To study the expression of Dickkopf-1 (DKK-1) in endometrium of pregnant mice during the peri-implantation period and the role of DKK-1 during the embryo implantation in mice. Immunohistochemical technique was employed to determine the location of DKK-1 protein in endometrium, and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) was utilized to determine the levels of DKK-1 mRNA. Our results showed that the expressions of DKK1 mRNA and protein were higher in experimental groups than in control group (P<0.01) and it increased significantly on day 3 and reached its peak on day 4, and then decreased gradually on day 5-7. The levels of DKK-1 mRNA and protein on day 4 was significantly higher than those of other groups (P<0.01). It is concluded that DKK-1 probably plays an important role in signal transudation of embryo implantation and its high expression indicates the opening of implantation window.
Embryo Implantation/*genetics ; Endometrium/*metabolism ; Intercellular Signaling Peptides and Proteins/*biosynthesis ; Intercellular Signaling Peptides and Proteins/genetics ; Protein Biosynthesis ; RNA, Messenger/genetics ; Transcription, Genetic

Objective To investigate the relative risk factors for early abortion among singleton pregnancies after assisted reproductive technology (ART) treatment. Methods A retrospective analysis was performed on 1636 singleton pregnancies, including 196 early abortion cases and 1195pregnancies with live birth after exclusion of those lost cases during follow-up, or complicated with uterine deformity, or oocyte receptor, or late abortion, or incomplete medical record, following in vitro fertilization(IVF)/ intracytoplasmic sperm injection (ICSI) treatment and the risk factors of early abortion were investigated. The early abortion rate was also compared between fresh IVF/ICSI group and frozen embryo transfer (FET) group (n=386). Results Multivariate Logistic regression analysis indicated that elder women (OR= 1. 143,95%CI: 1. 096-1. 196) and patients with polycystic ovarian syndrome (OR = 4. 309,95 % CI : 2. 564-7.243) were risk factors of spontaneous early abortion,and high mean score of transferred embryos (MSTE) (OR = 0. 808, 95% CI: 0. 717-0. 912) and endometrial triple-lined pattern on the day of human chorionic gonadotropin (hCG) administration (OR=0. 431, 95% CI: 0. 243-0.764)were protective factors. Significant difference were found in the maternal age [(32.22±4. 10) yrs vs (30.28±3. 66) yrs],the duration of infertility [(5. 90±4.26) yrs vs (5.20 ± 3. 32) yrs], basal serum follicle-stimulating hormone (FSH) level [(6. 35 ±2.30) mIU/ml vs (5.95±2.12) mIU/ml], number of transferred embryos (2. 31±0. 51) vs (2. 18±0.49), serum estradiol level on the day of hCG administration [(2467. 1 ± 1588. 8) pg/ml vs (2934. 5 ±1785.2) pg/ml] and MSTE (7.03 ±1.35 vs 7.74 ± 1.25) between the abortion group and livebirth group (all P＜0. 05). The spontaneous abortion rate was higher in the FET group than in the fresh embryo transfer group [17. 36%(67/386) vs 13.02% (213/1636), χ2 =4. 296, P=0. 023].Conclusions Women at elder age, or with long duration of infertility, high basal FSH level,polycystic ovarian syndrome, low MSTE, non-triple-lined pattern of endometrium on the day of hCG administration are at risk of spontaneous early abortion in pregnancies after ART. The rate of spontaneous abortion is higher in FET group than in fresh IVF/ICSI group.

The debate exists whether or not gonadotropin-releasing hormone (GnRH) analogs used in controlled ovarian hyperstimulation (COH) impair endometrial receptivity. Homeobox A11 (Hoxa11), Meis homeobox 1 (Meis1), cadherin 1 (Cdh1), and catenin beta 1 (Ctnnb1) are well known to be involved in successful implantation. In this study, the endometrial expression of Hoxa11, Meis1, Cdh1, and Ctnnb1 during the peri-implantation period was investigated in an in vitro fertilization (IVF) mouse model by real-time RT-PCR and Western blot to evaluate the relationship between Hoxa11, Meis1, Cdh1, and Ctnnb1 expression and the impact of the COH on endometrial receptivity. The mimic COH protocols included GnRH agonist plus human menopausal gonadotropin (HMG) (GnRH agonist group), GnRH antagonist plus HMG (GnRH antagonist group), and HMG alone (HMG group). The expression levels of Hoxa11, Meis1, Cdh1, and Ctnnb1 mRNA and protein were decreased in all of the COH groups. The expression levels of Hoxa11 and Ctnnb1 were the lowest in the GnRH agonist group, and those of Meis1 and Cdh1 were lower in the GnRH analog groups than the HMG group. There were positive correlations between the expression of Hoxa11 and Ctnnb1, as well as the expression of Meis1 and Cdh1 among all the groups. In conclusion, the COH protocols, particularly with GnRH analogs, suppressed Hoxa11, Meis1, Ctnnb1 and Cdh1 expression, in mouse endometrium during the peri-implantation period. Our data reveal a novel molecular mechanism by which the COH protocols might impair endometrial receptivity.

Embryos with a poor morphological score at cleavage stage are usually discarded because they are considered unsuitable for transfer and cryopreservation. This study examined the in vitro blastocyst development after extended culture of these embryos and the clinical outcomes after transfer of these blastocysts in warming cycles. A total of 597 blastocysts (24.7%) were obtained from 2421 embryos with low morphological scores after extended culture. One hundred and sixty blastocysts (6.6%) with optimal morphology were vitrified. Embryo utilization rate was increased from 30.8% to 32.6%. After warming, 61 out of 92 blastocysts (66.3%) survived and were transferred in 44 cycles. The clinical pregnancy rate and the implantation rate were 40.9% (18/44) and 32.8% (20/61) respectively. Thirteen healthy babies were born, and 5 pregnancies aborted spontaneously. Our study suggested that some blastocysts derived from embryos with a poor morphological score can be successfully vitrified and give rise to live births. Selection and vitrification of viable embryos after extended culture of embryos with a poor morphological score may constitute a proposal to avoid embryo wastage.

To study the expression of Dickkopf-1 (DKK-1) in endometrium of pregnant mice during the peri-implantation period and the role of DKK-1 during the embryo implantation in mice. Immunohistochemical technique was employed to determine the location of DKK-1 protein in endometrium, and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) was utilized to determine the levels of DKK-1 mRNA. Our results showed that the expressions of DKK1 mRNA and protein were higher in experimental groups than in control group (P<0.01) and it increased significantly on day 3 and reached its peak on day 4, and then decreased gradually on day 5-7. The levels of DKK-1 mRNA and protein on day 4 was significantly higher than those of other groups (P<0.01). It is concluded that DKK-1 probably plays an important role in signal transudation of embryo implantation and its high expression indicates the opening of implantation window.
Animals ; Embryo Implantation ; genetics ; Endometrium ; metabolism ; Female ; Intercellular Signaling Peptides and Proteins ; biosynthesis ; genetics ; Male ; Mice ; Pregnancy ; Protein Biosynthesis ; RNA, Messenger ; genetics ; Transcription, Genetic

To assess the relationship between pronuclear scoring and day-3 embryo quality and pregnancy outcome and to determine the clinical value of pronuclear stage scoring system in human in vitro fertilization-embryo transfer (IVF-ET) program, a pronuclear scoring system was used to score zygotes 16-20 h after insemination during conventional IVF or intracytoplasmic sperm injection (ICSI). The embryos were classified into groups Z1, Z2, Z3 and Z4. Comparisons were made of the rates of arrested embryos and excellent embryos on day 3. Comparisons of pregnancy outcome were made only in those patients in whom cohorts of similarly Z-scored embryos were transferred. The results showed that there were less arrested embryos and more excellent embryos on day 3 in groups Z1 and Z2 than those in group Z3 and Z4. More embryos arrested and less excellent embryos developed in group Z4 than group Z3. The clinical pregnancy rates resulting from the transfer of single pronuclear score homologous embryo types were similar among groups Z1, Z2 and Z3. Implantation rates of group Z1 were higher (P<0.05) than that of group Z3. These findings suggests that pronuclear scoring can predict developmental ability on day 3 and implantation potential. A evaluation that combines the Z-score and day 3 embryo morphology is useful in the determination of the most viable embryos and the number of embryos for transfer.
Cell Nucleus/*metabolism ; Embryo Implantation ; Embryo Transfer/*methods ; Fertilization in Vitro ; Infertility/therapy ; Models, Biological ; Oocytes/metabolism ; Ovary/*metabolism ; Pregnancy Outcome ; Spermatozoa/metabolism

Embryos with a poor morphological score at cleavage stage are usually discarded because they are considered unsuitable for transfer and cryopreservation. This study examined the in vitro blastocyst development after extended culture of these embryos and the clinical outcomes after transfer of these blastocysts in warming cycles. A total of 597 blastocysts (24.7%) were obtained from 2421 embryos with low morphological scores after extended culture. One hundred and sixty blastocysts (6.6%) with optimal morphology were vitrified. Embryo utilization rate was increased from 30.8% to 32.6%. After warming, 61 out of 92 blastocysts (66.3%) survived and were transferred in 44 cycles. The clinical pregnancy rate and the implantation rate were 40.9% (18/44) and 32.8% (20/61) respectively. Thirteen healthy babies were born, and 5 pregnancies aborted spontaneously. Our study suggested that some blastocysts derived from embryos with a poor morphological score can be successfully vitrified and give rise to live births. Selection and vitrification of viable embryos after extended culture of embryos with a poor morphological score may constitute a proposal to avoid embryo wastage.
Adult ; Cryopreservation ; methods ; Embryo Culture Techniques ; methods ; Embryo Transfer ; methods ; statistics & numerical data ; Female ; Fertilization in Vitro ; methods ; statistics & numerical data ; Humans ; Infertility ; pathology ; therapy ; Middle Aged ; Pregnancy ; Pregnancy Outcome ; Vitrification ; Young Adult

The debate exists whether or not gonadotropin-releasing hormone (GnRH) analogs used in controlled ovarian hyperstimulation (COH) impair endometrial receptivity.Homeobox A11 (Hoxall),Meis homeobox 1 (Meisl),cadherin 1 (Cdhl),and catenin beta 1 (Ctnnbl) are well known to be involved in successful implantation.In this study,the endometrial expression of Hoxall,Meisl,Cdhl,and Ctnnbl during the peri-implantation period was investigated in an in vitro fertilization (IVF) mouse model by real-time RT-PCR and Western blot to evaluate the relationship between Hoxall,Meisl,Cdhl,and Ctnnbl expression and the impact of the COH on endometrial receptivity.The mimic COH protocols included GnRH agonist plus human menopausal gonadotropin (HMG) (GnRH agonist group),GnRH antagonist plus HMG (GnRH antagonist group),and HMG alone (HMG group).The expression levels of Hoxall,Meisl,Cdhl,and Ctnnbl mRNA and protein were decreased in all of the COH groups.The expression levels of Hoxall and Ctnnbl were the lowest in the GnRH agonist group,and those of Meisl and Cdbl were lower in the GnRH analog groups than the HMG group.There were positive correlations between the expression of Hoxall and Ctnnbl,as well as the expression of Meisl and Cdhl among all the groups.In conclusion,the COH protocols,particularly with GnRH analogs,suppressed Hoxall,Meisl,Ctnnbl and Cdhl expression,in mouse endometrium during the peri-implantation period.Our data reveal a novel molecular mechanism by which the COH protocols might impair endometrial receptivity.

To assess the relationship between pronuclear scoring and day-3 embryo quality and pregnancy outcome and to determine the clinical value of pronuclear stage scoring system in human in vitro fertilization-embryo transfer (WF-ET) program, a pronuclear scoring system was used to score zygotes 16-20 h after insemination during conventional WF or intracytoplasmic sperm injec- tion (ICS1). The embryos were classified into groups Z1, Z2, Z3 and Z4. Comparisons were made of the rates of arrested embryos and excellent embryos on day 3. Comparisons of pregnancy outcome were made only in those patients in whom cohorts of similarly Z-scored embryos were transferred. The results showed that there were less arrested embryos and more excellent embryos on day 3 in groups Z1 and Z2 than those in group Z3 and Z4. More embryos arrested and less excellent embryos developed in group Z4 than group Z3. The clinical pregnancy rates resulting from the transfer of single pronuclear score homologous embryo types were similar among groups Z1, Z2 and Z3. Implanta- tion rates of group Z1 were higher (P<0.05) than that of group Z3. These findings suggests that pro- nuclear scoring can predict developmental ability on day 3 and implantation potential. A evaluation that combines the Z-score and day 3 embryo morphology is useful in the determination of the most viable embryos and the number of embryos for transfer.

Summary: In order to compare GnRH agonist with antagonist protocol for the same patient during controlled ovarian stimulation cycles, the in vitro fertilization and embryo transfer (IVF-ET) outcome was retrospectively studied in 81 patients undergoing 105 agonist protocols and 88 antagonist protocols. The results showed that there was no statistically significant difference in duration of ovarian stimulation, number of ampoules, oocytes retrieved, serum estradiol (E2) and progesterone (P) levels,thickness of endometrium, the zygote-and blastocyst-developmcnt rate between GnRH agonist and antagonist protocols (P>0.05). High quality embryo rate was higher in antagonist protocols, but there was no significant difference between two protocols. Implantation rate and clinical pregnant rate were significantly higher in antagonist protocol (15.82% and 30.26%, respectively) than in agonist protocol (5.26% and 10.64% respectively (P<0.05). It was concluded GnRH antagonist protocol probably improved the outcome of pregnancy of older patients with a history of multiple failure of IVF-ET in a GnRH protocol.