NAT10-mediated N4-acetylcytidine modification is required for meiosis entry and progression in male germ cells.

Post-transcriptional RNA modifications critically regulate various biological processes. N4-acetylcytidine (ac4C) is an epi-transcriptome, which is highly conserved in all species. However, the in vivo physiological functions and regulatory mechanisms of ac4C remain poorly understood, particularly in mammals. In this study, we demonstrate that the only known ac4C writer, N-acetyltransferase 10 (NAT10), plays an essential role in male reproduction. We identified the occurrence of ac4C in the mRNAs of mouse tissues and showed that ac4C undergoes dynamic changes during spermatogenesis. Germ cell-specific ablation of Nat10 severely inhibits meiotic entry and leads to defects in homologous chromosome synapsis, meiotic recombination and repair of DNA double-strand breaks during meiosis. Transcriptomic profiling revealed dysregulation of functional genes in meiotic prophase I after Nat10 deletion. These findings highlight the crucial physiological functions of ac4C modifications in male spermatogenesis and expand our understanding of its role in the regulation of specific physiological processes in vivo.

CNOT6L couples the selective degradation of maternal transcripts to meiotic cell cycle progression in mouse oocyte.

Meiotic resumption-coupled degradation of maternal transcripts occurs during oocyte maturation in the absence of mRNA transcription. The CCR4-NOT complex has been identified as the main eukaryotic mRNA deadenylase. In vivo functional and mechanistic information regarding its multiple subunits remains insufficient. Cnot6l, one of four genes encoding CCR4-NOT catalytic subunits, is preferentially expressed in mouse oocytes. Genetic deletion of Cnot6l impaired deadenylation and degradation of a subset of maternal mRNAs during oocyte maturation. Overtranslation of these undegraded mRNAs caused microtubule-chromosome organization defects, which led to activation of spindle assembly checkpoint and meiotic cell cycle arrest at prometaphase. Consequently, Cnot6l-/- female mice were severely subfertile. The function of CNOT6L in maturing oocytes is mediated by RNA-binding protein ZFP36L2, not maternal-to-zygotic transition licensing factor BTG4, which interacts with catalytic subunits CNOT7 and CNOT8 of CCR4-NOT Thus, recruitment of different adaptors by different catalytic subunits ensures stage-specific degradation of maternal mRNAs by CCR4-NOT This study provides the first direct genetic evidence that CCR4-NOT-dependent and particularly CNOT6L-dependent decay of selective maternal mRNAs is a prerequisite for meiotic maturation of oocytes.

A novel solution for freezing individual spermatozoa using a right angular cryopiece embedded in a grooved petri dish.

Herein, we introduced a novel individual sperm freezing device named SpermCD, which consists of a right angular cryopiece (RA-Cryopiece, or "C") and a grooved petri dish ("D"). SpermCD allows embryologists to transfer sperm and perform ICSI on the same focal plane. Thirty-five patients underwent single sperm cryopreservation using SpermCD, including four patients with non-obstructive azoospermia (NOA), 14 patients with virtual azoospermia and 17 patients with cryptozoospermia. One hundred and twenty-five cryopreserved spermatozoa from nine patients were thawed on the day of the oocyte retrieval and 121 spermatozoa were found, with a sperm recovery rate of 97.1 ± 4.6%. Sixty-five MII oocytes from their spouse were injected with thawed sperm. Normal fertilization and high-quality embryo rates were 68.0% ± 33.2% and 24.4% ± 22.2%. Nineteen transplantable embryos were formed after fertilization with frozen sperm, eight of which were transplanted in five couples, resulting in four successful deliveries. SpermCD is a simple and practical individual sperm freezing device.

The CRL4-DCAF13 ubiquitin E3 ligase supports oocyte meiotic resumption by targeting PTEN degradation.

Cullin ring-finger ubiquitin ligase 4 (CRL4) has multiple functions in the maintenance of oocyte survival and meiotic cell cycle progression. DCAF13, a novel CRL4 adaptor, is essential for oocyte development. But the mechanisms by which CRL4-DCAF13 supports meiotic maturation remained unclear. In this study, we demonstrated that DCAF13 stimulates the meiotic resumption-coupled activation of protein synthesis in oocytes, partially by maintaining the activity of PI3K signaling pathway. CRL4-DCAF13 targets the polyubiquitination and degradation of PTEN, a lipid phosphatase that inhibits PI3K pathway as well as oocyte growth and maturation. Dcaf13 knockout in oocytes caused decreased CDK1 activity and impaired meiotic cell cycle progression and chromosome condensation defects. As a result, chromosomes fail to be aligned at the spindle equatorial plate, the spindle assembly checkpoint is activated, and most Dcaf13 null oocytes are arrested at the prometaphase I. The DCAF13-dependent PTEN degradation mechanism fits in as a missing link between CRL4 ubiquitin E3 ligase and PI3K pathway, both of which are crucial for translational activation during oocyte GV-MII transition.

Transforming growth factor beta1 from endometriomas promotes fibrosis in surrounding ovarian tissues via Smad2/3 signaling.

To elucidate whether the endometriotic cells of endometriomas synthesize transforming growth factor beta1 (TGF-beta1) and understand how it affects surrounding ovarian tissue. We collected biopsies of the cystic walls from 42 endometriomas and 29 mature teratomas and compared mRNA and protein expression of fibrosis-related factors between the cystic walls. Then we detected TGFB1 mRNA synthesis in endometriomas, and tested TGF-beta1 fibrotic effect in vitro. Moreover, we verified the expression of Smad2/3 signaling components in the endometriotic cystic wall in order to understand whether TGF-beta1/Smad signaling is involved in fibrosis formation of the tissue surrounding endometriomas. The cystic walls from endometriomas demonstrated severe adhesion to ovarian tissue and obvious fibrosis compared with the mature teratomas, which was proven by the increased mRNA expression of fibrotic markers. Additionally, TGFB1 was obviously expressed in the endometriotic cystic wall, and total TGFB1 protein was significantly higher in the cystic walls of endometriomas than mature teratomas. Interestingly, TGFB1 mRNA was confirmed to be specifically synthesized in the endometriotic loci through fluorescence in situ hybridization. Cultured endometriomas derived stromal cells showed obvious fibrosis after exposed to TGF-beta1. Furthermore, components of the TGF-beta1/Smad pathway such as Smad2, Smad3, Smad4, and their phosphorylated forms were also expressed in the same location as TGF-beta1, TGF-beta receptor1, and fibrotic factors expressed in the endometriotic cystic walls. In summary, endometriotic cells of endometriomas synthesize TGF-beta1 leading to fibrosis and adhesion to ovarian tissues, and TGF-beta1/Smad signaling pathway is involved in this pathological process.

S100P regulates trophoblast-like cell proliferation via P38 MAPK pathway.

S100P was originally isolated from the placenta, and is expressed in very high levels in trophoblast cells, but its role on trophoblast cells proliferation has not yet been studied. In this study, we aimed to investigate the potential role of S100P in human placental development, and the impact of its expression regulation on cellular function as well as molecular mechanisms involved in trophoblast-like cells. We found that the expression of S100P in first trimester placenta was significantly reduced in spontaneous abortion patients with respect to normal pregnant women. Up-regulation of S100P in JAR cells promoted JAR cells proliferation, and increased the expression of phosphorylated P38 (p-P38) mitogen-activated protein kinase (MAPK) and p-ERK MAPK. However, the effects of S100P on JAR cells proliferation were prevented by P38 inhibitor-SB203580, but not by ERK inhibitor-PD98059. These results showed that S100P may have a physiological role in normal pregnant development, and regulate trophoblast-like cell proliferation via modulating the P38 MAPK pathway.

Slow freezing should not be totally substituted by vitrification when applied to day 3 embryo cryopreservation: an analysis of 5613 frozen cycles.

PURPOSE: This study aimed to compare slow freezing (SF) and vitrification (VT) techniques for day 3 embryo cryopreservation in infertile couples. METHODS: This retrospective cohort study enrolled 5613 infertile patients, with 7862 frozen-thawed day 3 embryos and 3845 vitrified-warmed day 3 embryos, from 2010 to 2014, at a single center. The rates of embryo survival, pregnancy, implantation, miscarriage, live birth, and live birth weight were compared between the two groups. RESULTS: A total of 5613 cycles with 5520 transfers were analyzed. Using SF, the rates of overall embryo survival and fully intact blastomeres were lower than those in VT (91.5 vs. 97.4 % and 68.7 vs. 92.3 %, respectively). The rate of good quality embryos after thawing/warming was lower in SF than in VT. In single frozen embryo transfer cycles (FETs), the pregnancy and implantation rates were similar between the two groups (35.0 vs. 40.8 % and 34.6 vs. 35.9 %, respectively). In double FETs, the pregnancy rate per cycle was also similar between the groups (58.8 vs. 58.4 %). The implantation rate per embryo transfer was significantly higher with SF than with VT (38.8 vs. 34.6 %). With adjustment for maternal age and the number of good quality embryos, differences in implantation rate remained significant (adjusted P value, SF vs. VT P < 0.05). No independent effect was found for the method of cryopreservation on the pregnancy rate. No significant differences in the rates of miscarriage, live birth, and live birth weight were observed between the two techniques. CONCLUSIONS: Despite the significantly low embryo survival rate, fully intact blastomere rate, and good quality embryo rate in SF, the pregnancy and implantation rates were not adversely affected in single and double FETs. SF yielded an equivalent miscarriage rate, live birth rate, and live birth weight compared with VT. The SF protocol to cryopreserve day 3 embryos still should be considered.

The timing for embryo transfer after antibiotic therapy for chronic endometritis.

OBJECTIVE: To explore the optimal timing of embryo transfer after the first round treatment of chronic endometritis (CE) in vitro. MATERIALS AND METHODS: A total of 184 patients were recruited from a retrospective analysis of a large university-affiliated reproduction center in 2021. Some people chose to undergo embryo transfer in the same menstrual cycle with the first round of antibiotic treatment (Group 1, n = 29). Others received embryo transfer in the next cycle after the first round of treatment (Group 2, n = 69) or even one cycle later (Group 3，n = 96). RESULTS: Patients in Group 1 got significantly lower biochemical pregnancy rate and clinical pregnancy rate and live birth rate than Group 2 (p < 0.05) and also Group 3 (p < 0.05). Then after comparing the influence factors, we found embryo transfer in the next cycle after antibiotic treatment had a higher clinical pregnancy rate than group 1 (OR = 3.2 p < 0.05) and group 3(OR = 2.5, p < 0.05). The live birth rate in group 2 was higher than group 1(OR = 3.5, p < 0.05). CONCLUSION: These findings illustrate that embryo transfer in the next menstrual cycle is the optimal time. Embryo transfer in the same menstrual cycle with the first round of treatment reduces the pregnancy rate.

[Effects of early intervention of second-look office hysteroscopy in the prevention of adhesion reformation for moderate-severe Asherman's syndrome].

OBJECTIVE: To compare the efficacy of different time interval in the prevention of adhesion reformation after hysteroscopic adhesiolysis for moderate-severe Asherman's syndrome. METHODS: A total of 125 women with moderate-severe Asherman's syndrome undergoing hysteroscopic division of intrauterine adhesion were enrolled into this retrospective cohort study. All patients underwent second-look hysteroscopy after a certain period of the first hysteroscopic adhesiolysis, and the operation would be performed again if any adhesion existed. According to the different time interval of hysteroscopy examination, they were divided into 3 groups: A: < 1 month (n = 50), B:1-2 months (n = 39), C >2 months (n = 36). The effect of hysteroscopic adhesiolysis was evaluated by American Fertility Society (AFS) score. RESULTS: The AFS score decreased significantly after hysteroscopic adhesiolysis in each group and the normal uterine rate was up to 64.8%. The median of decreased AFS score and normal uterine rate were as follows:group A:7 point and 78%, group B:7 point and 66.7%, group C:5 point and 44.4%. And groups A and B achieved significantly (P < 0.01) greater reductions in the adhesion score than that of group C. The median time of recovery to normal uterine cavity were 1.64, 2.75 and 5.26 months in each group and great differences existed among them (P < 0.01). CONCLUSION: The time interval of second-look hysteroscopy less than 1 month offers a better prognosis in the prevention of adhesion reformation for moderate-severe Asherman's syndrome.

[Application of Femoston in hormone replacement treatment-frozen embryo transfer and its clinical outcomes].

OBJECTIVE: To explore the application of Femoston in hormone replacement treatment-frozen embryo transfer (HRT-FET) versus endometrial preparation with Progynova and examine the effects of different endometrial thickness and estradiol levels on clinical outcomes. METHODS: Retrospective analysis was conducted for a total of 1072 HRT-FET cycles at our center during January-June 2012. According to the type of medication, the patients were divided into 2 groups: Group A: Progynova only (798 cycles). Group B: non-satisfactory endometrial thickness or E2 level only by Progynova or repeated implantation failure, Progynova plus Femoston for preparing endometrium (274 cycles). Then the inter-group differences of basic profiles and clinical outcomes were compared. Comparison of clinical outcomes was performed based on different estradiol (E2) levels and endometrial thickness on the day of using progesterone. And then, the patients whose endometrial double thickness was thinner than 7 mm in Progynova + Femoston group were compared with the group of similar endometrial thickness in 2011. The data were analyzed with SPSS 16.0. RESULTS: In Group A, the percentage of first transfer, average endometrial thickness on the day of using progesterone in FET cycles were all significantly higher than Group B. And the ratio of < 7 mm was significantly higher in Group B (8.8% vs 2.4%). However, no significant differences existed in clinical pregnancy rate (54.8% vs 52.9%) or embryo implantation rate (38.1% vs 35.8%). With endometrial thickening, both clinical pregnancy and embryo implantation rates increased. There was no significant difference in maximum E2 level. Clinical pregnancy rate, embryo implantation rate and live birth rate of the patients whose endometrial double thickness was thinner than 7 mm in Group B were all higher than those of similar endometrial thickness (all Progynova only) in 2011. CONCLUSION: For patients with thin endometrium, vaginal Femoston may be added if ideal endometrial thickness or E2 level is not achieved by Progynova alone. It improves endometrial receptivity and clinical outcomes are more satisfactory.

[Impact of age, single or double, fresh or frozen embryo transfer on pregnancy outcome after in vitro fertilization treatment].

OBJECTIVE: To separately evaluate the embryo implantation rate (IR), clinical pregnancy rate and multiple pregnancy rate between women <38 years old or ≥ 38 years old in fresh or frozen thawed embryo transfer cycles, or in single or double embryo transfer cycles. METHODS: A total of 7465 single or double embryo transfer cycles between January 2010 and December 2012 at Affiliated Sir Run Run Shaw Hospital, Zhejiang University were analyzed. There were 1546 single embryo transfer cycles and 5919 double embryo transfer cycles; 2447 fresh embryo transfer cycles and 5018 frozen-thawed embryo transfer cycles. RESULTS: (1) Regardless of whether fresh or frozen-thawed embryo was used for transfer, there was no significant difference in embryo implantation rate between single and double embryo transfer groups in women <38 years. The clinical pregnancy rate significantly increased if double embryos were replaced (fresh embryo transfer, 53.3% vs 35.5%; frozen-thawed embryo transfer, 59.8% vs 38.0%, P < 0.01). Twin pregnancy rate also significantly increased (fresh embryo transfer, 28.7% vs 0.6%; frozen-thawed embryo transfer, 31.1% vs 3.0%, P < 0.01); (2) embryo implantation rate in fresh embryo transfer significantly increased in women ≥ 38 years old between groups of single or double embryo transfer (20.3% vs 9.5%, P < 0.05). No significant difference existed in IR for frozen-thawed embryo transfer. The clinical pregnancy rate significantly increased (P < 0.01) if double embryos were replaced (fresh embryo transfer, 33.2% vs 9.5%; frozen-thawed embryo transfer, 39.0% vs 21.1%, P < 0.01). Twin pregnancy rate was 19.4% in fresh embryo transfers versus 13.4% in frozen-thawed embryo transfers. There was no twin pregnancy in single embryo transfers. CONCLUSION: Compared with single embryo transfer in women < 38 years, double embryo transfer can significantly increase the rates of clinical pregnancy nd twin pregnancy. Decision is made after thorough consultations and single embryo transfer is justifiable. Double embryo transfer is indicated for women ≥ 38 years.

[Influencing factors of reproduction status of patients undergoing laparoscopic myomectomy].

OBJECTIVE: To explore the influencing factors of reproduction status in women undergoing laparoscopic myomectomy (LM). METHODS: A total of 278 LM patients were recruited.We retrospectively reviewed the reproduction status of 87 pregnant cases after LM. The correlations of their pregnancy outcomes and such clinical profiles as age, operative techniques, biological characteristics of fibroids (number, type, size and location) were analyzed.No uterine rupture occurred during the gestation period. RESULTS: None of them switched to open surgery due to laparoscopic difficulties. However, one patient had a laparoscopic suture for secondary bleeding of uterine incision. At 3 months post-operation, sonography showed no heterogeneous echo, effusion and hematoma in uterine incision.Incision through uterine cavity occurred intraoperatively in 8 cases, but no intrauterine adhesion was found on hysteroscopy 3 months later. And 87 women became pregnant and the postoperative fertilization time was from 2 months to 5 years. Age influenced the postoperative pregnancy rate.Other factors such as location, number and size of fibroid had no impact on fertility. CONCLUSION: For achieving a high conception rate and guaranteeing the safety of pregnant women, a clinician should select reasonable surgical approaches, perform accurate anatomical restoration, apply strict hemostasis and choose a right time of conception.

Are testicular sperms superior to ejaculated sperms in couples with previous ART failure due to high rate of fragmented embryos? A retrospective cohort study.

Objective: The aim was to clarify whether using testicular sperm reduces embryo fragmentation and improves cycle outcomes. Methods: Fragmented embryo was defined as an embryo in which fragments account for more than one third of the embryonic surface area. High rate of fragmented embryos was defined by a proportion of fragmented embryos higher than 50%. We recruited infertile couples who had undergone at least one ovarian stimulation cycle using ejaculated sperm but failed to conceive due to high rate of fragmented embryos in each previous cycle. After fully informed consent, the couples agreed to obtain testicular sperm by testicular puncture and use testicular sperm for intracytoplasmic sperm injection (ICSI). The normal fertilization rate, transferable embryo rate, fragmented embryo rate and cycle outcomes were compared between ejaculated sperm group (EJA-sperm group) and testicular sperm group (TESTI-sperm group). Results: Twenty-two couples who agreed to participate in our study underwent 32 ICSI cycles with ejaculated spermatozoa and 23 ICSI cycles with testicular spermatozoa. Embryo transfers were cancelled in 8 ejaculated cycles and 4 testicular cycles because of no transferable embryos. There were no significant differences in age, normal fertilization rate and high-quality embryo rate between ejaculated and testicular groups. The transferable embryo rate and implantation rate in TESTI-sperm group were significantly higher than those in EJA-sperm group (36.9% vs. 22.0%, p < 0.01; 34.2% vs. 0%, p < 0.001). The fragmented embryo rate in TESTI-sperm group was significantly lower than that in EJA-sperm group (61.2% vs. 75.7%, p < 0.05). Conclusion: Our small retrospective cohort study suggests that using testicular sperm may be a recommended option for couples with previous ART failure because of high rate of fragmented embryos. Large samples, multicenter studies or randomized controlled trial (RCT) are needed to further confirm the superiority of testicular sperm.

PABPN1 functions as a hub in the assembly of nuclear poly(A) domains that are essential for mouse oocyte development.

Growing oocytes store a large amount of maternal mRNA to support the subsequent "maternal-zygotic transition" process. At present, it is not clear how the growing oocytes store and process the newly transcribed mRNA under physiological conditions. In this study, we report non-membrane-bound compartments, nuclear poly(A) domains (NPADs), as the hub for newly transcribed mRNA, in developing mouse oocytes. The RNA binding protein PABPN1 promotes the formation of NPAD through its N-terminal disordered domain and RNA-recognized motif by means of liquid phase separation. Pabpn1-null growing oocytes cannot form NPAD normally in vivo and have defects in stability of oocyte growing-related transcripts and formation of long 3' untranslated region isoform transcripts. Ultimately, Pabpn1fl/fl;Gdf9-Cre mice are completely sterile with primary ovarian insufficiency. These results demonstrate that NPAD formed by the phase separation properties of PABPN1-mRNA are the hub of the newly transcribed mRNA and essential for the development of oocytes and female reproduction.

Preimplantation genetic testing for aneuploidy in severe male factor infertility: protocol for a multicenter randomised controlled trial.

INTRODUCTION: Conventional intracytoplasmic sperm injection (ICSI) is a widely used treatment for couples with severe male infertility. However, there are controversies regarding the selection and the damage to gametes during the ICSI procedure. Although preimplantation genetic testing for aneuploidies (PGT-A) can give genetic information about embryos for transfer and improve fertility rate, and it is widely used in women with recurrent spontaneous abortion or advanced age, PGT-A is not only more expensive but also has unclear effectiveness with respect to the improvement of fertility rate among couples with severe male infertility. High-quality, well-powered randomised clinical trials (RCTs) comparing ICSI+PGT-A and ICSI are lacking. METHODS AND ANALYSIS: This is a protocol for a multicenter, open-label RCT in four reproductive medical centers qualified for PGT technique in China. We will study couples with severe male infertility scheduled for their fertility treatment. After the blastocyst culture, eligible participants are randomised to the ICSI+PGT-A group or the conventional ICSI group in a 1:1 ratio. Other assisted reproductive procedures are similar and parallel between the two groups. The primary outcome will be live birth rate and cumulative live-birth rate . Secondary outcomes will be embryo implantation rate, biochemical pregnancy rate, clinical pregnancy rate, spontaneous abortion rate, ongoing pregnancy rate, preterm birth rate, fetal chromosomal abnormality rate, birth defect rate and treatment complications. To demonstrate or refute a difference between the two groups, we plan to include 188 participants in each group; taking consideration of 20% of dropout, the total target sample size is 450. ETHICS AND DISSEMINATION: Ethical approval was obtained from International Peace Maternity and Child Health Hospital of Shanghai Jiao Tong University Medical Science Research Ethics Committee (GKLW2016-16). Informed consent will be obtained from each participant. The findings will be disseminated to the public through conference presentations and publication in peer-reviewed scientific journals. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, NCT02941965.

[Analysis of low-quality embryo transfer strategy in in vitro fertilization and embryo transfer cycle].

OBJECTIVE: To investigate the transfer strategy of low-quality embryo in in vitro fertilization and embryo transfer (IVF-ET) cycle. METHODS: A retrospective analysis was performed for the clinical data of 621 IVF-ET cycles under controlled ovarian hyperstimulation, including 574 fresh embryo transfer (ET) cycles (Group T1) and 47 frozen-thawed embryo transfer (FET) as the first ET cycles (Group C1). Logistic regression was used to model the probability of clinical pregnancy rate based on the cycle-specific factors. RESULTS: The clinical pregnancy rate was significantly higher in Group C1 than Group T1 [38.3% (18/47) vs 22.1% (127/574), P < 0.05]. Multivariate logistic regression analysis revealed that patient age and ET method were significantly associated with the clinical pregnancy rate. After adjusting for patient age, the clinical pregnancy rate remained significantly higher in Group C1 than Group T1 (OR: 2.107, 95%CI: 1.128 - 3.939, P < 0.05). CONCLUSION: The use of FET instead of fresh ET may improve the clinical pregnancy rate in low-quality embryo cycles.

[Risk factors associated with twin pregnancy in double embryo transfer].

OBJECTIVE: To explore the risk factors associated with twin pregnancy in double embryo transfer. METHODS: A retrospective analysis was performed for 2970 double embryo transfer cycles, including 1984 cycles of fresh embryo transfer and 986 cycles of frozen-thawed embryo transfer (FET). Multiple factor Logistic regression was used. The twin pregnancy rate was studied in group of age < 35 or age ≥ 35 years old, in group of zero, single or double high-quality embryos transferred and group of fresh embryo transfer or FET cycles. RESULTS: (1) There was a significantly negative correlation between women's age and twin pregnancy according to the analysis of multiple factor Logistic regression (P < 0.01). And a significantly positive correlation existed between the number of high-quality embryos transferred, FET and twin pregnancy (P < 0.01); (2) the twin pregnancy rate of both fresh embryo transfer and FET cycles was higher in group of age < 35 years than that in group of age ≥ 35 years (16.0% vs 8.0%, P < 0.01; 26.9% vs 14.2%, P < 0.01); (3) the twin pregnancy rate of fresh embryo transfer cycles with double high-quality embryos transferred was higher than that with zero or single high-quality embryos transferred (19.1% vs 5.4%; 19.1% vs 11.0%, P < 0.01); the twin pregnancy rate of FET cycles with double high-quality embryos transferred was also higher than that with zero or single high-quality embryos transferred (32.7% vs 10.8%; 32.7% vs 20.7%, P < 0.01); (4) the twin pregnancy rate of FET cycles was significantly higher than that of fresh embryo transfer cycles (24.7% vs 14.9%, P < 0.01). CONCLUSION: Women's age, the number of high quality embryos transferred and FET are risk factors associated with twin pregnancy. At reproductive centers with a mature technique of FET, we recommend performing single high-quality embryo transfer in FET cycles to reduce the occurrence of twin pregnancy.

[Analysis of risk factors for triplet pregnancy after a simultaneous transfer of triplicate embryos].

OBJECTIVE: To analyze the risk factors for triplet pregnancy after a simultaneous transfer of triplicate embryos. METHODS: The investigators carried out a retrospective analysis of 769 cycles in which three embryos were transferred in one treatment cycle, including 298 fresh embryo transfer (ET) cycles and 471 frozen-thawed ET (FET) cycles. The impact of patient age and the number of good embryos transferred on the rates of clinical pregnancy and triplet pregnancy was studied according to different cycle types. RESULTS: (1) The rates of clinical and triplet pregnancy were significantly higher in the FET group (P < 0.05) than those in the fresh ET group; (2) all patients with a triplet pregnancy in the fresh ET group (n = 6) were younger than 35 years old (P < 0.01). There was no significant difference between the subgroups in the FET cycle according to patient age (P > 0.05); (3) when none, 1, 2 or 3 good embryos were transferred in the fresh ET cycle, the clinical pregnancy rates were 28.3%, 46.7%, 50.6% and 58.7% and the triplet pregnancy rates 0, 2.3%, 4.7% and 6.8% respectively. A similar clinical pregnancy rate (P > 0.05) and a significantly lower triplet pregnancy rate (P < 0.05) were observed when 1 good embryo was transferred versus 2 good embryos (P < 0.05). When 0, 1, 2 or 3 good embryos were transferred in the FET cycle, the clinical pregnancy rates were 38.9%, 54.8%, 59.7%, 63.9% and the triplet pregnancy rates 0, 5.0%, 13.8%, 15.8% respectively. A similar clinical pregnancy rate (P > 0.05) and a significantly lower triplet pregnancy rate (P < 0.05) were observed when 1 good embryo was transferred versus two good embryos (P < 0.05). All triplet pregnancies occurred in cycles in which more than 1 good embryo was transferred (P < 0.05). CONCLUSION: The patients have more triplet pregnancies in the FET cycle than in the fresh ET cycle. In the FET cycle, the patient age is irrelevant. It is recommended that no more than 2 embryos should be transferred. Selective single blastocyst embryo transfer is preferable if there are more than 2 good embryos available for transfer. No more than 2 embryos should be transferred in the fresh ET cycle if good embryos are available and a patient is under 35 years old.

CFTR is essential for sperm fertilizing capacity and is correlated with sperm quality in humans.

BACKGROUND: Our previous studies have demonstrated the cystic fibrosis transmembrane conductance regulator (CFTR) is important for capacitation and male fertility in mouse and guinea pig spermatozoa. However, the exact function of CFTR on human sperm fertilizing capacity, and correlation with sperm quality has not been established. The present study may shed light on some unexplained male infertility, and on a possible new method for diagnosis of male infertility and strategy for male contraception. METHODS: To assess the effect of CFTR on human sperm fertilizing capacity, we examined sperm capacitation and the acrosome reaction using chlortetracycline staining, analyzed sperm hyperactivation by computer-assisted semen analysis (CASA), measured intracellular cAMP levels using ElA and evaluated sperm penetration of zona-free hamster eggs assay in fertile men. The percentage of spermatozoa expressing CFTR from fertile, healthy and infertile men (mainly teratospermic, asthenoteratospermic, asthenospermic and oligospermic) was conducted by indirect immunofluorescence staining. RESULTS: Progesterone significantly facilitated human sperm capacitation and ZP3 triggered the acrosome reaction, both were significantly inhibited by CFTR inhibitor-172 (CFTRinh-172; 10 nM-1 microM) in a dose-dependent manner. The presence of 100 nM CFTRinh-172 markedly depressed intracellular cAMP levels, sperm hyperactivation and sperm penetration of zona-free hamster eggs. In addition, the percentage of spermatozoa expressing CFTR in the fertile men was significantly higher than healthy and infertile men categories (P < 0.01). CONCLUSIONS: CFTR is essential for human sperm fertilizing capacity and the impairment of CFTR expression in spermatozoa is correlated with a reduction of sperm quality. These results suggest that defective expression of CFTR in human sperm may lead to the reduction of sperm fertilizing capacity.

[Clinical analysis of Metzenbaum scissors in transcervical incision of a complete septate uterus].

OBJECTIVE: To evaluate the clinical efficacy of Metzenbaum scissors in the transcervical incision of a complete septate uterus. METHODS: Eight patients with a complete septate uterus were identified and recruited. The age range was 24 to 39 years old. After diagnosis by hysteroscopy, the transcervical incision was performed by Metzenbaum scissors and followed by hysteroscopic incision of corporal portion. The associated diseases were treated using laparoscopy. RESULTS: All patients were successfully treated and the operation duration was 5 - 10 minutes. The postoperative period was uneventful and there was no perforation, pelvic organ damage or water intoxication. Three months later, hysteroscopy revealed no uterine scarring or adhesion. And the shape of uterine cavity was normal. CONCLUSION: Using Metzenbaum scissors for transcervical incision of cervical portion of complete septate uterus, followed by hysteroscopic incision of corporal portion, is convenient, fast and safe. This approach has no effect upon the growth of endometrium.