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Featured researches published by Liu.


Fertility and Sterility | 2010

CALCIUM-BINDING PROTEIN S100P IS HIGHLY EXPRESSED DURING THE IMPLANTATION WINDOW IN HUMAN ENDOMETRIUM

Xiaomei Tong; Xiaona Lin; Tao Song; Liu Liu; Songying Zhang

OBJECTIVE To investigate S100P expression and localization in human endometrium throughout the menstrual cycle. DESIGN Experimental study. SETTING University hospital. PATIENT(S) Eighty-four women. INTERVENTION(S) Complementary DNA (cDNA) microarray analysis was performed on human endometrium from days LH+4, LH+7, and hCG+7. Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis were used to detect the expression of S100P and of additional S100 family members, S100A4, S100A13, and S100A6. Immunofluorescence was used to detect the localization of S100P protein in LH+7 and LH+4 endometrium. MAIN OUTCOME MEASURE(S) Differential gene expression, levels of S100P messenger RNA (mRNA), and protein expression and immunofluorescent localization of S100P. RESULT(S) A statistical method, based on hierarchical clustering, identified genes whose expression varied at LH+7 compared with LH+4. We found that S100P was the fourth most up-regulated gene at LH+7. The S100P mRNA and protein levels were quite low during the proliferative phase and LH+4, but were elevated significantly at LH+7. The S100P expression at hCG+7 was lower than that at LH+7. However, the expression of S100A4, S100A13, and S100A6 did not vary throughout the menstrual cycle. CONCLUSION(S) S100P was specifically up-regulated during the implantation window. The underlying biological effects of S100P need further exploration.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2013

Recurrent IVF failure is associated with elevated progesterone on the day of hCG administration

Liu Liu; Feng Zhou; Xiaona Lin; Tinchiu Li; Xiaomei Tong; Haiyan Zhu; Songying Zhang

OBJECTIVE During in vitro fertilization (IVF) treatment, elevated progesterone on the day of human chorionic gonadotrophin (hCG) administration has been reported to be associated with a reduced chance of live birth. It is not known, however, if the relationship is casual or causal. In the latter situation, one would expect the incidence of elevated progesterone on the day of hCG administration to increase with the number of IVF/embryo transfer (ET) failures. The aim of this study was to investigate if the frequency of elevated progesterone on the day of hCG administration is related to the number of IVF failures. STUDY DESIGN This retrospective, observational, cohort study included a consecutive series of 6673 IVF cycles. Subjects were categorized into one of three groups: Group I, no previous IVF/ET treatment; Group II, one previous IVF/ET treatment failure; or Group III, two or more previous IVF/ET treatment failures. The main outcome measure was the proportion of cycles with elevated progesterone (>6 nmol/l) on the day of hCG administration. RESULTS After adjusting for age, oestradiol level on the day of hCG administration and number of oocytes retrieved, the proportion of women with elevated progesterone on the day of hCG administration remained significantly different between the three groups: Group I, 16.8%; Group II, 31.7%; and Group III, 39.7% (p < 0.001). CONCLUSION Elevated progesterone on the day of hCG administration is more likely in women with recurrent IVF failure. Women with two or more IVF failures are twice as likely to have elevated progesterone on the day of hCG administration as women undergoing their first IVF cycle.


Reproductive Biomedicine Online | 2015

Comparison of progesterone measurement on day of, and day after, HCG administration in IVF–embryo transfer cycles

Liu Liu; Lijuan Zhao; Tin-Chiu Li; Haiyan Zhu; Xiaona Lin; Xiaoying Jin; Xiaomei Tong; Songying Zhang

The aim of this study was to identify whether progesterone measurement on the day after HCG administration has any additional clinical value, over that obtained from progesterone measurement on the day of HCG administration. This was a single-centre, non-interventional retrospective, observational, cohort of a consecutive series of 1457 ovarian stimulation cycles leading to fresh embryo transfer cycles between January 2011 and May 2013. Progesterone was found to rise and increase rapidly by about five-fold over a 24-h period. The result of logistic regression analysis suggests that progesterone measurement around the time of HCG administration is one of the three significant (P <0.001) variables affecting clinical pregnancy rate. The predictive value of progesterone measurement on the day of HCG administration could be improved by having a further measurement 24-h later. If the progesterone levels on both days were normal, the implantation rate was 36%, but if the progesterone level on both days were high, the implantation rate dropped to 22%. Progesterone measurement should be considered on the day of HCG administration and also the day after HCG administration to provide clinically useful information on whether or not embryos should be frozen and transfer deferred to a subsequent cycle.


Fertility and Sterility | 2015

Differential expression of vascular endothelial growth factor angiogenic factors in different endometrial compartments in women who have an elevated progesterone level before oocyte retrieval, during in vitro fertilization–embryo transfer treatment

Xiaoyan Chen; Xiaoying Jin; Liu Liu; Chi Wai Man; Jin Huang; Chi Chiu Wang; Songying Zhang; Tin-Chiu Li

OBJECTIVE To investigate the relationship between endometrial expressions of angiogenic factors around the time of embryo implantation and P level before oocyte retrieval during IVF-ET treatment. DESIGN Retrospective study. SETTING University Assisted Reproductive Unit. PATIENT(S) Forty patients were recruited, 20 women with an elevated P level, and 20 women with a normal P level, into cancelled embryo transfer (ET) cycles. INTERVENTION(S) Endometrial biopsy samples were obtained from women who had an elevated or normal P level 7 days after human chorionic gonadotropin administration. The protein expression levels of VEGF-A, VEGF-C, and PLGF were examined using immunohistochemistry. MAIN OUTCOME MEASURE(S) A semiquantitative analysis was performed using histochemical-score analysis of staining intensity in the luminal epithelium, glandular epithelium, and stroma, separately. RESULT(S) Luminal epithelial expression of vascular endothelial growth factor (VEGF)-A, VEGF-C, and PLGF did not significantly differ in women with elevated or normal P levels before oocyte retrieval. Glandular epithelial expression of VEGF-A, VEGF-C, and PLGF was higher in women with elevated P levels, compared with those with normal P levels. A significantly higher stromal expression of VEGF-A and PLGF was found in women with elevated P levels. CONCLUSION(S) A high P level before oocyte retrieval was associated with expression of VEGF angiogenic factors in glandular epithelium and stromal compartment around the time of embryo implantation. Our findings suggest that the lower implantation rates observed in this group of women may relate to decreased endometrial receptivity arising from altered expression of angiogenic factors.


Reproductive Biomedicine Online | 2015

The effect of a high progesterone concentration before oocyte retrieval on the peri-implantation endometrium

Liu Liu; Sumaia Sailan; Tin-Chiu Li; Najat Mariee; S.M. Laird; Zhinong Jiang; Songying Zhang

In this single-centre, prospective cohort study, the effect of high progesterone level before oocyte retrieval on endometrial morphology and uterine natural killer cell (uKN) count in the peri-implantation period was investigated. A total of 106 women undergoing IVF treatment who did not proceed to fresh embryo transfer were included. Endometrial samples were obtained 7 days after HCG administration. Multiple regression analysis was used to identify factors affecting the results of histological staging and uNK cell count. Progesterone level on the day after HCG administration was the only significant variable associated with the results of histological staging (P = 0.004). Endometrial development in women with high progesterone level was significantly (P < 0.001) more advanced than that of women with normal progesterone; progesterone level on the day of HCG administration was the only significant variable associated with uNK cell count. The median (range) of uNK cell count of 9.6% (2.3-21.6%) in women with high progesterone was significantly (P < 0.001) higher than the median (range) of uNK cell count of 5.7% (1.4-18.7%) in women with normal progesterone. High progesterone level before oocyte retrieval was correlated with advancement in endometrial development as well as increased uNK cell count.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2014

A comparison of the miscarriage rate between women with and without polycystic ovarian syndrome undergoing IVF treatment.

Liu Liu; Xiaomei Tong; Lingying Jiang; Tin-Chiu Li; Feng Zhou; Songying Zhang

OBJECTIVE To investigate if patients with polycystic ovary syndrome (PCOS) who conceived via IVF treatment had a higher miscarriage rate than non-PCOS subjects after controlling for several important confounding variables relating to pregnancy loss. STUDY DESIGN A retrospective, observational, cohort study including a consecutive series of 564 embryo transfer cycles from PCOS patients and 7494 embryo transfer cycles from non-PCOS patients. Only the first pregnancy arising from IVF treatment was included for subsequent analysis. None of the subjects underwent ovarian diathermy or drilling prior to IVF treatment. Low dose (≤1000mg daily), short term (≤3 weeks) metformin therapy was used in 50 of the 301 PCOS subjects included in the study. RESULTS After controlling for the number of embryo transferred, the type of embryos transferred (fresh or frozen-thawed), and the stage of embryo development at the time of transfer, women with PCOS had a consistently higher biochemical pregnancy rate than women without PCOS (fresh single day 3 embryo transfer, 46.7% (7/15) vs. 14.5% (27/186), respectively, p<0.05; frozen-thawed single day 3 embryo transfer, 25.9% (7/27) vs. 6.1% (11/181), p<0.05; fresh double day 3 embryo transfer, 17.1% (12/70) vs. 7.6% (95/1256), p<0.05; frozen-thawed double day 3 embryo transfer, 7.9% (15/189) vs. 3.4% (66/1968), p<0.05). There was no significant difference in the clinical miscarriage rate between the two groups of subjects. CONCLUSION PCOS patients who conceived following IVF treatment had higher biochemical loss than women without PCOS, but the clinical miscarriage rate was no different between the two groups.


Journal of Reproductive Immunology | 2017

The effect of elevated progesterone levels before oocyte retrieval in women undergoing ovarian stimulation for IVF treatment on the genomic profile of peri-implantation endometrium

Liu Liu; Jin Huang; Tin-Chiu Li; Xu Tao Hong; S.M. Laird; Yong Dong Dai; Xiao Mei Tong; Hai Yan Zhu; Songying Zhang

To evaluate the effects of high progesterone prior to oocyte retrieval on the genomic profile of peri-implantation endometrium, we conducted this single-center, prospective cohort study. Depending on whether or not the progesterone level on the day of hCG administration and the day after hCG administration were elevated, a total of 20 women undergoing IVF treatment who did not have fresh embryo transfer were included: Group 1 refers to subjects with normal progesterone level on both days; Group 2 refers to subjects with normal progesterone level on the day of hCG administration and high progesterone level on the day after hCG administration; Group 3 refers to subjects with high progesterone level on the day of hCG administration and normal progesterone level on the day after hCG administration; Group 4 refers to subjects with high progesterone level on both days. Five subjects were included in each group. Endometrial samples were obtained 7days after hCG administration. We found that high progesterone level prior to oocyte retrieval predominantly affected components of the NK cell mediated cytotoxicity pathway in the endometrium and that significant differences were only seen when progesterone measurements on both the day of and day after hCG administration were considered together.


Human Reproduction | 2017

Pinopode score around the time of implantation is predictive of successful implantation following frozen embryo transfer in hormone replacement cycles

Xiaoying Jin; L J Zhao; D H Luo; Liu Liu; Y D Dai; X X Hu; Y Y Wang; Xiaona Lin; F Hong; Tin-Chiu Li; S. Zhang

STUDY QUESTION Is pinopode measurement of any prognostic value? SUMMARY ANSWER Pinopode expression was significantly associated with the occurrence of pregnancy after frozen embryo transfer. WHAT IS KNOWN ALREADY Pinopodes are expressed in the endometrium during the implantation period. Pinopode measurement has been proposed as a marker of endometrial receptivity. STUDY DESIGN, SIZE, DURATION A prospective cohort study was conducted at the Center of Reproductive Medicine, Sir Run Run Shaw Hospital, between 2014 and 2016, recruiting 172 women with infertility and undergoing frozen embryo transfer following IVF treatment. Among 172 participants, 46 women took part in the first study to quantify the daily changing pattern of pinopodes 3-7 days after the initiation of progesterone therapy in the hormone replacement cycles and the remaining 126 women with infertility participated in a study to examine the relationship between pinopode count and pregnancy outcome following frozen embryo transfer in hormone replacement cycles. PARTICIPANTS/MATERIALS, SETTING, METHODS The mean age of participants was 29 years old. All participants received an artificial hormone replacement protocol capable of supporting successful implantation. Endometrial biopsies from 46 women were obtained 3, 4, 5, 6 and 7 days after the initiation of progesterone therapy (P + 3, n = 6; P + 4, n = 6; P + 5, n = 11; P + 6, n = 13; P + 7, n = 10, respectively). Another 126 endometrial biopsies were obtained precisely 6 days after the initiation of progesterone. Scanning electron microscopy was used to capture the pinopode images, followed by use of the image J program to quantify the count and subtype of the pinopodes. MAIN RESULTS AND THE ROLE OF CHANCE We found that at least 60 microscopic fields were necessary to achieve a reproducible result. An intra-observer variability study showed good agreement between two measurements regarding the developing pinopode (DP) subtype (r = 0.95) and the fully developed pinopode (FDP) subtype (r = 0.86) but not for the regressing (RP) pinopode subtype (r = 0.39). The proportion of DP/total pinopodes (TP) declined rapidly form day P + 4 to a minimum on day P + 6. The percentage of FDP/TP increased rapidly from day P + 4 to reach a peak on day P + 6. On the other hand, the percentage of RP/TP reached a peak on day P + 7. Participants who conceived had a significantly (P = 0.011) higher percentage of FDP/TP on day P + 6 and significantly (P = 0.005) lower percentage of DP/TP on the same day compared with participants who did not become pregnant. Using a scoring system incorporating the percentages of DP and FDP, it was found that the pregnancy rate and the embryo implantation rate of women with a high pinopode score (82.3%; 63.0%) was significantly (P = 0.001; P = 0.046) higher than that of women with a low pinopode score (53.3%; 46.7%), respectively. There remains a possibility that the observations could have arisen due to chance. LIMITATIONS, REASONS FOR CAUTION This study examined pinopode count and subtype in the HRT cycles, and it is uncertain whether the same observations apply to in natural cycles. WIDER IMPLICATIONS OF THE FNDINGS Pinopodes have been questioned as a potential marker of endometrial receptivity for many years. Our results suggested that pinopode measurement may be of value in predicting pregnancy. STUDY FUNDING/COMPETING INTEREST(S) The study was supported by the grants from the general project of medicine and health in Zhejiang Province of China (2015KYA142; 2018KY106), the Key Research and Development Program of Zhejiang Province (2017C03022) and the National Natural Science Foundation of China (81701514).The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. We have no competing interests to declare. TRIAL REGISTRATION NUMBER ISRCTN26300668.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2014

Recurrent miscarriage and birth sex ratio

Jian Li; Liu Liu; Beiyu Liu; Sotiris Saravelos; Tin-Chiu Li

OBJECTIVE To examine the relationship between birth sex ratio and unexplained recurrent miscarriage (RM). STUDY DESIGN Retrospective, observational study including a total of 138 women with primary recurrent miscarriage (PRM) and 170 women with secondary recurrent miscarriage (SRM) in a tertiary referral recurrent miscarriage clinic between 1992 and 2010. The sex ratio of the first birth and subsequent birth were the main outcome measures. RESULTS In women with SRM: (i) The male:female sex ratio of the first stillbirth was 10:2, significantly (OR=4.76) higher than the male:female sex ratio of 1.05 among all births in UK. (ii) When the first born was a male, the male:female sex ratio of the subsequent birth was 21:35, significantly (OR=0.57) lower than the sex ratio among the general population. (iii) A male firstborn did not affect the chance of a subsequent live-birth. The findings did not apply to sex ratio in primary RM. CONCLUSION There was a subtle relationship between the sex of the first and subsequent births and secondary recurrent miscarriage, but not primary recurrent miscarriage.


Fertility and Sterility | 2017

Effects of high progesterone level on the day of human chorionic gonadotrophin administration in in vitro fertilization cycles on epigenetic modification of endometrium in the peri-implantation period

Yujing Xiong; Jianzhang Wang; Liu Liu; Xiaoyan Chen; Hui Xu; Tin-Chiu Li; Chi Chiu Wang; Songying Zhang

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Tin-Chiu Li

The Chinese University of Hong Kong

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Songying Zhang

Sir Run Run Shaw Hospital

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Xiaomei Tong

Sir Run Run Shaw Hospital

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Xiaona Lin

Sir Run Run Shaw Hospital

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Xiaoying Jin

Sir Run Run Shaw Hospital

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Feng Zhou

Sir Run Run Shaw Hospital

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Haiyan Zhu

Sir Run Run Shaw Hospital

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S. Zhang

Sir Run Run Shaw Hospital

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Chi Chiu Wang

The Chinese University of Hong Kong

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Jin Huang

The Chinese University of Hong Kong

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