Number of blastocysts biopsied as a predictive indicator to obtain at least one normal/balanced embryo following preimplantation genetic diagnosis with single nucleotide polymorphism microarray in translocation cases.

PURPOSE: The aim of this study is to investigate the minimum number of blastocysts for biopsy to increase the likelihood of obtaining at least one normal/balanced embryo in preimplantation genetic diagnosis (PGD) for translocation carriers. METHODS: This blinded retrospective study included 55 PGD cycles for Robertsonian translocation (RT) and 181 cycles for reciprocal translocation (rcp) to indicate when only one of the couples carried a translocation. Single-nucleotide polymorphism microarray after trophectoderm biopsy was performed. RESULTS: Reliable results were obtained for 355/379 (93.7 %) biopsied blastocysts in RT group and 986/1053 (93.6 %) in rcp group. Mean numbers of biopsied embryos per patient, normal/balanced embryos per patient, and mean normal/balanced embryo rate per patient were 7.4, 3.1, and 40.7 % in RT group and 8.0, 2.1, and 27.3 %, respectively, in rcp group. In a regression model, three factors significantly affected the number of genetically transferrable embryos: number of biopsied embryos (P = 0.001), basal FSH level (P = 0.040), and maternal age (P = 0.027). ROC analysis with a cutoff of 1.5 was calculated for the number of biopsied embryos required to obtain at least one normal/balanced embryo for RT carriers. For rcp carriers, the cutoff was 3.5. The clinical pregnancy rate per embryo transfer was 44.2 and 42.6 % in RT and rcp groups (P = 0.836). CONCLUSIONS: The minimum numbers of blastocysts to obtain at least one normal/balanced embryo for RT and rcp were 2 and 4 under the conditions of female age < 37 years with a basal FSH level < 11.4 IU/L.

[A follow-up study on children conceived through intracytoplasmic sperm injection].

OBJECTIVE: To investigate the perinatal complications, birth defects and growth of children conceived through intracytoplasmic sperm injection (ICSI). METHODS: A total of 575 children conceived by ICSI in our reproductive medical center, were studied. The follow-up study would include items as pregnant complications, neonatal complications, birth defects in perinatal period, subsequently detected birth defects, body weight and body length/height growth. RESULTS: Prematurity and low birth weight of ICSI children were higher in the multiple births than in the singleton births. The rates of materal gestational hypertension, neonatal asphyxia, respiratory distress syndrome, infection diseases were higher in the multiple pregnancies than in the singleton pregnancies (P < 0.05). Eleven ICSI children had died. Ten of them died in the neonatal period and they were preterm infants. One fullterm singleton ICSI child died of hepatoblastoma at the age of 2. The rate of birth defects in perinatal period was higher in ICSI children of multiple pregnancies than in the general population (P < 0.05). The body weight and body length/height of most ICSI children had obtained the standard range between 1 to 3 year-olds. CONCLUSION: The higher rates of perinatal complications in ICSI children were closely related to multiple pregnancies.

[Clinical analysis of intracytoplasmic sperm injection in patients with previous fertilization failure after conventional IVF].

OBJECTIVE: To analyze the clinical outcome of intracytoplasmic sperm injection (ICSI) in patients with previous fertilization failure after conventional IVF. METHODS: Data from 20 ICSI cases (22 ICSI cycles) with previous complete failure of fertilization or with fertilization rate < or = 20% between January 2002 and December 2004 were retrospectively analyzed. The control group consisted of 100 consecutive ICSI cycles for male factor infertility in the same period. RESULTS: The fertilization rate dramatically increased from 5.4% after conventional IVF to 76.9% after ICSI treatment (chi-squared = 264.66, P < 0.001). However, the fertilization rate in the subgroup with previous low fertilization was significantly lower than those in the control and in the subgroup without previous fertilization (67.9% vs 77.5%, 67.9% vs 84.2%). Compared with the control group, the subgroup without previous fertilization had a higher pregnancy rate and implantation rate, but only the difference in the implantation rate was statistically significant (40.5% vs 18.9%). CONCLUSION: ICSI can overcome previous fertilization failure with conventional in vitro fertilization and thus improve the clinical outcome.

[Successful preimplantation genetic diagnosis for beta-thalassemia using multiplex nested polymerase chain reaction].

OBJECTIVE: To develop single-cell multiplex nested polymerase chain reaction (PCR) assays for preimplantation genetic diagnosis (PGD) in couples at risk of having child with beta-thalassemia. METHODS: Primers were designed and synthesized according to the documented mutation sites common among Chinese. Venous blood was collected from 4 pairs of husband and wife, all heterozygotes for beta-thalassemia, and underwent multiple nested PCR. Intraooplasmic sperm injection and mechanical bio psy was used to obtain single blastomere. Multiplex nested PCR was used to detect the CD41-42 mutation and the closely linked polymorphic marker, HumTHO1 gene or CD41-42, CD41-28, IVSII654 mutation and HumTHO1 gene in the single blastomeres from four clinical PGD cycles. The normal embryos with high scores capable of continuing to divide were transplanted into the uteri. The process of gestation was observed. RESULTS: 200 lymphocytes were amplified by nested PCR. The average amplification rate of the most common 16 beta-thalassemia mutations in Chinese population was 91.3% and the average rate of allele drop out for different sites was 17.0% without differences between any 2 sites. During the 4 PGD cycles 33 embryos underwent bioassay with a success rate of 100%. 33 blastomeres were obtained to undergo PCR, of which 30 were successfully amplified with an amplification rate of 90.9%. Explicit diagnosis was obtained in 26 of the 30 embryos: 7 normal homozygotes, 11 heterozygotes, and 8 abnormal or complex heterozygotes. One or more embryos were transferred back into the uteri of the 4 women and clinical pregnancy occurred in one woman. Five weeks after the implantation B-mode ultrasonography showed monocyesis, and in the 17th week of gestational period paracentesis of cord blood showed normal homozygote. At last a normal female infant confirming the PGD result had been born, which was the first reported unaffected pregnancy resulting from PGD using multiplex nested PCR for couples as beta-thalassemia gene carriers. The results of diagnosis for embryo all corresponded to those for blastomere. The average ADO rate of blastomere was 13.3% (4/30). CONCLUSION: PGD using multiplex nested PCR, as an alternative to prenatal diagnosis, is a reliable and effective way to help couples-carriers of pathogenetic genes to get a healthy baby.

[Expression of soluble human leukocyte antigen G and its relationship to embryo development].

OBJECTIVE: To find out the expression of soluble human leukocyte antigen G (sHLA-G) and its relationship to the cleavage embryo development. METHODS: One hundred and seventy-seven day 3 cleavage embryos were detected for sHLA-G by immunohistochemistry. RESULTS: sHLA-G was detected in 57.1% cleavage embryos. The positive rate of sHLA-G in cleavage embryos developed from dipronucleate fertilized eggs was 66.2% (90/136), that developed from tripronucleate fertilized eggs was 26.8% (11/41). There was significant difference between these two groups (P < 0.01). The positive rate of sHLA-G in the grade 1 cleavage embryos developed from dipronucleate fertilized eggs was 64.3% (18/28), that in the grade 2 cleavage embryos developed from dipronucleate fertilized eggs was 91.7% (66/72), that in the grade 3 cleavage embryos developed from dipronucleate fertilized eggs was 16.7% (6/36), there were significant differences between these different embryo grades (P < 0.01), and the intensity of sHLA-G had negative relationship with the embryo grades (r = -0.503). The positive rate of sHLA-G in the first class cleavage embryos developed from tripronucleate fertilized eggs was 88.9% (32/36), that from dipronucleate fertilized eggs was 64.3% (18/28). There was significant difference in these two groups (P < 0.01). The intensity of sHLA-G in cleavage embryos developed from tripronucleate fertilized eggs was higher than that from dipronucleate fertilized eggs. The positive rate of sHLA-G in the cleavage embryos developed from dipronucleate fertilized eggs whose cell number was less than 4 was 56.7% (34/60), that from dipronucleate fertilized eggs whose cell number ranged from 5 to 6 was 67.9% (36/53), and that from dipronucleate fertilized eggs whose cell number ranged from 7 to 8 was 87.0% (20/23). There were no significant differences in these three groups. The intensity of sHLA-G had no significant difference between embryos with different cell number (P > 0.05), but it had relationship with the cell number (r = 0.267). CONCLUSION: Cleavage embryos express sHLA-G which is related with the embryo development.

[Preimplantation genetic diagnosis for beta-thalassemia using whole genome amplification].

OBJECTIVE: To achieve pregnancy with unaffected embryo using in vitro fertilization and embryo transfer (IVF-ET) and preimplantation genetic diagnosis(PGD) for the couples at risk of having children with beta-thalassemia. METHODS: A couple carrying different thalassemia mutations of codon 41/42 and codon IVS2 position 654 received standard IVF treatment and intracytoplasmic sperm injection, embryo biopsy, single cell polymerase chain reaction and DNA analyses, and only the unaffected or carrier embryos were transferred to uterus. Pregnancy confirmation, and prenatal diagnosis were done at 20 week's gestation. RESULTS: A total of 13 embryos were analyzed in the IVF cycle. PGD indicated that 2 were normal 18.1 , 3 were affected 27.3 , and 6 were carriers 54.5 ; diagnosis was not possible in 2. Three embryos were transferred to uterus on the third day after oocyte retrieval. Ultrasonography showed twin pregnancy with one blighted ovum. The prenatal diagnoses revealed that both fetuses were unaffected, one normal baby and one carrier were born. CONCLUSION: These studies represent the successful application of PGD for beta-thalassemia in China.

[Successful preimplantation genetic diagnosis for beta-thalassemia using primer extension preamplification].

OBJECTIVE: To achieve preimplantation genetic diagnosis (PGD) of the couples at risk of having children with beta-thalassemia, as an alternative to prenatal diagnosis. METHODS: Two couples carrying different thalassemia mutations of codon 41/42 and codon intervening sequence 2 position 654 received standard in vitro fertilization treatment and intracytoplasmic sperm injection, embryo biopsy and the whole genome was amplified by primer extension preamplification (PEP). Nested polymerase chain reaction was then used to amplify two mutation sites separately. Both were detected by reverse dot-blot. RESULTS: A total of 35 oocytes were retrieved from the two patients. Among them, 87% showed two pronuclei, and embryo biopsy was performed on 16 of these embryos and 25 blastomeres were obtained. The amplification efficacy was 84%. The genotype study of non-transferred and surplus embryos showed 15% of allele drop-out rate. Five embryos were transferred to the uterus of both patients. One pregnancy achieved, resulted in live healthy twin births, which confirmed the results of PGD. CONCLUSIONS: This unaffected pregnancy resulting from PGD by PEP for beta-thalassemia demonstrates that this technique can be a effective diagnostic tool for carrier couples who desire a healthy child.

[Preimplantation genetic diagnosis for beta-thalassemia].

OBJECTIVE: To investigate the effect of in vitro fertilization and embryo transfer (IVF-ET) and preimplantation genetic diagnosis (PGD) for the couples at risk of having children with beta-thalassemia. METHODS: Four couples carrying different thalassemia mutations received standard IVF treatment. Embryo biopsy was conducted. Single blastomeres were genotyped by a protocol involving primer extension preamplification, nested polymerase chain reaction and reverse dot-blot analysis. Only the unaffected embryos were transferred to the uterus. RESULTS: A total of 97 oocytes were retrieved from the four female carriers. Among them, 83% showed two pronuclei. Embryo biopsy was performed on 47 of these embryos. The amplification efficiency was 84.8%. The average ADO rate was 14.9%. Ten unaffected embryos were transferred. A twin pregnancy with one blighted ovum was confirmed at 7 weeks' gestation by ultrasonography and one normal baby and one carrier of thalassemia mutation were born finally. CONCLUSION: This unaffected pregnancy resulting from PGD for beta-thalassemia demonstrates that PGD technique can be a powerful diagnostic tool for couples carrying beta-thalassemia mutations who desire a healthy child and wish to avoid abortion of an affected fetus.