Fluoride content of tank water in Australia.

BACKGROUND: The aims of this study were to: (1) analyse the fluoride content of tank water; (2) determine whether the method of water collection or storage influenced fluoride content; and (3) survey participant attitudes towards water fluoridation. METHODS: Plastic tubes and a questionnaire were distributed through dentists to households with water tanks in Victoria. A midstream tank water sample was collected and fluoride analysed in triplicate using ion chromatography RESULTS: All samples (n = 123) contained negligible amounts of fluoride, with a mean fluoride concentration of <0.01 ppm (range: <0.01-0.18 ppm). No statistically significant association was found between fluoride content and variables investigated such as tank material, tank age, roof material and gutter material. Most people did not know whether their tank water contained fluoride and 40.8% preferred to have access to fluoridated water. The majority thought fluoride was safe and more than half of the respondents supported fluoridation. Fluoride content of tank water was well below the optimal levels for caries prevention. CONCLUSIONS: People who rely solely on tank water for drinking may require additional exposure to fluoride for optimal caries prevention.

The return of fertility after discontinuation of oral contraception in Malaysian women.

The return of fertility after discontinuation of oral contraception was studied in a cross-sectional survey of 61 patients who were desirous of a further pregnancy. For controls, 380 women who did not take any oral contraception were used. Cumulative conception rates in the pill users were reduced but not significantly during the first three (p = 0.15) and six months (p = 0.20). By 12 months this difference was negligible (p = 0.28). We conclude that there is no significant delay in return of fertility following cessation of oral contraception in our group of Malaysian women.

PIP: A case control study was conducted among all pregnant women attending the prenatal clinic at the University Hospital in Kuala Lumpur, Malaysia, during May-October 1989 to determine the return of fertility after discontinuation of the combined oral contraceptive (OC). There were 61 women who had used OCs for at least 6 months before the current pregnancy. The remaining 380 women had not used any contraception at all before the current pregnancy. The former OC users were less likely to have conceived at 3 and 6 months than the controls (56% vs. 66%, and 70% vs. 78%, respectively). Neither difference in conception rates was significant, however (p = 0.15 and 0.20, respectively). At 12 months, the conception rates were 90% for cases and 94% for controls (p = 0.28). At 10 months, among former OC users, nulliparous women were more likely to have conceived than parous women (100% vs. 80%). In fact, at 1 year, 14% of the parous women still had not conceived. These findings show that OC use does not significantly delay return of fertility in this group of Malaysian women.