Vaginal delivery of second twins: factors predictive of failure and adverse perinatal outcomes

INTRODUCTION

This study was performed to explore factors associated with adverse perinatal outcomes for second twins and to identify predictive factors for successful vaginal delivery of the second twin after vaginal delivery of the first twin.

METHODS

This 10-year retrospective study included 231 cases of twin pregnancies in which vaginal delivery of the second twin was attempted after vaginal delivery of the first twin. The relationships of obstetric characteristics with the composite adverse perinatal outcome of the second twin were analysed. Predictive factors for successful vaginal delivery of the second twin were also explored.

RESULTS

Gestational age <32 weeks was the only independent risk factor for the composite adverse perinatal outcome and neonatal intensive care unit admission for the second twin. A longer inter-twin delivery interval was associated with greater risk of caesarean delivery of the second twin, but it did not increase the risk of an adverse perinatal outcome. Non-vertex presentation of the second twin at delivery was independently associated with caesarean delivery (9.0% vs 2.0%, P=0.03). For second twins in breech presentation, caesarean delivery was associated with the presence of less experienced birth attendants.

CONCLUSION

Among second twins born to mothers who had attempted vaginal delivery, adverse perinatal outcomes were mainly related to prematurity. The presence of more experienced birth attendants may contribute to successful vaginal delivery of the second twin, particularly for twins in non-vertex presentation.

Non-visualisation of fetal gallbladder in a Chinese cohort

INTRODUCTION

Non-visualisation of fetal gallbladder (NVFGB) is associated with chromosomal abnormalities, biliary atresia, cystic fibrosis, and gallbladder agenesis in Caucasian fetuses. We investigated the outcomes of fetuses with NVFGB in a Chinese cohort.

METHODS

This retrospective analysis included cases of NVFGB among Chinese pregnant women at five public fetal medicine clinics in Hong Kong from 2012 to 2019. We compared the incidences of subsequent gallbladder visualisation, chromosomal abnormalities, biliary atresia, cystic fibrosis, and gallbladder agenesis between cases of isolated NVFGB and cases of non-isolated NVFGB.

RESULTS

Among 19 cases of NVFGB detected at a median gestational age of 21.3 weeks (interquartile range, 20.0-22.3 weeks), 10 (52.6%) were isolated and nine (47.4%) were non-isolated. Eleven (58.0%) cases had transient non-visualisation, four (21.0%) had gallbladder agenesis, three (15.8%) had chromosomal abnormalities (trisomy 18, trisomy 21, and 22q11.2 microduplication), one (5.2%) had biliary atresia, and none had cystic fibrosis. The incidence of serious conditions was significantly higher in the non-isolated group than in the isolated group (44.4% vs 0%; P=0.029); all three cases with chromosomal abnormalities and the only case of biliary atresia were in the non-isolated group, while all four cases with gallbladder agenesis were in the isolated group. The incidences of transient non-visualisation were similar (55.6% vs 60.0%; P=1.000).

CONCLUSION

Isolated NVFGB is often transient or related to gallbladder agenesis. While investigations for chromosomal abnormalities and biliary atresia are reasonable in cases of NVFGB, testing for cystic fibrosis may be unnecessary in Chinese fetuses unless the NVFGB is associated with consistent ultrasound features, significant family history, or consanguinity.

Prenatal presentation in two fetuses with features of Beckwith Wiedemann syndrome-An unexpected diagnosis of androgenetic chimera and its clinical implications

Beckwith Wiedemann Syndrome (BWS, OMIM 130650) is an imprinting disorder that may present antenatally with a constellation of sonographic features namely polyhydramnios, macrosomia, macroglossia, omphalocele, placental mesenchymal dysplasia, cardiomegaly, nephromegaly, fetal hydrops, and other rare anomalies. Paternal uniparental disomy in chromosome 11p15 imprinting region accounts for 20% of all BWS, and 8% among those were due to genome-wide paternal uniparental disomy (GWpUPD). GWpUPD is a rare condition and usually results in prenatal lethality. The 31 liveborns reported in the literature demonstrate female predominance in surviving GWpUPD. Here, we reported two prenatal cases which initially presented with features suggestive of BWS, which subsequently were confirmed to have GWpUPD. Further trio SNP genotyping analysis using SNP-based chromosomal microarray revealed androgenetic biparental chimera as the underlying cause. Finally, we highlighted the importance of recognizing GWpUPD as a possible cause in a fetus presenting with BWS phenotype, as it carried a different disease prognosis, tumor predisposition, manifestations of other imprinting disorders, and possibility in unmasking autosomal recessive disorders from the paternal alleles.

Adaptive risk prediction system with incremental and transfer learning

Currently, popular methods for prenatal risk assessment of fetal aneuploidies are based on multivariate probabilistic modelling, that are built on decades of scientific research and large-scale multi-center clinical studies. These static models that are deployed to screening labs are rarely updated or adapted to local population characteristics. In this article, we propose an adaptive risk prediction system or ARPS, which considers these changing characteristics and automatically deploys updated risk models. 8 years of real-life Down syndrome screening data was used to firstly develop a distribution shift detection method that captures significant changes in the patient population and secondly a probabilistic risk modelling system that adapts to new data when these changes are detected. Various candidate systems that utilize transfer -and incremental learning that implement different levels of plasticity were tested. Distribution shift detection using a windowed approach provides a computationally less expensive alternative to fitting models at every data block step while not sacrificing performance. This was possible when utilizing transfer learning. Deploying an ARPS to a lab requires careful consideration of the parameters regarding the distribution shift detection and model updating, as they are affected by lab throughput and the incidence of the screened rare disorder. When this is done, ARPS could be also utilized for other population screening problems. We demonstrate with a large real-life dataset that our best performing novel Incremental-Learning-Population-to-Population-Transfer-Learning design can achieve on par prediction performance without human intervention, when compared to a deployed risk screening algorithm that has been manually updated over several years.

Hong Kong Geriatrics Society and Hong Kong Urological Association consensus on personalised management of male lower urinary tract symptoms in the era of multiple co-morbidities and polypharmacy

Lower urinary tract symptoms (LUTS) are common complaints of adult men. Benign prostatic hyperplasia (BPH) represents the most common underlying cause. As the incidence of BPH increases with age, and pharmacological treatment is a major part of the disease's management, the majority of patients with LUTS are managed by primary care practitioners. There are circumstances in which specialist care by urologists or geriatricians is required, such as failure of medical treatment, adverse effects from medical treatment, or complications from BPH. Referral choices can be confusing to patients and even practitioners in different specialties under such circumstances. There is currently no local consensus about the diagnosis, medical management, or referral mechanism of patients with BPH. A workgroup was formed by members of The Hong Kong Geriatrics Society (HKGS) and the Hong Kong Urological Association (HKUA) to review evidence for the diagnosis and medical treatment of LUTS. A consensus was reached by HKGS and HKUA on an algorithm for the flow of male LUTS care and the use of uroselective alpha blockers, antimuscarinics, beta-3 adrenoceptor agonists, and 5α-reductase inhibitors in the primary care setting. This consensus by HKGS and HKUA provides a new management paradigm of male LUTS.

Successful management of a second trimester cesarean scar pregnancy using local methotrexate injection

.

Severe Intrapartum Asphyxia from Subamniotic Hemorrhage

Subamniotic hemorrhage results from rupture of chorionic vessels near the cord insertion. In the literature, it has never been a major cause for severe intrapartum complications. We report the first case of acute massive subamniotic hemorrhage intrapartum resulting in severe perinatal asphyxia.

Association between pregnancy-associated plasma protein-A levels in the first trimester and gestational diabetes mellitus in Chinese women

INTRODUCTION

Several studies have shown that women with pre-existing diabetes mellitus have significantly lower pregnancy-associated plasma protein-A levels than those without. This study aimed to evaluate whether first-trimester pregnancy-associated plasma protein-A multiple of median is associated with gestational diabetes mellitus in Chinese pregnant women.

METHODS

This prospectively collected case series was conducted in a regional hospital in Hong Kong. All consecutive Chinese women with a singleton pregnancy who attended the hospital for their first antenatal visit (before 14 weeks' gestation) from April to July 2014 were included. Pregnancy-associated plasma protein-A multiple of median was compared between the gestational diabetic (especially for early-onset gestational diabetes) and non-diabetic groups. The correlation between pregnancy-associated plasma protein-A level and glycosylated haemoglobin level in women with gestational diabetes was also examined.

RESULTS

Of the 520 women recruited, gestational diabetes was diagnosed in 169 (32.5%). Among them, 43 (25.4%) had an early diagnosis, and 167 (98.8%) with the disease were managed by diet alone. The gestational diabetic group did not differ significantly to the non-diabetic group in pregnancy-associated plasma protein-A (0.97 vs 0.99, P=0.40) or free β-human chorionic gonadotrophin multiple of median (1.05 vs 1.02, P=0.29). Compared with the non-gestational diabetic group, women with early diagnosis of gestational diabetes had a non-significant reduction in pregnancy-associated plasma protein-A multiple of median (median, interquartile range: 0.86, 0.57-1.23 vs 0.99, 0.67-1.44; P=0.11). Pregnancy-associated plasma protein-A and glycosylated haemoglobin levels were not correlated in women with gestational diabetes (r=0.027; P=0.74).

CONCLUSIONS

Chinese women with non-insulin-dependent gestational diabetes did not exhibit significant changes to pregnancy-associated plasma protein-A multiple of median nor a correlation between pregnancy-associated plasma protein-A with glycosylated haemoglobin levels. Pregnancy-associated plasma protein-A multiple of median was not predictive of non-insulin-dependent gestational diabetes or early onset of gestational diabetes. There was a high prevalence of gestational diabetes in the Chinese population.

Indications for and pregnancy outcomes of cervical cerclage: 11-year comparison of patients undergoing history-indicated, ultrasound-indicated, or rescue cerclage

OBJECTIVES

To review and compare pregnancy outcomes of patients undergoing history-indicated, ultrasound-indicated, or rescue cerclage.

DESIGN

Case series with internal comparison.

SETTING

A regional obstetric unit in Hong Kong.

PATIENTS

Women undergoing cervical cerclage at Kwong Wah Hospital between 1 January 2001 and 31 December 2011.

INTERVENTIONS

Cervical cerclage.

MAIN OUTCOME MEASURES

Pregnancy outcomes including miscarriage, gestational age at delivery, birth weight, and duration of pregnancy prolongation.

RESULTS

Overall, 47 patients were included. Nine (19.1%) pregnancies resulted in miscarriage. The median gestational age at delivery was 35.7 weeks. Among the 23 patients who had history-indicated cerclage, only four (17.4%) had three or more previous second-trimester miscarriages or preterm deliveries. Among the 15 patients who had ultrasound-indicated cerclage, preoperative cervical length of ≤1.5 cm was associated with shorter prolongation of pregnancy, compared with that of >1.5 cm (median, 12.1 vs 18.4 weeks; P=0.009). Among the nine women who had rescue cerclage, those who underwent the procedure before 20 weeks of gestation delivered earlier than those underwent cerclage later (median, 22.5 vs 34.1 weeks; P=0.048).

CONCLUSIONS

Patients eligible for the Royal College of Obstetricians and Gynaecologists-recommended history-indicated cerclage remain few. The majority of patients may benefit from serial ultrasound monitoring of cervical length with or without ultrasound-indicated cerclage.

Double balloon catheter for induction of labour in Chinese women with previous caesarean section: one-year experience and literature review

OBJECTIVES

To evaluate the efficacy and safety of double balloon catheter for induction of labour in Chinese women with one previous caesarean section and unfavourable cervix at term.

DESIGN

Retrospective cohort study.

SETTING

A regional hospital in Hong Kong.

PATIENTS

Women with previous caesarean delivery requiring induction of labour at term and with an unfavourable cervix from May 2013 to April 2014.

MAJOR OUTCOME MEASURES

Primary outcome was to assess rate of successful vaginal delivery (spontaneous or instrument-assisted) using double balloon catheter. Secondary outcomes were double balloon catheter induction-to-delivery and removal-to-delivery interval; cervical score improvement; oxytocin augmentation; maternal or fetal complications during cervical ripening, intrapartum and postpartum period; and risk factors associated with unsuccessful induction.

RESULTS

All 24 Chinese women tolerated double balloon catheter well. After double balloon catheter expulsion or removal, the cervix successfully ripened in 18 (75%) cases. The improvement in Bishop score 3 (interquartile range, 2-4) was statistically significant (P<0.001). Overall, 18 (75%) cases were delivered vaginally. The median insertion-to-delivery and removal-to-delivery intervals were 19 (interquartile range, 13.4-23.0) hours and 6.9 (interquartile range, 4.1-10.8) hours, respectively. Compared with cases without, the interval to delivery was statistically significantly shorter in those with spontaneous balloon expulsion or spontaneous membrane rupture during ripening (7.8 vs 3.0 hours; P=0.025). There were no major maternal or neonatal complications. The only factor significantly associated with failed vaginal birth after caesarean was previous caesarean section for failure to progress (P<0.001).

CONCLUSIONS

This is the first study using double balloon catheter for induction of labour in Asian Chinese women with previous caesarean section. Using double balloon catheter, we achieved a vaginal birth after caesarean rate of 75% without major complications.

Social obstetrics: non-local expectant mothers admitted through accident and emergency department in a public hospital in Hong Kong

OBJECTIVES

To review the pregnancy outcomes of non-booked, non-local pregnant women delivering in Kwong Wah Hospital via admission to the Accident and Emergency Department 1 year after the announcement by the Hospital Authority to stop antenatal booking for non-eligible persons; and to perform a literature review of local studies about non-eligible person deliveries over the last decade.

DESIGN

Case series.

SETTING

A public hospital in Hong Kong.

PARTICIPANTS

All women who held the People's Republic of China passport or the two-way permit and those non-eligible persons whose spouses were Hong Kong Identity Card holders, who delivered in Kwong Wah Hospital from 1 April 2011 to 31 March 2012.

RESULTS

Overall, 219 women who were non-eligible persons delivered 221 live births during the study period. Compared with the annual statistics of Kwong Wah Hospital in 2011, non-local mothers were of higher parity; more likely to have hypertensive disease (including pre-eclamptic toxaemia), preterm deliveries (ie at <37 weeks), babies needing admission to the special care baby unit, and macrosomic babies (ie weighing >4.0 kg). The rates of induction of labour and caesarean section were lower in this group. There was no significant difference in the maternal and neonatal outcomes between women who had no booking and those who had a booking in another Hospital Authority or private hospital. There were many incidents of near-miss obstetric complications or suboptimally managed obstetric conditions due to lack of well-structured and continuous antenatal care in this group of non-eligible persons.

CONCLUSION

Non-eligible person delivering babies in Hong Kong has become a social obstetrics phenomenon. Despite the introduction of policies, reduction in the number of deliveries (quantity) did not improve the obstetric outcomes (quality). Health care professionals should continue to be prepared for managing the potential near-miss clinical complications in this group of 'travelling mothers'.

Intensive care unit admission of obstetric cases: a single centre experience with contemporary update

OBJECTIVES. To review the characteristics of a series of obstetric patients admitted to the intensive care unit in a regional hospital in 2006-2010, to compare them with those of a similar series reported from the same hospital in 1989-1995 and a series reported from another regional hospital in 1998-2007. DESIGN. Retrospective case series. SETTING. A regional hospital in Hong Kong. PATIENTS. Obstetric patients admitted to the Intensive Care Unit of Kwong Wah Hospital from 1 January 2006 to 31 December 2010. RESULTS. From 2006 to 2010, there were 67 such patients admitted to the intensive care unit (0.23% of total maternities and 2.34% of total intensive care unit admission), which was a higher incidence than reported in two other local studies. As in the latter studies, the majority were admitted postpartum (n=65, 97%), with postpartum haemorrhage (n=39, 58%) being the commonest cause followed by pre-eclampsia/eclampsia (n=17, 25%). In the current study, significantly more patients had had elective caesarean sections for placenta praevia but fewer had had a hysterectomy. The duration of intensive care unit stay was shorter (mean, 1.8 days) with fewer invasive procedures performed than in the two previous studies, but maternal and neonatal mortality was similar (3% and 6%, respectively). CONCLUSION. Postpartum haemorrhage and pregnancy-induced hypertension were still the most common reasons for intensive care unit admission. There was an increasing trend of intensive care unit admissions following elective caesarean section for placenta praevia and for early aggressive intervention of pre-eclampsia. Maternal mortality remained low but had not decreased. The intensive care unit admission rate by itself might not be a helpful indicator of obstetric performance.

Factors influencing the mode of delivery and associated pregnancy outcomes for twins: a retrospective cohort study in a public hospital

OBJECTIVES

To determine current trends for different modes of delivery in twin pregnancies, factors affecting the mode of delivery, and associated outcomes.

DESIGN

Retrospective cohort study.

SETTING

A public hospital in Hong Kong.

PARTICIPANTS

All twin pregnancies booked at Kwong Wah Hospital during a 3-year period from 1 April 2006 to 31 March 2009.

RESULTS

Of 197 sets of twins, 35 (18%) were delivered vaginally and 162 (82%) by caesarean section (47% were emergencies and 53% elective). In all, 32 (37%) of the elective and 21 (28%) of the emergency caesarean sections were in response to maternal requests. Vaginal delivery was more common in mothers with a history of vaginal delivery and monochorionic diamniotic twins. Women who conceived by assisted reproduction or those who had a tertiary education were more likely to deliver by caesarean section. The type of conception and the presentation of the second twin were statistically significant factors affecting maternal choice on the mode of delivery. Maternal age did not affect the choice of delivery mode. Except for the higher frequency of sepsis and cord blood acidosis in second twins delivered vaginally, there were no significant differences in neonatal morbidity between the groups that attempted vaginal delivery or requested caesarean sections. All the women who had compression sutures or hysterectomy to control massive postpartum haemorrhage were delivered by caesarean section.

CONCLUSION

A high caesarean section rate observed in our cohort was associated with maternal requests for this mode of delivery. The type of conception and the presentation of the second twin were statistically significant factors affecting maternal choice on mode of delivery. Women's requests for caesarean delivery out of the concern for their babies are not supported by current evidence. In response to a woman with a twin pregnancy requesting caesarean delivery, the pros and cons of vaginal deliveries and caesarean sections should be fully explained before the woman's autonomy is respected.

Predictors of successful outcomes after external cephalic version in singleton term breech pregnancies: a nine-year historical cohort study

OBJECTIVE

To study the success rate, predictors for success, and pregnancy outcomes after external cephalic version.

DESIGN

Historical cohort study.

SETTING

Regional hospital, Hong Kong.

PATIENTS

All women who had singleton term breech pregnancies at term and opted for external cephalic version during 2001 and 2009. Their demographic data, clinical and ultrasound findings, procedure details, complications, and delivery outcomes were analysed.

MAIN OUTCOME MEASURES

Predictive factors for successful external cephalic version.

RESULTS

A total of 209 external cephalic versions were performed during the 9-year period. The success rate was 63% (75% for multiparous and 53% for nulliparous women). There was no significant complication. On univariate analysis, predictors of successful external cephalic version were: multiparity, unengaged presenting part, higher amniotic fluid index (≥ 10 cm), thin abdominal wall, low uterine tone, and easily palpable fetal head (subjective assessment by practitioners before external cephalic version). On multivariate analysis, only multiparity, non-engagement of the fetal buttock and thin maternal abdomen were associated with successful external cephalic version. In all, 69% of those who had successful external cephalic version succeeded in the first roll (P<0.001), and 82% of the women with successful external cephalic versions had vaginal deliveries (93% in multiparous and 69% in nulliparous women). Uptake rate of external cephalic version was studied in the latter part of the study period (2006-2009). Whilst 735 women were eligible for external cephalic version, 131 women chose to have the procedure resulting in an uptake rate of 18%.

CONCLUSION

External cephalic version was effective in reducing breech presentations at term and corresponding caesarean section rates, but the uptake rate was low. Further work should address the barriers to the low acceptance of external cephalic version. The results of this study could encourage women to opt for external cephalic version.

Handwriting characteristics among secondary students with and without physical disabilities: a study with a computerized tool

The purpose of the present study was to investigate the handwriting characteristics of secondary school students with and without physical disabilities (PD). With the use of a computerized Chinese Handwriting Assessment Tool (CHAT), it was made possible to objectively assess and analyze in detail the handwriting characteristics of individual students. Fifty participants (age range: 15-19-years-old) were recruited from one mainstream secondary school and 20 participants (age range: 17-24-years-old) were recruited from two secondary schools for students with PD. They were asked to perform three consecutive handwriting tasks: copying 90 characters using the computerized CHAT, an English passage copying task, and a Chinese passage copying task. The data indicated that students with PD were significantly slower in copying both Chinese and English characters in passages when compared to the typical students. Significant differences in the measures of writing speed, air/ground time ratio, standard deviation of speed, standard deviation of size per character, and number of stroke errors measured by the CHAT were found between the two groups of students. Further analysis on the data of typical students indicated no significant difference in handwriting speed among students of different classes (i.e. arts or science) on copying Chinese and English passages, and on individual Chinese words (from CHAT). The academic results of students also showed no significant correlation with their handwriting speed measured by the three writing tasks. To conclude, the CHAT system was able to identify a number of characteristics of handwriting on students with and without PD. It was suggested that the CHAT should further be developed into an objective evaluation tool to explore the handwriting characteristics of the students with a wider range of disabilities in the future, and to make recommendations to arrange special examination arrangements (SEA) for students with physical disabilities or other special needs.

The preparedness of Hong Kong medical students towards advance directives and end-of-life issues

OBJECTIVES

To explore the preparedness of medical students towards advance directives and related end-of-life issues, and to examine background factors such as knowledge, attitudes, and experience concerning advance directives and related end-of-life issues.

METHODS

In 2007, 448 medical students in years 3 to 5 were surveyed at the Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong. Their knowledge, attitudes, and experiences of advance directives and related end-of-life issues, and their self-perceived preparedness to discuss these matters with patients were evaluated.

RESULTS

A total of 220 (49%) of the eligible students responded, of whom 79% supported the use of advance directives. Only 65 (30%) students were certain of what advance directives meant and 198 (90%) students felt that their knowledge of advance directives was inadequate. Also, 197 (90%) students felt unprepared about advance directives and end-of-life issues. Factors associated with positive attitude towards advance directives included religion and knowledge. No factors were found to be associated with self-perceived preparedness towards advance directives or end-of-life issues.

CONCLUSIONS

Most of the medical students surveyed demonstrated a positive attitude towards advance directives and recognised the importance of advance directives. However, they felt that they were unprepared and lacking in knowledge and experience of advance directives and end-of-life issues. Wider range and more depth of education is needed to better equip medical students for future practice.

Obstetric cholestasis in Hong Kong--local experience with eight consecutive cases

Obstetric cholestasis is associated with maternal morbidity and adverse foetal outcomes. No information on local incidence is available. We present our experience with eight consecutive cases of obstetric cholestasis diagnosed between January 2003 and December 2005 in a regional hospital in Hong Kong. Three patients presented with pruritus without rash, three with impaired liver function, and two with elevated blood pressure postpartum. Meconium-stained liquor was present in five patients and four had spontaneous preterm delivery (between 34 and 36 weeks). The higher the bile acid level, the more marked the prematurity (correlation coefficient, -0.771; P=0.025). All those presenting with itchiness delivered preterm. Two patients developed pre-eclampsia. The rates of labour induction and abdominal delivery were both 38%. Heightened awareness among clinicians is required to recognise patients with obstetric cholestasis. Affected pregnancies are associated with meconium passage and prematurity. In our locality, affected women may also have an increased risk of pre-eclampsia. In affected women, the bile acid level is useful in assessing the risk of prematurity.

Sublingual misoprostol compared to artificial rupture of membranes plus oxytocin infusion for labour induction in nulliparous women with a favourable cervix at term

OBJECTIVES

To compare the efficacy of labour induction using sublingual misoprostol versus combined artificial rupture of membranes and oxytocin infusion for nulliparous women with a favourable cervix at term.

DESIGN

Open randomised controlled trial.

SETTING

Regional hospital, Hong Kong.

PATIENTS

Fifty nulliparous women with a favourable cervix (Bishop score 6 or more) at term and indications for labour induction.

INTERVENTIONS

With their informed consent, 100 eligible women were to be randomised to receive either sublingual misoprostol 50 micrograms every 4 hours for up to five doses or oxytocin infusion after artificial rupture of membranes. Interim analysis was planned at a sample size of 50.

MAIN OUTCOME MEASURES

Vaginal delivery within 24 hours of induction.

RESULTS

The study was terminated when interim analysis of the first 50 recruits showed that a significantly smaller proportion of misoprostol-treated women delivered vaginally within 24 hours of induction than in the conventional treatment group (68% vs 100%; relative risk, 0.68; 95% confidence interval, 0.51-0.91; P=0.009), although comparable numbers of women eventually delivered vaginally. The mean induction to vaginal delivery interval was 4.5 hours longer in the misoprostol group (P=0.027). After misoprostol treatment, all women went into labour. Forty percent of them delivered without oxytocin. There was no significant difference in uterine hyperstimulation rate, operative delivery rate, and neonatal outcomes. Maternal satisfaction was higher in the misoprostol group (92% vs 60%; relative risk, 1.53; 95% confidence interval, 1.09-2.16; P=0.008).

CONCLUSIONS

Despite being well accepted by women, labour induction using this regimen of sublingual misoprostol is less effective in achieving vaginal delivery within 24 hours.

Chromosomal abnormalities and FMR1 gene premutation in Chinese women with premature menopause

OBJECTIVE

To study the prevalence of chromosomal abnormalities and FMR1 gene premutation in Chinese women with premature menopause in Hong Kong.

DESIGN

Retrospective study.

SETTING

Clinical Genetic Service, Hong Kong.

PARTICIPANTS

Chinese women with premature menopause referred for cytogenetic study from January 1983 to November 2003.

MAIN OUTCOME MEASURES

Chromosomal abnormalities, FMR1 gene premutation.

RESULTS

Chromosomal abnormalities were present in 15.6% of Chinese women who suffered premature menopause. X-chromosome abnormality was involved in over 80% of cases. FMR1 gene premutation was present in 0.86% of 116 cases screened for this abnormality. The predominance of X-chromosome abnormality accounted for the shorter stature, younger menopausal age, and higher prevalence of dysmorphic features among the cytogenetically abnormal patients. However, on logistic regression, no clinical feature was significantly correlated with cytogenetic abnormality.

CONCLUSIONS

The prevalence of chromosomal abnormalities among Hong Kong Chinese women who suffer premature menopause was comparable with that of Caucasian and Chinese populations elsewhere. Because clinical features are poor predictors of cytogenetic abnormality, a pragmatic approach to screening is advocated. The carrier rate of fragile X premutation in these women appeared lower than that of Caucasians. Nevertheless, a search for FMR1 gene premutation, in addition to conventional chromosomal study, has important implication for prenatal diagnosis and fertility management for the extended family.