Hong Kong Journal of Gynaecology, Obstetrics and Midwifery
Premier Medical Centre Oocyte cryopreservation is a method to preserve fertility for young cancer... more Premier Medical Centre Oocyte cryopreservation is a method to preserve fertility for young cancer patients. Its indications have been extended to include the quarantine and storage of donor oocytes in egg donation programs, women with medical conditions that may culminate in premature ovarian insufficiency, and women who wish to safeguard fertility decline associated with ageing. In this review, we discuss the history of oocyte cryopreservation and its various clinical applications, with a focus on the safety of the procedure for cancer patients, especially those with hormone-dependent cancers such as breast cancers. We also discuss ethical considerations for women who are cryopreserving their oocytes to protect against age-related fertility loss, the optimal age to undergo oocyte cryopreservation, and the optimal number of oocytes to freeze. The risks associated with the procedure and potential risks to children born from cryopreserved oocytes are also addressed.
BACKGROUND: A combination of mifepristone and misoprostol provides an effective method of medical... more BACKGROUND: A combination of mifepristone and misoprostol provides an effective method of medical abortion for early pregnancy. This is the ®rst randomized trial comparing the use of sublingual misoprostol with vaginal misoprostol in combination with mifepristone for termination of early pregnancies up to 63 days. METHODS: A total of 224 women who requested legal termination of pregnancy up to 63 days were randomized by computergenerated list into two groups and given 200 mg of oral mifepristone followed 48 h later by either 800 mg of sublingual (n = 112) or vaginal (n = 112) misoprostol. RESULTS: Complete abortion occurred in 98.2% (95% CI: 93±99) of women in the sublingual group and 93.8% (95% CI: 88±97) in the vaginal group. There were three ongoing pregnancies in the vaginal group but none in the sublingual group. The median duration of vaginal bleeding was 17 days. There was no serious complication. Fever, chills and gastrointestinal side-effects (nausea, vomiting and diarrhoea) were signi®cantly more common in the sublingual group. CONCLUSIONS: The combination of mifepristone and misoprostol is effective for medical abortion up to 63 days. Both the sublingual and vaginal are effective routes of administration. Further randomized trials are required to ®nd out the optimal dose of sublingual misoprostol that can give the highest complete abortion rate and lowest incidence of side-effects.
Bailli Egrave Re S Best Practice and Research in Clinical Obstetrics and Gynaecology, Jun 30, 2006
The rights to reproduce and found a family are recognized as basic human rights. Infertile couple... more The rights to reproduce and found a family are recognized as basic human rights. Infertile couples should enjoy the same right to reproduce as those who have the ability to do so without assistance. Both positive and negative rights to access to assisted reproductive technologies are required in order to fully realize the reproductive rights. However, there is a limit to such a claim. The positive right of individuals to have state-funded assisted reproductive treatments has to be balanced against the provision of other societal goods and healthcare rationing. The negative right to acquire access to assisted reproductive technologies by individuals' own resources is also restrained. The barrier to such access is often of a moral nature, the standard of which depends on the values of the society.
Apoptosis and cell proliferation are widely recognized to be important physiological processes wh... more Apoptosis and cell proliferation are widely recognized to be important physiological processes which together maintain tissue homeostasis. The apoptotic and proliferative processes in 38 first trimester placentae were quantified using terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling (TUNEL) and an antibody against Ki-67 antigen, respectively. In 14 cases, the estimation of apoptotic index was repeated with sections stained with haematoxylin and eosin by identifying the morphological features of apoptosis. We found that the indices obtained by either method correlated well with each other although a lower rate was obtained with the haematoxylin and eosin stained sections. Apoptosis was found in clusters mainly in syncytiotrophoblasts in association with fibrinoid deposits while proliferating activity was limited to cytotrophoblasts and stromal cells. A significant inverse correlation was observed between the proliferative index and gestational age as well as the apoptotic index. While the extent of apoptosis decreased with advanced gestational age, the correlation was not statistically significant. These findings provide a potential explanation for villous remodelling during trophoblastic invasion in early pregnancy.
Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine, 2007
We compared the ultrasonographic parameters for endometrial receptivity between 2 consecutive in ... more We compared the ultrasonographic parameters for endometrial receptivity between 2 consecutive in vitro fertilization (IVF) cycles in the same patients. Patients who had undergone 2 in vitro fertilization cycles between November 2002 and December 2004 were recruited. A 3-dimensional ultrasonographic examination with power Doppler imaging was performed on the day of oocyte retrieval to determine the endometrial thickness, endometrial pattern, pulsatility and resistive indices of uterine vessels, endometrial volume, vascularization index, flow index, and vascularization flow index of endometrial and subendometrial regions. Of 662 patients, 95 (14.4%) underwent 2 consecutive cycles using the same stimulation regimen during the study period. There were no significant differences in these ultrasonographic parameters between the first and second cycles. The intraclass correlation coefficient (ICC) for endometrial volume was significantly higher than that of other ultrasonographic parameter...
Uterine arteriovenous malformation is a rare condition. Uterine artery embolization offers the po... more Uterine arteriovenous malformation is a rare condition. Uterine artery embolization offers the possibility of conservative management as opposed to the traditional hysterectomy. We report a case with recurrent uterine arteriovenous malformation confirmed by angiography and successfully treated with a second embolization procedure. A 33-year-old woman presented with heavy vaginal bleeding. The diagnosis of uterine arteriovenous malformation was suspected on Doppler ultrasonography and confirmed by angiography. The first embolization procedure was performed using polyvinyl alcohol and steel coils. Recurrence was diagnosed 1 year later with the same imaging techniques. The second embolization procedure was performed using histoacryl. The patient remained asymptomatic at 1-year of follow-up. Minimally invasive management is an option in recurrent uterine arteriovenous malformation.
Apoptosis and cell proliferation are widely recognized to be important physiological processes wh... more Apoptosis and cell proliferation are widely recognized to be important physiological processes which together maintain tissue homeostasis. The apoptotic and proliferative processes in 38 first trimester placentae were quantified using terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling (TUNEL) and an antibody against Ki-67 antigen, respectively. In 14 cases, the estimation of apoptotic index was repeated with sections stained with haematoxylin and eosin by identifying the morphological features of apoptosis. We found that the indices obtained by either method correlated well with each other although a lower rate was obtained with the haematoxylin and eosin stained sections. Apoptosis was found in clusters mainly in syncytiotrophoblasts in association with fibrinoid deposits while proliferating activity was limited to cytotrophoblasts and stromal cells. A significant inverse correlation was observed between the proliferative index and gestational age as well as the...
Oral communication abstracts and relate the results to studies on ultrasound diagnosis in view of... more Oral communication abstracts and relate the results to studies on ultrasound diagnosis in view of necessity of surgical intervention. Material and Methods: Two-hundred and thirty-four ovaries of postmenopausal women, who had died from non-gynaecological diseases, were examined prospectively and consecutively, by the pathologist (G.P. Blom), for cystic structures. The results were compared to recent ultrasound studies of adnexal cysts. Results: Ovarian cysts were found in 15.4% of the women. Paraovarian cysts were found in 4.7% of the women. All cysts were benign, except for one woman, who had bilateral serous cystadenoma of borderline type. Macroscopically the borderline cysts were multilocular with mean diameters of 60 mm and 15 mm, respectively. Conclusions: The results were in agreement with diagnostic ultrasound studies. The fact that we found benign ovarian and paraovarian cysts in 21.1% of the women should in our opinion make the gynecologists reconsider the need for surgical intervention in favor of follow-up.
Objectives: To evaluate the clinical significance and characteristics of intrauterine hematomas d... more Objectives: To evaluate the clinical significance and characteristics of intrauterine hematomas detected in the first trimester of pregnancy. Methods: A prospective study was designed to compare the obstetrical outcome in 43 pregnant women with intrauterine hematoma, who spontaneously aborted to 187 controls, who delivered after the hematoma was diagnosed. Statistical analysis was assessed by ÷2 analysis and two-tailed Fisher's exact test. Means of continuous variables were compared by two-tailed Student's t-test. Results: Smoking and multiparity were significantly greater in the abortion group. There was no significant difference with regard to maternal age, and medical history such as chronic hypertension (P = 0.66), gestational diabetes (P = 0.31), termination of pregnancy (P = 0.86), previous loss (P = 0.39) and perinatal death (P = 0.35). Retroplacental (P = 0.72) or subchorionic (P = 0.72) position of the hematoma was not significantly correlated with an increased risk for spontaneous abortion. The cervical (P = 0.004) and posterior (P = 0.002) location of the hematoma has significantly influenced the risk of abortion. The abortion rate was significantly greater in those who were spotting (P = 0.02), bleeding (P = 0.03) or crumping (P = 0.001), but not in those who were discharging (P = 0.1). Among patients having no symptoms the rate of abortion was significantly lower (P = 0.02). The volume ratio of the haematoma and the gestational sac was significantly greater in the abortion group (p < 0.001). Conclusion: Our study suggests that the presence and the characteristic of an intrauterine hematoma during the first trimester may identify a population of patients at increased risk for adverse pregnancy outcome.
There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndro... more There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndrome (PCOS). In addition to different diagnostic criteria used, the ethnic background of women with PCOS may affect the clinical, hormonal, and metabolic characteristics of this condition. We present here studies related to the clinical, hormonal, and metabolic characteristics and response to the treatment of PCOS in Asia, which may be different from those in Western countries. It is important to take into consideration the ethnic background of patients in future studies related to PCOS.
Journal of the Society for Gynecologic Investigation, 2006
To study the effects of green tea on body weight, and biochemical and hormonal profiles in obese ... more To study the effects of green tea on body weight, and biochemical and hormonal profiles in obese Chinese women with polycystic ovary syndrome (PCOS). Thirty-four obese Chinese women with PCOS were randomized into either treatment with green tea capsules or placebo for 3 months. The anthropometric measurements, and biochemical and hormonal profiles before and after treatment in each group were compared. The body weight of the green tea group decreased by a nonsignificant 2.4% after treatment; whereas the body weight, body mass index (BMI), and body fat content of the control group were significantly higher after 3 months. There were no differences in any of the hormone levels measured in either group. The biochemical profiles of the two groups were also similar except that there was a small but significant rise in the triglyceride level in the green tea group. Fewer patients in the green tea group remained amenorrhoeic, but this was not significantly different from the control group. Green tea supplementation did not significantly reduce body weight in obese women with PCOS, nor did it alter the glucose or lipid metabolism.
Journal of the Society for Gynecologic Investigation, 2005
To investigate changes in the uterine artery and ovarian stromal blood flow in relation to the ti... more To investigate changes in the uterine artery and ovarian stromal blood flow in relation to the time of the day after pituitary down-regulation during in vitro fertilization treatment. Thirteen women were recruited. The uterine artery blood flow was studied using pulsed color Doppler ultrasonography and the ovarian stromal blood flow was measured using three-dimensional power Doppler ultrasonography. Ultrasound scan examinations and blood pressure measurements were performed in the morning and evening. The diastolic and the mean arterial pressures were significantly higher in the evening. An increase in the uterine artery pulsatility index and resistance index in the evening was observed. The ovarian vascularization index, vascularization flow index, and right ovarian flow index were significantly lower in the evening. Despite the small sample size, we have demonstrated the presence of a diurnal change in uterine artery and ovarian stromal blood flow after pituitary down-regulation. Such changes may be related to the systemic change in the sympathetic system and hence vascular resistance. Future study regarding ovarian stromal blood flow should take into account the effect of the time of the day on the readings in order to avoid misleading interpretation of data.
Journal of the Society for Gynecologic Investigation, 2005
To investigate any change in the ovaries, including early follicular serum follicle-stimulating h... more To investigate any change in the ovaries, including early follicular serum follicle-stimulating hormone (FSH) level, total ovarian volume, total antral follicle count, and ovarian stromal blood flow, in patients who had undergone abdominal hysterectomy for benign conditions. Fifteen women with abdominal hysterectomy and conservation of ovaries for benign conditions and who were between 29 and 44 years old were recruited to undergo three-dimensional ultrasound examination with power Doppler to assess total ovarian volume, total antral follicle count, and vascularization index (VI), flow index (FI), and vascularization flow index (VFI) of ovarian stromal blood flow. Serum FSH, estradiol, and progesterone levels were checked on the same day. The results of the assessments were considered taken during the early follicular phase if the estradiol and progesterone levels were basal. Fifteen age-matched healthy women underwent the same assessments on the second day of menstruation. Women with hysterectomy had significantly elevated serum FSH level and lower ovarian stromal blood flow indices, including VI, FI, and VFI, as compared with healthy women. The total antral follicle count and the total ovarian volume were similar between the two groups. These changes may suggest altered ovarian function after hysterectomy.
Kong. His main research interests are assisted reproduction technology, assessment of ovarian res... more Kong. His main research interests are assisted reproduction technology, assessment of ovarian reserve and three-dimensional ultrasound in reproductive medicine. He has published about 100 papers in refereed journals.
Kong. His main research interests are assisted reproduction technology, assessment of ovarian res... more Kong. His main research interests are assisted reproduction technology, assessment of ovarian reserve and three-dimensional ultrasound in reproductive medicine. He has published about 100 papers in refereed journals.
This randomized trial compared the sequential use of letrozole and gonadotrophin (HMG) with HMG o... more This randomized trial compared the sequential use of letrozole and gonadotrophin (HMG) with HMG only in poor ovarian responders undergoing IVF. Patients with < four oocytes retrieved in previous IVF cycles or < 5 antral follicles were randomized to either letrozole for 5 days followed by HMG or HMG alone. 53 women were recruited. The letrozole group had significantly lower dosage of HMG (P < 0.001), shorter duration of HMG (P < 0.001) and fewer oocytes (P = 0.001) when compared to the control group. Live-birth rate was comparable with a significantly lower miscarriage rate in the letrozole group ((P = 0.038). Serum FSH concentrations were comparable in both groups except on Day 8, while estradiol concentrations were all significantly lower in the letrozole group from day 4. Follicular fluid concentrations of testosterone, androstenedione, FSH and AMH were significantly higher in the letrozole group (P = 0.009, P = 0.001, P = 0.046 and P =0.034 respectively). When compared to HMG alone, sequential use of letrozole and HMG in poor responders resulted in significantly lower total dosage and shorter duration of HMG, a comparable live-birth rate, a significantly lower miscarriage rate but a more favourable hormonal environment of follicular fluid.
To investigate Hong Kong couples&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;... more To investigate Hong Kong couples&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; attitudes and concerns about using preimplantation genetic diagnosis (PGD) and human leukocyte antigens (HLA) typing to conceive a disease-free and tissue-compatible &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;Saviour Child (SC)&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; to save an afflicted sibling. Two cohorts of Chinese couples, one with natural pregnancies and the other receiving in vitro fertilization (IVF) services, were studied using a structured questionnaire. Although most couples believed that embryos possess moral rights, they considered it acceptable to reproduce a donor child if it was safe for the child, and tissue transplantation was the only available treatment for the sick sibling. Most couples believed that the donor child would not suffer adverse physical or psychological effects but rather would gain positive psychological benefits, and opined that parents using PGD/HLA-typing suffer sacrificially for their children. In response to one specific question, one-third of the couples agreed to use the donor child as a lifetime organ donor and supported the use of PGD for non-medical gender selection. One-quarter were willing to reject PGD/HLA-typing because of its potential for non-medical genetic enhancement. Probably influenced by the Chinese tradition of strong familism, couples in Hong Kong generally show positive attitudes towards using PGD/HLA-typing to reproduce a &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;SC&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; to save a sibling affected with life-threatening diseases amenable to treatment with genetically compatible tissue.
To compare the efficacy of a nitric oxide donor (isosorbide mononitrate) and a prostaglandin E 1 ... more To compare the efficacy of a nitric oxide donor (isosorbide mononitrate) and a prostaglandin E 1 analogue (misoprostol) for cervical priming before suction termination of pregnancy. METHODS: This was a randomized, double blind, placebocontrolled trial. One hundred twenty-six healthy women requesting termination of pregnancy between 9 and 12 weeks' gestation were recruited. Women were randomized into three groups: control, isosorbide mononitrate, and misoprostol. All women were given moistened intravaginal study drugs (placebo, 40 mg of isosorbide mononitrate, or 400 g of misoprostol) 4-6 hours before suction evacuation. Side effects were assessed 3 hours after drug administration. The cervical dilatation and the cumulative force required to dilate the cervix to 8 mm were measured by a cervical tonometer before suction evacuation. Operative blood loss was measured after sieving off the products of gestation.
Previous studies analysing the incidences of mitochondrial DNA (mtDNA) deletions and mtDNA conten... more Previous studies analysing the incidences of mitochondrial DNA (mtDNA) deletions and mtDNA content in unfertilized oocytes in relation to donors' age have been controversial. The objective of the study was to compare these two parameters in unfertilized oocytes and relate them to the donors' age. Fifty-two women donated 155 unfertilized metaphase II (MII) oocytes. The incidence of 4977 bp deletion was 34.6%, and the mtDNA copy number was 598 350 ؎ 265 862. Women Ն35 years of age had a significantly higher incidence of 4977 bp deletion, lower mtDNA copy number, higher FSH level and poorer ovarian response when compared with younger women. The mtDNA copy number was negatively correlated with the donor's age. The higher incidence of mtDNA deletion and lower mtDNA copy number in older women suggested that these two parameters may reflect ovarian ageing.
Hong Kong Journal of Gynaecology, Obstetrics and Midwifery
Premier Medical Centre Oocyte cryopreservation is a method to preserve fertility for young cancer... more Premier Medical Centre Oocyte cryopreservation is a method to preserve fertility for young cancer patients. Its indications have been extended to include the quarantine and storage of donor oocytes in egg donation programs, women with medical conditions that may culminate in premature ovarian insufficiency, and women who wish to safeguard fertility decline associated with ageing. In this review, we discuss the history of oocyte cryopreservation and its various clinical applications, with a focus on the safety of the procedure for cancer patients, especially those with hormone-dependent cancers such as breast cancers. We also discuss ethical considerations for women who are cryopreserving their oocytes to protect against age-related fertility loss, the optimal age to undergo oocyte cryopreservation, and the optimal number of oocytes to freeze. The risks associated with the procedure and potential risks to children born from cryopreserved oocytes are also addressed.
BACKGROUND: A combination of mifepristone and misoprostol provides an effective method of medical... more BACKGROUND: A combination of mifepristone and misoprostol provides an effective method of medical abortion for early pregnancy. This is the ®rst randomized trial comparing the use of sublingual misoprostol with vaginal misoprostol in combination with mifepristone for termination of early pregnancies up to 63 days. METHODS: A total of 224 women who requested legal termination of pregnancy up to 63 days were randomized by computergenerated list into two groups and given 200 mg of oral mifepristone followed 48 h later by either 800 mg of sublingual (n = 112) or vaginal (n = 112) misoprostol. RESULTS: Complete abortion occurred in 98.2% (95% CI: 93±99) of women in the sublingual group and 93.8% (95% CI: 88±97) in the vaginal group. There were three ongoing pregnancies in the vaginal group but none in the sublingual group. The median duration of vaginal bleeding was 17 days. There was no serious complication. Fever, chills and gastrointestinal side-effects (nausea, vomiting and diarrhoea) were signi®cantly more common in the sublingual group. CONCLUSIONS: The combination of mifepristone and misoprostol is effective for medical abortion up to 63 days. Both the sublingual and vaginal are effective routes of administration. Further randomized trials are required to ®nd out the optimal dose of sublingual misoprostol that can give the highest complete abortion rate and lowest incidence of side-effects.
Bailli Egrave Re S Best Practice and Research in Clinical Obstetrics and Gynaecology, Jun 30, 2006
The rights to reproduce and found a family are recognized as basic human rights. Infertile couple... more The rights to reproduce and found a family are recognized as basic human rights. Infertile couples should enjoy the same right to reproduce as those who have the ability to do so without assistance. Both positive and negative rights to access to assisted reproductive technologies are required in order to fully realize the reproductive rights. However, there is a limit to such a claim. The positive right of individuals to have state-funded assisted reproductive treatments has to be balanced against the provision of other societal goods and healthcare rationing. The negative right to acquire access to assisted reproductive technologies by individuals' own resources is also restrained. The barrier to such access is often of a moral nature, the standard of which depends on the values of the society.
Apoptosis and cell proliferation are widely recognized to be important physiological processes wh... more Apoptosis and cell proliferation are widely recognized to be important physiological processes which together maintain tissue homeostasis. The apoptotic and proliferative processes in 38 first trimester placentae were quantified using terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling (TUNEL) and an antibody against Ki-67 antigen, respectively. In 14 cases, the estimation of apoptotic index was repeated with sections stained with haematoxylin and eosin by identifying the morphological features of apoptosis. We found that the indices obtained by either method correlated well with each other although a lower rate was obtained with the haematoxylin and eosin stained sections. Apoptosis was found in clusters mainly in syncytiotrophoblasts in association with fibrinoid deposits while proliferating activity was limited to cytotrophoblasts and stromal cells. A significant inverse correlation was observed between the proliferative index and gestational age as well as the apoptotic index. While the extent of apoptosis decreased with advanced gestational age, the correlation was not statistically significant. These findings provide a potential explanation for villous remodelling during trophoblastic invasion in early pregnancy.
Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine, 2007
We compared the ultrasonographic parameters for endometrial receptivity between 2 consecutive in ... more We compared the ultrasonographic parameters for endometrial receptivity between 2 consecutive in vitro fertilization (IVF) cycles in the same patients. Patients who had undergone 2 in vitro fertilization cycles between November 2002 and December 2004 were recruited. A 3-dimensional ultrasonographic examination with power Doppler imaging was performed on the day of oocyte retrieval to determine the endometrial thickness, endometrial pattern, pulsatility and resistive indices of uterine vessels, endometrial volume, vascularization index, flow index, and vascularization flow index of endometrial and subendometrial regions. Of 662 patients, 95 (14.4%) underwent 2 consecutive cycles using the same stimulation regimen during the study period. There were no significant differences in these ultrasonographic parameters between the first and second cycles. The intraclass correlation coefficient (ICC) for endometrial volume was significantly higher than that of other ultrasonographic parameter...
Uterine arteriovenous malformation is a rare condition. Uterine artery embolization offers the po... more Uterine arteriovenous malformation is a rare condition. Uterine artery embolization offers the possibility of conservative management as opposed to the traditional hysterectomy. We report a case with recurrent uterine arteriovenous malformation confirmed by angiography and successfully treated with a second embolization procedure. A 33-year-old woman presented with heavy vaginal bleeding. The diagnosis of uterine arteriovenous malformation was suspected on Doppler ultrasonography and confirmed by angiography. The first embolization procedure was performed using polyvinyl alcohol and steel coils. Recurrence was diagnosed 1 year later with the same imaging techniques. The second embolization procedure was performed using histoacryl. The patient remained asymptomatic at 1-year of follow-up. Minimally invasive management is an option in recurrent uterine arteriovenous malformation.
Apoptosis and cell proliferation are widely recognized to be important physiological processes wh... more Apoptosis and cell proliferation are widely recognized to be important physiological processes which together maintain tissue homeostasis. The apoptotic and proliferative processes in 38 first trimester placentae were quantified using terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling (TUNEL) and an antibody against Ki-67 antigen, respectively. In 14 cases, the estimation of apoptotic index was repeated with sections stained with haematoxylin and eosin by identifying the morphological features of apoptosis. We found that the indices obtained by either method correlated well with each other although a lower rate was obtained with the haematoxylin and eosin stained sections. Apoptosis was found in clusters mainly in syncytiotrophoblasts in association with fibrinoid deposits while proliferating activity was limited to cytotrophoblasts and stromal cells. A significant inverse correlation was observed between the proliferative index and gestational age as well as the...
Oral communication abstracts and relate the results to studies on ultrasound diagnosis in view of... more Oral communication abstracts and relate the results to studies on ultrasound diagnosis in view of necessity of surgical intervention. Material and Methods: Two-hundred and thirty-four ovaries of postmenopausal women, who had died from non-gynaecological diseases, were examined prospectively and consecutively, by the pathologist (G.P. Blom), for cystic structures. The results were compared to recent ultrasound studies of adnexal cysts. Results: Ovarian cysts were found in 15.4% of the women. Paraovarian cysts were found in 4.7% of the women. All cysts were benign, except for one woman, who had bilateral serous cystadenoma of borderline type. Macroscopically the borderline cysts were multilocular with mean diameters of 60 mm and 15 mm, respectively. Conclusions: The results were in agreement with diagnostic ultrasound studies. The fact that we found benign ovarian and paraovarian cysts in 21.1% of the women should in our opinion make the gynecologists reconsider the need for surgical intervention in favor of follow-up.
Objectives: To evaluate the clinical significance and characteristics of intrauterine hematomas d... more Objectives: To evaluate the clinical significance and characteristics of intrauterine hematomas detected in the first trimester of pregnancy. Methods: A prospective study was designed to compare the obstetrical outcome in 43 pregnant women with intrauterine hematoma, who spontaneously aborted to 187 controls, who delivered after the hematoma was diagnosed. Statistical analysis was assessed by ÷2 analysis and two-tailed Fisher's exact test. Means of continuous variables were compared by two-tailed Student's t-test. Results: Smoking and multiparity were significantly greater in the abortion group. There was no significant difference with regard to maternal age, and medical history such as chronic hypertension (P = 0.66), gestational diabetes (P = 0.31), termination of pregnancy (P = 0.86), previous loss (P = 0.39) and perinatal death (P = 0.35). Retroplacental (P = 0.72) or subchorionic (P = 0.72) position of the hematoma was not significantly correlated with an increased risk for spontaneous abortion. The cervical (P = 0.004) and posterior (P = 0.002) location of the hematoma has significantly influenced the risk of abortion. The abortion rate was significantly greater in those who were spotting (P = 0.02), bleeding (P = 0.03) or crumping (P = 0.001), but not in those who were discharging (P = 0.1). Among patients having no symptoms the rate of abortion was significantly lower (P = 0.02). The volume ratio of the haematoma and the gestational sac was significantly greater in the abortion group (p < 0.001). Conclusion: Our study suggests that the presence and the characteristic of an intrauterine hematoma during the first trimester may identify a population of patients at increased risk for adverse pregnancy outcome.
There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndro... more There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndrome (PCOS). In addition to different diagnostic criteria used, the ethnic background of women with PCOS may affect the clinical, hormonal, and metabolic characteristics of this condition. We present here studies related to the clinical, hormonal, and metabolic characteristics and response to the treatment of PCOS in Asia, which may be different from those in Western countries. It is important to take into consideration the ethnic background of patients in future studies related to PCOS.
Journal of the Society for Gynecologic Investigation, 2006
To study the effects of green tea on body weight, and biochemical and hormonal profiles in obese ... more To study the effects of green tea on body weight, and biochemical and hormonal profiles in obese Chinese women with polycystic ovary syndrome (PCOS). Thirty-four obese Chinese women with PCOS were randomized into either treatment with green tea capsules or placebo for 3 months. The anthropometric measurements, and biochemical and hormonal profiles before and after treatment in each group were compared. The body weight of the green tea group decreased by a nonsignificant 2.4% after treatment; whereas the body weight, body mass index (BMI), and body fat content of the control group were significantly higher after 3 months. There were no differences in any of the hormone levels measured in either group. The biochemical profiles of the two groups were also similar except that there was a small but significant rise in the triglyceride level in the green tea group. Fewer patients in the green tea group remained amenorrhoeic, but this was not significantly different from the control group. Green tea supplementation did not significantly reduce body weight in obese women with PCOS, nor did it alter the glucose or lipid metabolism.
Journal of the Society for Gynecologic Investigation, 2005
To investigate changes in the uterine artery and ovarian stromal blood flow in relation to the ti... more To investigate changes in the uterine artery and ovarian stromal blood flow in relation to the time of the day after pituitary down-regulation during in vitro fertilization treatment. Thirteen women were recruited. The uterine artery blood flow was studied using pulsed color Doppler ultrasonography and the ovarian stromal blood flow was measured using three-dimensional power Doppler ultrasonography. Ultrasound scan examinations and blood pressure measurements were performed in the morning and evening. The diastolic and the mean arterial pressures were significantly higher in the evening. An increase in the uterine artery pulsatility index and resistance index in the evening was observed. The ovarian vascularization index, vascularization flow index, and right ovarian flow index were significantly lower in the evening. Despite the small sample size, we have demonstrated the presence of a diurnal change in uterine artery and ovarian stromal blood flow after pituitary down-regulation. Such changes may be related to the systemic change in the sympathetic system and hence vascular resistance. Future study regarding ovarian stromal blood flow should take into account the effect of the time of the day on the readings in order to avoid misleading interpretation of data.
Journal of the Society for Gynecologic Investigation, 2005
To investigate any change in the ovaries, including early follicular serum follicle-stimulating h... more To investigate any change in the ovaries, including early follicular serum follicle-stimulating hormone (FSH) level, total ovarian volume, total antral follicle count, and ovarian stromal blood flow, in patients who had undergone abdominal hysterectomy for benign conditions. Fifteen women with abdominal hysterectomy and conservation of ovaries for benign conditions and who were between 29 and 44 years old were recruited to undergo three-dimensional ultrasound examination with power Doppler to assess total ovarian volume, total antral follicle count, and vascularization index (VI), flow index (FI), and vascularization flow index (VFI) of ovarian stromal blood flow. Serum FSH, estradiol, and progesterone levels were checked on the same day. The results of the assessments were considered taken during the early follicular phase if the estradiol and progesterone levels were basal. Fifteen age-matched healthy women underwent the same assessments on the second day of menstruation. Women with hysterectomy had significantly elevated serum FSH level and lower ovarian stromal blood flow indices, including VI, FI, and VFI, as compared with healthy women. The total antral follicle count and the total ovarian volume were similar between the two groups. These changes may suggest altered ovarian function after hysterectomy.
Kong. His main research interests are assisted reproduction technology, assessment of ovarian res... more Kong. His main research interests are assisted reproduction technology, assessment of ovarian reserve and three-dimensional ultrasound in reproductive medicine. He has published about 100 papers in refereed journals.
Kong. His main research interests are assisted reproduction technology, assessment of ovarian res... more Kong. His main research interests are assisted reproduction technology, assessment of ovarian reserve and three-dimensional ultrasound in reproductive medicine. He has published about 100 papers in refereed journals.
This randomized trial compared the sequential use of letrozole and gonadotrophin (HMG) with HMG o... more This randomized trial compared the sequential use of letrozole and gonadotrophin (HMG) with HMG only in poor ovarian responders undergoing IVF. Patients with < four oocytes retrieved in previous IVF cycles or < 5 antral follicles were randomized to either letrozole for 5 days followed by HMG or HMG alone. 53 women were recruited. The letrozole group had significantly lower dosage of HMG (P < 0.001), shorter duration of HMG (P < 0.001) and fewer oocytes (P = 0.001) when compared to the control group. Live-birth rate was comparable with a significantly lower miscarriage rate in the letrozole group ((P = 0.038). Serum FSH concentrations were comparable in both groups except on Day 8, while estradiol concentrations were all significantly lower in the letrozole group from day 4. Follicular fluid concentrations of testosterone, androstenedione, FSH and AMH were significantly higher in the letrozole group (P = 0.009, P = 0.001, P = 0.046 and P =0.034 respectively). When compared to HMG alone, sequential use of letrozole and HMG in poor responders resulted in significantly lower total dosage and shorter duration of HMG, a comparable live-birth rate, a significantly lower miscarriage rate but a more favourable hormonal environment of follicular fluid.
To investigate Hong Kong couples&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;... more To investigate Hong Kong couples&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; attitudes and concerns about using preimplantation genetic diagnosis (PGD) and human leukocyte antigens (HLA) typing to conceive a disease-free and tissue-compatible &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;Saviour Child (SC)&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; to save an afflicted sibling. Two cohorts of Chinese couples, one with natural pregnancies and the other receiving in vitro fertilization (IVF) services, were studied using a structured questionnaire. Although most couples believed that embryos possess moral rights, they considered it acceptable to reproduce a donor child if it was safe for the child, and tissue transplantation was the only available treatment for the sick sibling. Most couples believed that the donor child would not suffer adverse physical or psychological effects but rather would gain positive psychological benefits, and opined that parents using PGD/HLA-typing suffer sacrificially for their children. In response to one specific question, one-third of the couples agreed to use the donor child as a lifetime organ donor and supported the use of PGD for non-medical gender selection. One-quarter were willing to reject PGD/HLA-typing because of its potential for non-medical genetic enhancement. Probably influenced by the Chinese tradition of strong familism, couples in Hong Kong generally show positive attitudes towards using PGD/HLA-typing to reproduce a &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;SC&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; to save a sibling affected with life-threatening diseases amenable to treatment with genetically compatible tissue.
To compare the efficacy of a nitric oxide donor (isosorbide mononitrate) and a prostaglandin E 1 ... more To compare the efficacy of a nitric oxide donor (isosorbide mononitrate) and a prostaglandin E 1 analogue (misoprostol) for cervical priming before suction termination of pregnancy. METHODS: This was a randomized, double blind, placebocontrolled trial. One hundred twenty-six healthy women requesting termination of pregnancy between 9 and 12 weeks' gestation were recruited. Women were randomized into three groups: control, isosorbide mononitrate, and misoprostol. All women were given moistened intravaginal study drugs (placebo, 40 mg of isosorbide mononitrate, or 400 g of misoprostol) 4-6 hours before suction evacuation. Side effects were assessed 3 hours after drug administration. The cervical dilatation and the cumulative force required to dilate the cervix to 8 mm were measured by a cervical tonometer before suction evacuation. Operative blood loss was measured after sieving off the products of gestation.
Previous studies analysing the incidences of mitochondrial DNA (mtDNA) deletions and mtDNA conten... more Previous studies analysing the incidences of mitochondrial DNA (mtDNA) deletions and mtDNA content in unfertilized oocytes in relation to donors' age have been controversial. The objective of the study was to compare these two parameters in unfertilized oocytes and relate them to the donors' age. Fifty-two women donated 155 unfertilized metaphase II (MII) oocytes. The incidence of 4977 bp deletion was 34.6%, and the mtDNA copy number was 598 350 ؎ 265 862. Women Ն35 years of age had a significantly higher incidence of 4977 bp deletion, lower mtDNA copy number, higher FSH level and poorer ovarian response when compared with younger women. The mtDNA copy number was negatively correlated with the donor's age. The higher incidence of mtDNA deletion and lower mtDNA copy number in older women suggested that these two parameters may reflect ovarian ageing.
Uploads
Papers by Carina Chan