Stephen Sik Hung Suen

Knowledge on hepatitis B infection among pregnant women in a high endemicity area

OBJECTIVE To assess the knowledge on hepatitis B virus (HBV) infection and associated factors among expectant mothers in an endemic region. METHODS A questionnaire was administered to pregnant Chinese women (n=1623) attending the antenatal clinic to examine their knowledge on HBV infection, and correlating this with socio-demographic, medical and obstetric factors. RESULTS Independent factors associated with insufficient reduced HBV knowledge include women outside the healthcare sector, lower education level, and no previous HBV testing. The majority of respondents could provide correct responses about the common aspects of HBV infection, including screening, blood-borne and perinatal transmissions, prevention by vaccination, and sequelae of HBV infection, but 47.1% did not know that HBV is transmissible by sexual intercourse. Over 75% respondents misunderstood the fact that HBV cannot be transmitted through food, or prevented by a balanced life style and nutrition. CONCLUSIONS Misconceptions about HBV transmission are still common among the obstetric population, and the provision of appropriate and correct information is warranted to improve further the control of HBV infection to the target group. PRACTICE IMPLICATIONS Appropriate emphasis should be given to educating the general population about horizontal transmission of HBV.

Determinants of hepatitis B vaccine uptake among pregnant Chinese women in Hong Kong.

To determine the prevalence of a history of hepatitis B vaccination among pregnant Chinese women in Hong Kong, and to identify factors associated with vaccine uptake at their own expense.

External cephalic version does not increase the risk of intra-uterine death: a 17-year experience and literature review

Objective: To assess the risk of intra-uterine death (IUD) after external cephalic version (ECV). Methods: In this retrospective cohort study, 1078 consecutive ECVs performed between January 1994 and March 2011 in an University teaching hospital were extracted from the computerized database to examine the risk of IUD after ECV. Results: A total of 1078 consecutive ECVs were performed over the study period. The overall successful rate was 72.8%, the successful rate was 63.1% in nulliparous and 82.7% in multiparous, respectively (p < 0.001). There was no IUD identified within 24 h after the procedure and there was only one case of IUD (0.09%) that occurred 4 weeks after an uncomplicated ECV. Conclusions: ECV is a safe procedure that does not increase the risk of IUD within and after 24 h of enrolment irrespective of outcome of ECV. Our findings have important clinical implication in terms of patient counseling regarding the decision on term breech management.

Universal rubella vaccination programme and maternal rubella immune status: A tale of two systems

Maternal rubella status was compared between local residents with non-residents who delivered in our hospital during 1998-2008. Among the 60,822 women, non-immunity was more common in the non-residents (19.9% versus 8.1%, P<0.001). Significant difference and positive correlation with age and parity were found for both groups, but a significant inverse correlation with year-of-birth was found only in the residents. Regression analysis confirmed that birth after 1970 was associated with reduced odds of non-immunity, which indicated that the rubella vaccination programme, introduced since 1978, has succeeded in reducing the incidence of non-immunity to <5% in the youngest generation.

Deficient Knowledge on Hepatitis B Infection in Pregnant Women and Prevalence of Hepatitis B Surface Antigen Carriage in an Endemic Area: A Review

Hepatitis B infection is a major global health problem. Vertical transmission is the commonest route of spreading hepatitis B virus (HBV) in many endemic areas. In order to control such transmission in Hong Kong, neonatal immunization programme was implemented for more than two decades. A declining prevalence of HBV infection was expected. However, the prevalence remained unabated at around 10% in recent studies. We suspect that one of the explanations of this persistent high prevalence is deficient knowledge on infection with the HBV and its prevention. Our paper gives an overview of the knowledge on HBV infection among Chinese population in both high and low endemic areas and discusses the potential factors that influenced the knowledge on as well as the implication of the sources of information for HBV infection, which was not addressed in previous studies.

Maternal understanding of commercial cord blood storage for their offspring – a survey among pregnant women in Hong Kong

Objective. To assess the knowledge on commercial cord blood banking (CCBB) among pregnant women. Design. Cross‐sectional survey. Setting. Antenatal clinics of two major public maternity units in Hong Kong. Population. Pregnant women. Methods. Self‐administered questionnaire. Main outcome measures. The survey explored knowledge about the use of self‐stored umbilical cord blood (UCB) stem cells and attitude towards CCBB. Results. Of the 2 000 women recruited, 1 866 (93.3%) completed the questionnaire. The majority (78.2%) had no idea that there was the chance of using self‐stored stem cells. Moreover, most of the respondents were unclear about which diseases other than leukemia are amenable to treatment with UCB stem cells in general. Only 20.3% of women knew that stem cells are available from the Red Cross in case their children need hematopoietic cell transplantation. Conclusions. The results of this study revealed inadequate knowledge on UCB stem cell banking and its applications among most of our pregnant women. The government and clinicians should combine efforts to provide accurate information on utilization of UCB stem cells during antenatal care.

Has improved health care provision impacted on the obstetric outcome in teenage women

Objective: To determine the obstetric outcome in teenage women managed in the recent decade with easily accessible health care provision. Methods: In a retrospective cohort study, maternal demographics, underlying medical conditions, obstetric complications, preterm birth, type of labor, mode of delivery, and perinatal mortality were compared between 1505 women aged ≤19 years (study group) with 10,320 women aged 20–24 years (comparison group), who were carrying singleton pregnancies beyond 24 weeks of gestation and managed in our hospital between January 1998 and June 2008. Results: The study and comparison groups accounted for 2.2% and 15.1% respectively of the total deliveries. Despite comparable health status and rates of other obstetric complications, teenage women was associated with birth <34 weeks (aOR 2.45, 95% CI 1.67–3.60), birth at 34–36 weeks (aOR 2.13, 95% CI 1.71–2.65), and reduced instrumental vaginal (aOR 0.62, 95% CI 0.50–0.77) and caesarean (aOR 0.79, 95% CI 0.64–0.97) delivery, without increase in perinatal mortality. Conclusions: Teenage women had increased preterm birth, despite improved health care provision, nutrition, and similar incidence of other obstetric complications, but the obstetric and perinatal outcome remained favorable.

Is there Seasonality in the Incidence of Oral-Facial Clefts?

Abstract Objective: To determine if seasonal variation in the incidence of oral-facial clefts exists in the Hong Kong Chinese population. Methods: Cases of non-syndromal oral-facial clefts identified from the Prenatal Diagnostic Clinic database from 2002-2009, and total births from our departmental statistics during this period, were used to calculate the averaged month-of-conception incidence for overall cases and individual categories of clefts, including cleft lip (CL), cleft palate (CP), cleft lip with/without cleft palate (CL+/-CP), and cleft lip with cleft palate (CLP). Results: There were 59 eligible cases (1.21/1000 births), including 25 CL, 12 CP and 22 CLP cases. The peak incidence was in February (1.96/1000 births) and the lowest in September (0.67/1000 births). There was significant inverse correlation with the months from winter (December) to autumn (November) for all categories except for CP. When analysed by seasons, significant inverse correlation from winter to autumn was observed for all categories, and significant differences in incidence was demonstrated for CL+/-CP and CL. Conclusions: The seasonality in the incidence of oral-facial clefts found in this study suggested that environmental factors are probably involved, which would have accounted for the reported seasonal variations and geographical and racial differences in the incidence in the literature.

Seroprevalence of varicella zoster virus among pregnant women in Hong Kong: Comparison with self-reported history

OBJECTIVE To compare seroprevalence (serum IgG titre) with self-reported history of varicella zoster virus (VZV) infection among pregnant women in Hong Kong. METHODS Pregnant women undergoing first trimester Down screening over a 3-months period were recruited for the study. RESULTS Positive immunity was found in 477 (95.4%) of the 500 recruited women, and those with positive, negative, or uncertain history of infection had similarly high seroprevalence (96.4, 90.5, 95.9% respectively). The mean age of infection from self-recalled history was 8.61 (SD 4.69) years, and only 3% recalled infection after age 18. Insufficient knowledge on the disease and vaccination was demonstrated. CONCLUSIONS Despite the absence of a routine vaccination programme, VZV immunity was high among pregnant women, the majority being infected during childhood and infection above age 18 was very rare. Hence, universal antenatal screening or vaccination for all women in the reproductive age would not be cost-effective in Hong Kong.

Do Prior Contraceptive Methods Impact Maternal Carriage in Patients with Hepatitis B

Background Hepatitis B virus (HBV) infection is highly endemic in many Asian countries. Objectives We examined whether prior contraceptive methods and sexual behavioral factors impact maternal HBV carriage in an obstetric population. Patients and Methods For this study, pregnant women were considered to be representative of the sexually active and fertile female population. Contraceptive methods used prior to the index pregnancy were examined in 1283 pregnant Chinese women attending an antenatal clinic using a self-administered questionnaire, and correlated with the maternal HBV status determined using routine antenatal screening. Results In our study, 111 (8.7%) women were infected with HBV and there was no difference in the incidence of male condom usage between HBV-positive (88.3%) and HBV-negative (83.5%) women. No contraceptive method was associated with a reduced incidence of maternal HBV carriage, except for coitus interruptus. In multivariate analysis, only multiparity (adjusted odds ratio [aOR], 1.62) and more than 1 sexual partner (aOR, 1.57) were independent factors associated with maternal HBV carriage. Conclusions Contraceptive use played only a minimal role in preventing sexual transmission of HBV infection within the sexually active female population in an endemic area.