected: 126 from group I, 380 from group II, 126 from group III and 91 from group IV. The fertilization rates obtained were 52.3, 66.8, 65.1 and 69.2% respectively [P < 0.05 (using the chi2 test) between group I and groups II, III and IV]. Cleavage rates were similar in all groups (68.1, 69.7, 79.2 and 79.3% respectively), but the proportion of good quality embryos (< or =20% fragmentation) was significantly lower (P < 0.05) in group I (24.2%) compared with groups II (39.8%) and IV (39.6%). However, no statistically significant differences were observed between the four groups with regard to implantation rates (11.7, 13.2, 10.4 and 20.4% respectively). The results suggest that a preincubation period between oocyte retrieval and ICSI can improve the fertilization rate and embryo quality. This period might be necessary for some oocytes to reach full cytoplasmic maturity, leading to a higher activation rate upon microinjection.      

Distress level in men undergoing intracytoplasmic sperm injection versus in-vitro fertilization

The purpose of this study was to compare the psychological reactions of men undergoing intracytoplasmic sperm injection (ICSI) (n=18) or in- vitro fertilization (IVF) (n=22). Men monitored their psychological reactions daily for one complete treatment cycle from the first day of down-regulation until the outcome of treatment was known (approximately 52 days). The results showed that ICSI patients reported marginally more distress on the days prior to retrieval than the IVF patients. Other than this difference the pattern of results indicated that the psychological reactions of men undergoing ICSI or IVF were similar and that there was no need to manage these patients differently during treatment. However, ICSI patients may benefit from some reassuring comments on the days prior to retrieval when they showed more anticipatory anxiety.      

Endometrial thickness as a predictor of pregnancy after in-vitro fertilization but not after intracytoplasmic sperm injection

An ultrasonographic evaluation of the endometrium was performedin 158 patients undergoing ovarian stimulation for an in-vitroassisted reproduction programme. Endometrial thickness was evaluatedin 109 patients undergoing in-vitro fertilization (IVF) forfemale indications and in 49 patients undergoing intracytoplasmicsperm injection (ICSI) for male indications. The maximal endometrialthickness was measured on the day of human chorionic gonadotrophin(HCG) administration by longitudinal scanning of the uteruson the frozen image using electronic callipers placed at thejunction of the endometrium-myometrium interface at the levelof the fundus. Cases in which the endometrial thickness was10 mm were included in group A; cases in which the endometrialthickness was <10 mm were assigned to group B. The age ofthe patients, serum 17- oestradiol concentrations on the dayof HCG administration, the length of follicular stimulation,the number of follicles, 17- oestradiol concentrations per follicleon the day of HCG and the number of embryos transferred wereanalysed in each case. When comparing endometrial thicknessand results in IVF and ICSI patients, an endometrium <10mm predominated in IVF patients (27.5%) compared with thoseundergoing ICSI (16.7%) (P=0.05); conversely an endometrium10 mm was more frequent in ICSI than in IVF patients. The incidenceof pregnancy was higher in IVF group A patients (32/79; 41%)than in IVF group B patients (5/30; 17%) (P=0.03), whereas nosignificant difference was found between ICSI group A (13/42;31%) and ICSI group B (3/7; 43%) patients. Thus, a higher percentageof IVF patients had thin endometrium when compared with ICSIpatients; thin endometrium was a prognostic indicator of pregnancyonly in the case of a female indication for infertility (IVF).A thin endometrium in cases of female infertility may reflecta previous or present uterine pathology, whereas in indicationsof male infertility (i.e. cases using ICSI), in the absenceof any associated uterine pathology, the presence of a thinendometrium is not predictive.     

Effects of follicular fluid supplementation of in-vitro maturation medium on the fertilization and development of equine oocytes after in- vitro fertilization or intracytoplasmic sperm injection

The aim of this study was to compare the effect of the addition of follicular fluid (FF) collected from preovulatory follicles with that of oestrous mare serum (EMS) (acting as the control) to TCM-199 medium on the in-vitro maturation, fertilization and development of equine cumulus-enclosed oocytes. Oocytes (<30 mm in diameter) were obtained from the ovaries of slaughtered mares. After in-vitro maturation in the presence of the two supplements, their fertilization, cleavage and developmental potential were compared after conventional in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) using frozen-thawed spermatozoa. Follicular fluid did not increase the maturation of oocytes to metaphase II stage compared to control. After IVF, there was no difference in fertilization rates between FF- supplemented oocytes and controls (7/87, 8.4% of oocytes showing two pronuclei with FF versus 7/116, 6% with EMS; not significant). However, after ICSI, FF-supplemented oocytes showed significantly increased normal fertilization (32/85, 37.6% of two-pronuclear oocytes) and developmental potential (15/31, 48% cleavage) compared to the control oocytes (7/47, 14.9%, P < 0.01; and 2/48, 4%, P < 0.01, respectively). Overall, ICSI resulted in increased fertilization rates compared to IVF, regardless of the presence or absence of FF (39/132, 29.5% with ICSI versus 14/203, 6.9%). These results suggest that follicular fluid supplementation may improve the maturity of equine cumulus-enclosed oocytes sufficiently for the successful use of ICSI, but not sufficiently for normal sperm-egg interaction occurring during IVF.      

Fertilization and early embryology: Cytogenetic and fluorescent in-situ hybridization chromosomal studies on in-vitro fertilized and intracytoplasmic sperm injected 'failed-fertilized' human oocytes

This study was undertaken to establish baseline data on thechromosomal status of ‘failed-fertilized’ oocytesderived from in-vitro fertilization (IVF) or intracytoplasmicsperm injection (ICSI) procedures. A cytogenetic analysis wasundertaken on 162 IVF and 51 ICSI oocytes. In all, 82.1% (133/162)of the IVF and 78.4% (40/51) of the ICSI oocytes had metaphaseII (Mil) plates, of which 50.4% of the IVF and 47.5% of theICSI oocytes were analysed further. Chromosomes of the G-group(21–22) were identified with the majority of the anomalies.No overall significant difference in the aneuploidy rate wasfound for the IVF (37.3%) or ICSI (31.6%) oocytes, or with maternalage. However, chromosome anomalies, e.g. diploidy, fragmentedand broken chromatids, single sperm and oocyte chromatids, werefound in oocytes from IVF patients aged >36 years and inthe ICSI oocytes throughout the maternal age range (31–38years). The status of the polar body chromatin indicated thatthere was no overall significant difference in the maturationof the IVF and ICSI oocytes. Evidence of successful sperm deliverywas found in 72.5% (37/51) of the ICSI failed-fertilized oocytes.In this group there was a significant increase in the incidenceof premature chromosome condensation: 19.6% (10/51) containedsperm chromosomes, 7.8% (4/51) had swollen sperm heads, andthe remaining 45.0% had condensed sperm heads. The presenceof both sperm and Mil oocyte chromosomes was found in 19.6%(10/51) of the ICSI and 8.6% (14/162) of the IVF failed-fertilizedoocytes. Specific fluorescent in-situ hybridization DNA probeswere used to re-analyse the chromosomes of karyotyped ‘failed-fertilized’IVF oocytes and, for the first time, applied to the karyotypedchromosomes of failed-fertilized ICSI oocytes. The hybridizationefficiency was 86–95% for the centromere probe and 100%for probes 21 and 18.     

High fertilization and implantation rates after intracytoplasmic sperm injection

Previously reported better fertilization rate after intra-cytoplasmicsingle sperm injection (ICSI) than after subzonal inseminationof several spermatozoa was confirmed in a controlled comparisonof the two procedures in 11 patients. Intracytoplasmic sperminjection was carried out in 150 consecutive treatment cyclesof 150 infertile couples, who had failed to have fertilizedoocytes after standard in-vitro fertilization (IVF) proceduresor who were not accepted for IVF because not enough motile spermatozoawere present in the ejaculate. A single spermatozoon was injectedinto the ooplasm of 1409 metaphase II oocytes. Only 117 oocytes(8.3%) were damaged by the procedure and 830 oocytes (64.2%of the successfully injected oocytes) had two distinct pronucleithe morning after the injection procedure. The fertilizationrate was not influenced by semen characteristics. After 24 hof further in-vitro culture, 71.2% of these oocytes developedinto embryos, which were transferred or cryopreserved. Only15 patients did not have embryos replaced. Three-quarters ofthe transfers were triple-embryo transfers. High pregnancy rateswere noticed since 67 pregnancies were achieved, of which 53were clinical, i.e. a total and clinical pregnancy rate of 44.7%and 35.3% per started cycle and 49.6% and 39.2% per embryo transfer.A total of 237 supernumerary embryos were cryopreserved in 71treatment cycles.     

Chromosomal status of uni-pronuclear human zygotes following in-vitro fertilization and intracytoplasmic sperm injection

Uni-pronuclear embryos (n = 42) were analysed by fluorescencein-situ hybridization (FISH) with two to four chromosome pair-specificprobes. Half of these embryos resulted from conventional inseminationand half from intracytoplasmic sperm injection (ICSI). The majorityof uni-pronuclear embryos from conventional insemination werenormally diploid (61.9%) whereas only 9.5% of uni-pronuclearICSI embryos (P < 0.001) were diploid. In addition, a significantlyhigher number of uni-pronuclear embryos from conventional inseminationhad a Y chromosome (10/21, 47.6%) when compared with ICSI embryos(2/21, 9.5%) (P = 0.015). It is concluded that the majorityof uni-pronuclear embryos following regular in-vitro fertilizationare fertilized, whereas those from ICSI are parthenogeneticallyactivated. The latter embryos should not be considered for embryoreplacement.     

Births of normal daughters after MicroSort sperm separation and intrauterine insemination, in-vitro fertilization, or intracytoplasmic sperm injection

The world's first deliveries of normal babies after use of flow cytometric separated human sperm cells (MicroSort) for preconception gender selection are reported. Offspring were of the desired female gender in 92.9% of the pregnancies. Most of these pregnancies and births were achieved after simple intrauterine insemination.      

Comparative follow-up study of 130 children born after intracytoplasmic sperm injection and 130 children born after in-vitro fertilization

The safety of intracytoplasmic sperm injection (ICSI) as a novelprocedure of assisted fertilization may be assessed by the healthof the children born. In a prospective followup study of childrenborn after assisted procreation, 130 children born consecutivelyafter ICSI were compared with 130 control children born afterin-vitro fertilization (IVF). In both groups, mothers were matchedfor age and had the same standard treatment protocol. Therewere 74 singleton, 50 twin and six triplet children in eachgroup. Prenatal karyotyping and ultrasound screening, physicalexamination at birth and developmental milestones, with a follow-upat 2 months and 1 year, were recorded. Prenatal karyotypes wereobtained in 100 of the 130 children in the ICSI group comparedwith 22 of the 130 children in the matched IVF group. All karyotypeswere normal except for one prenatally detected mosaicism, whichwas not confirmed at birth. Four major malformations were detectedin the ICSI group (holoprosecencephaly, femur fibula ulna syndromeand palatoschisis in two children), compared with six in thematched IVF group (coarctation of the aorta, palatoschisis,hypospadias, unilateral cryptorchidism, soft tissue syndactilyand ll--hydroxylase deficiency). In the ICSI and IVF groups,mean ± SD birth weights were 2.94 ± 0.67 and 2.80± 0.73 kg, lengths were 48.46 ± 3.56) and 47.47± 5.78 cm, and head circumferences were 33.79 ±2.20 and 31.19 ± 8.88 cm respectively. Among the ICSIsingletons, the mean ± SD birth weight was 3.28 ±0.58 kg and among the twins it was 2.60 ± 0.43 kg; forthe IVF singletons and matched twins the mean ± SD birthweights were 3.19 ± 0.56 and 2.36 ± 0.61 kg respectively.In conclusion, there was no difference in the paediatric follow-upof 130 children born after ICSI and 130 children born afterconventional IVF in age-matched control patients.