Acceptability of different mechanisms of action of contraception in women: a questionnaire survey.

BACKGROUND: The mechanism of action of a contraceptive method is an importantg consideration in a woman's choice of contraception. For the development of new methods of contraception it is important to understand the acceptability of different contraceptive mechanisms within a population. METHODS: We recruited women attending contraceptive, termination of pregnancy or postnatal care services in Hong Kong for a questionnaire survey on their acceptability of the different ways in which contraceptive methods prevent pregnancy. Univariable and multivariable analyses were used to establish factors which may predict acceptability of the mechanism of action. RESULTS: A total of 1448 women completed the survey. The acceptability of contraceptive methods that act by preventing fertilisation ranked highest (78%), followed by those that inhibit ovulation (52%), disrupt implantation (43%) and dislodge an implanted embryo (30%). A history of termination of pregnancy was associated with greater acceptance of all posited contraceptive mechanisms. There was a very low degree of agreement between the declared acceptance of the various contraceptive mechanisms and the ever use of a method with the respective mechanism of action (Cohen's kappa coefficient range 0.017-0.162). CONCLUSIONS: In this population the acceptability of contraceptive methods that act by preventing fertilisation ranked highest, followed by those that inhibit ovulation, disrupt implantation and dislodge an implanted embryo. Women who had ever had a termination of pregnancy were more likely to accept all the posited contraceptive mechanisms.

Prevention of early onset group B streptococcal disease by universal antenatal culture-based screening in all public hospitals in Hong Kong.

OBJECTIVES: To determine the prevalence of maternal colonization with group B streptococcus (GBS), and early onset GBS disease (EOGBSD) after implementation of universal screening. METHODS: This was a three-year retrospective cohort study on universal antenatal rectovaginal culture-based screening and intrapartum antimicrobial prophylaxis (IAP) to colonized women in the public sector in Hong Kong. Routinely collected data including maternal colonization and EOGBSD were retrieved. RESULTS: Of 113,989 GBS screening performed, 21.8% were positive. The colonization rate was higher in the public hospitals (higher risk) than in the Maternal and Child Health Centers (lower risk) (23.7% vs 18.1%, p < .001), while their false negative rates were not greater than expected. Majority of eligible women opted for screening, and colonized women received IAP. There were 29 cases of EOGBSD with clinical signs and a positive blood or cerebrospinal fluid culture. Compared to clinical risk-based screening, EOGBSD incidence decreased after universal screening (1 vs 0.24 per 1000 births, p < .001). Although EOGBSD occurred at a higher rate in preterm than term infants, 86.7% occurred in the latter, and were associated with a false negative screening result (41.3%), lack of screening (20.7%) or unavailability of a colonization result at labour (13.8%). CONCLUSIONS: Maternal GBS colonization rate was higher than previously reported, and varied with different risk populations. EOGBSD reduced after universal screening.