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Showing papers by "Laura Fenster published in 1998"


Journal ArticleDOI
TL;DR: Computer algorithms were developed to derive menstrual segment length, ovulatory status, day of ovulation, and other parameters from the urine and diary data, and important associations included the following: age of > or = 35 years with decreased segment and follicular phase lengths; heavier weight with anovulation and increased follicle phase and decreased luteal phase lengths.
Abstract: A total of 403 healthy, premenopausal women, residing near Santa Clara, California, were recruited from a large health care plan in California for a study of menstrual function. After a telephone interview, participants collected daily urine samples and recorded bleeding and other information in diaries. Data were collected during 1990-1991. Urine samples were analyzed for creatinine and for estradiol and progesterone metabolites by enzyme-linked immunoassay. Computer algorithms were developed to derive menstrual segment length, ovulatory status, day of ovulation, and other parameters from the urine and diary data. (We use "segment" rather than "cycle" to avoid implying that normal cycling occurred.) The average length of participation was 141 (standard deviation, 45) days. The mean segment length was 28.8 (standard deviation, 4.4) days; follicular phase length, 16.0 (standard deviation, 4.4) days; and luteal phase length, 12.9 (standard deviation, 1.7) days; 19 (4.7%) women experienced anovulatory episodes. In exploratory multivariate analyses, important associations included the following: age of > or = 35 years with decreased segment and follicular phase lengths; heavier weight (upper quartile) with anovulation and increased follicular phase and decreased luteal phase lengths; Hispanic ethnicity with anovulation and increased segment length; and past difficulty in achieving pregnancy with anovulation and increased length and variability of segments and follicular phases. Urine biomarkers can be used successfully to evaluate menstrual function in epidemiologic studies.

138 citations


Journal ArticleDOI
TL;DR: This study confirms the association between cold tapwater and spontaneous abortion first seen in this county in 1980 and indicates that the agent(s) is not ubiquitous but is likely to have been present in Region I for some time.
Abstract: In 1992, we published four retrospective studies, conducted primarily within a single California county, which found higher spontaneous abortion rates among women who drank more tapwater than bottled water in early pregnancy. The current prospective study extends that investigation to other water systems. Pregnant women from three regions in California were interviewed during their first trimester. Multivariate analyses modeled the amount and type of water consumed at 8 weeks' gestation in each region in relation to spontaneous abortion rate. In Region I, which was within the previous study area, the adjusted odds ratio (OR) comparing high (> or = 6 glasses per day) consumption of cold tapwater with none was 2.17 [95% confidence interval (CI) = 1.22-3.87]. Furthermore, when women with high cold tapwater and no bottled water consumption were compared with those with high bottled water and no cold tapwater consumption, the adjusted odds ratio was 4.58 (95% CI = 1.97-10.64). Conversely, women with high bottled water consumption and no tapwater had a reduced rate of spontaneous abortion compared with those drinking tapwater and no bottled water (adjusted OR = 0.22; 95% CI = 0.09-0.51). Neither tap nor bottled water consumption altered the risk of spontaneous abortion in Regions II and III. Although controlling for age, prior spontaneous abortion, race, gestational age at interview, and weight somewhat strengthened the association in Region I, the distribution of these confounders did not vary appreciably across regions. This study confirms the association between cold tapwater and spontaneous abortion first seen in this county in 1980. If causal, the agent(s) is not ubiquitous but is likely to have been present in Region I for some time.

130 citations


Journal ArticleDOI
TL;DR: Findings suggest that the fecundity of men experiencing the stress of a family member's death might be temporarily diminished, and this should not be considered a cause for concern.

59 citations


Journal ArticleDOI
TL;DR: There was no evidence that an interaction between enzyme activity and caffeine intake during pregnancy resulted in risk of spontaneous abortion, and some association of the latter two caffeine-metabolizing enzymes with recurrent spontaneous abortion is suggested.
Abstract: In a case-control study of 73 women with and 141 women without spontaneous abortion, the authors determined the activity of the three principal caffeine-metabolizing enzymes--cytochrome P-4501A2 (CYP1A2), xanthine oxidase, and N-acetyltransferase 2--by measuring levels of caffeine metabolites in urine. After examining the effect of enzyme activity and different levels of caffeine intake, they concluded that there was no evidence that an interaction between enzyme activity and caffeine intake during pregnancy resulted in risk of spontaneous abortion. In a subsample comparing 24 cases with recurrent (two or more) spontaneous abortions and 21 controls with two or more livebirths and no previous spontaneous abortions, the unadjusted odds ratio for low CYP1A2 enzyme activity (below the median) was 0.92 (95% confidence interval (CI) 0.28-3.04) compared with higher CYP1A2 activity. The odds ratio for risk of recurrent spontaneous abortion and low xanthine oxidase activity (below the median) versus higher activity was 0.37 (95% CI 0.10-1.29). Phenotypically slow acetylators (N-acetyltransferase 2 index <0.37) had an odds ratio of 1.58 (95% CI 0.48-5.13) for recurrent loss compared with rapid acetylators. Thus, some association of the latter two caffeine-metabolizing enzymes with recurrent spontaneous abortion is suggested but may also be due to chance.

36 citations



Journal ArticleDOI
TL;DR: In this article, the authors proposed a method to solve the problem of the problem: image-based clustering and clustering, which is shown in Figure 1Figure 6Figure 7
Abstract: ImagesFigure 1Figure 6Figure 7

5 citations