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M Joffe

Publications and source records attributed to M Joffe.

At least 37 records · Page 2Linked to original sources
PubMed2000

Time trends in biological fertility in Britain.

BACKGROUND: There is evidence of a decline in semen quality in some countries, including Britain, in recent decades. This retrospective cohort study examined the hypothesis that biological fertility had also declined. The trend in couple fertility was assessed by means of time to pregnancy (TTP--a sensitive and validated measure of fertility. METHODS: A representative sample of the British population aged 16-59 years was surveyed. TTP was obtained for all births conceived after unprotected intercourse that began during 1961-93, excluding contraceptive failures. The sample size was 1540. FINDINGS: In contrast to the original hypothesis, this study found that fertility has increased; the rising trend was accompanied by slight dips during 1976-80 and 1986-90. These results were consistent between male and female respondents, and undiminished by adjustment for possible confounding factors. A stronger and more consistent relation was found with the year when unprotected intercourse started (a period effect) than with the year of birth of either partner (a birth cohort effect). INTERPRETATION: The findings could not be explained by trends in age at first birth, increased treatment of subfertility, or changes in oral contraceptive use. If a decline in male fertility has occurred, it has been more than compensated for by a countervailing increase in couple fertility.

Adolescent↗
PubMed2000

Arterial hypertension and renal allograft survival.

CONTEXT: Several observational studies have investigated the significance of hypertension in renal allograft failure; however, these studies have been complicated by the lack of adjustment for baseline renal function, leaving the role of elevated blood pressure in allograft failure unclear. OBJECTIVE: To examine the relationship between blood pressure adjusted for renal function and survival after cadaveric allograft transplantation. DESIGN: Nonconcurrent historical cohort study conducted from 1985 through 1997. SETTING: University teaching hospital. PARTICIPANTS: A total of 277 patients aged 18 years or older who underwent cadaveric renal transplantation without another simultaneous organ transplantation and whose allograft was functioning for a minimum of 1 year. Follow-up continued through 1997 (mean follow-up, 5.7 years). MAIN OUTCOME MEASURE: Time to allograft failure (defined as death, return to dialysis, or retransplantation) by systolic, diastolic, and mean arterial blood pressure measurements at 1 year after transplantation. RESULTS: Multivariate Cox proportional hazards modeling demonstrated that nonwhite ethnicity, history of acute rejection, and nondiabetic kidney disease were significant predictors of failure (P = .01 for all). In addition, the calculated creatinine clearance at 1 year had an adjusted rate ratio (RR) for allograft failure per 10 mL/min (0.17 mL/s) of 0.74 (95% confidence interval [CI], 0.62-0.88). The RR per 10-mm Hg increase in blood pressure measured at 1 year after transplantation, after adjustment for creatinine clearance, was 1.15 (95% CI, 1.02-1.30) for systolic pressure, 1.27 (95% CI, 1.01-1.60) for diastolic pressure, and 1.30 (95% CI, 1.05-1.61) for mean arterial pressure. Supplemental analyses that did not include death as a failure event or reduce the minimum allograft survival time for study subjects to 6 months yielded results consistent with the primary analysis. There was no evidence of modification of the blood pressure-allograft failure relationship by ethnicity or diabetes mellitus. CONCLUSIONS: Systolic, diastolic, and mean arterial blood pressures at 1 year posttransplantation strongly predict allograft survival adjusted for baseline renal function. More aggressive control of blood pressure may prolong cadaveric allograft survival.

Adult↗
PubMed2000

Do parental factors affect male and female fertility?

There is little published evidence on parental characteristics and the fertility of their offspring of either sex. Maternal smoking has been reported to reduce fertility in both sexes and was also suggested to be relevant to the health of the male reproductive system on the basis of descriptive epidemiology. We undertook a cohort study based on a sample representative of the British population born in 1958 who have been followed up since birth. The outcome variable was time to pregnancy measured in months, up to age 33 years. Antecedent variables were the age of both parents; maternal smoking, height, prepregnancy body mass index, and parity; and paternal social class (manual/nonmanual labor). First births to cohort members were analyzed using a Cox logistic model for discrete "survival" times. A total of 1,714 and 2,587 values of time to pregnancy were available, respectively, for male and female cohort members. In the unadjusted analyses, all odds ratios were in the range 0.9-1.1, apart from the father's social class. In the adjusted analyses, this effect also disappeared. We conclude that the observed heterogeneity in biological fertility is unrelated to those characteristics of parents that we were able to analyze.

Adult↗
PubMed2000

Forensic evidence findings in prepubertal victims of sexual assault.

OBJECTIVE: The American Academy of Pediatrics recommends forensic evidence collection when sexual abuse has occurred within 72 hours, or when there is bleeding or acute injury. It is not known whether these recommendations are appropriate for prepubertal children, because few data exist regarding the utility of forensic evidence collection in cases of child sexual assault. This study describes the epidemiology of forensic evidence findings in prepubertal victims of sexual assault. METHODS: The medical records of 273 children <10 years old who were evaluated in hospital emergency departments in Philadelphia, Pennsylvania, and had forensic evidence processed by the Philadelphia Police Criminalistics Laboratory were retrospectively reviewed for history, physical examination findings, forensic evidence collection, and forensic results. RESULTS: Some form of forensic evidence was identified in 24.9% of children, all of whom were examined within 44 hours of their assault. Over 90% of children with positive forensic evidence findings were seen within 24 hours of their assault. The majority of forensic evidence (64%) was found on clothing and linens, yet only 35% of children had clothing collected for analysis. After 24 hours, all evidence, with the exception of 1 pubic hair, was recovered from clothing or linens. No swabs taken from the child's body were positive for blood after 13 hours or sperm/semen after 9 hours. A minority of children (23%) had genital injuries. Genital injury and a history of ejaculation provided by the child were associated with an increased likelihood of identifying forensic evidence, but several children had forensic evidence found that was unanticipated by the child's history. CONCLUSIONS: The general guidelines for forensic evidence collection in cases of acute sexual assault are not well-suited for prepubertal victims. The decision to collect evidence is best made by the timing of the examination. Swabbing the child's body for evidence is unnecessary after 24 hours. Clothing and linens yield the majority of evidence and should be pursued vigorously for analysis.

Child↗
PubMed2000

Time to pregnancy among male workers of the reinforced plastics industry in Denmark, Italy and The Netherlands. ASCLEPIOS.

OBJECTIVES: The relationship between occupational styrene exposure and male fecundity was examined. METHODS: Among 1560 Danish, Italian, and Dutch reinforced plastics workers, 220 styrene-exposed workers and 382 unexposed referents who had fathered a child were identified. A total of 768 historical styrene measurements conducted in 1970-1996 in the study companies formed the basis for semiquantitative exposure assessment in combination with measurements of urinary styrene metabolite levels. All the subjects were interviewed about work conditions and other factors potentially related to reduced fecundity. Fecundity was measured as the reported time to pregnancy (number of months a couple needed to conceive their youngest child). RESULTS: A statistically nonsignificantly reduced fecundity was observed for the styrene-exposed workers [fecundity ratio 0.79, 95% confidence interval (95% CI) 0.59-1.05]. But no consistent pattern of a detrimental effect on fecundity was found when time to pregnancy was related to worktasks indicating higher styrene exposure levels or semiquantitative or quantitative measures of styrene exposure. The workers with high exposure showed a fecundity ratio of 1.09 (95% CI 0.69-1.72). CONCLUSIONS: It is unlikely that styrene exposure has a strong effect on male fecundity.

Adult↗
PubMed1999

[Pesticides and time to pregnancy among Danish farmers].

The aim of this study was to examine time to pregnancy among farmers who used pesticides (traditional farmers) and farmers who did not (organic farmers). A total of 904 men, selected from the Danish Ministry of Agriculture lists of traditional and organic farmers, participated in telephone interviews. The participation rate was 84%. Information was collected on "time to pregnancy" for the youngest child, exposure to pesticides and potential confounders. Using the discrete analogue of the Cox Regression Model (including potential confounders: male and female smoking, female age, parity and contraceptive method), the fecundability ratio between traditional farmers using pesticides and organic farmers was 1.03 (95% CI: 0.75-1.40). In the group of farmers who sprayed with pesticides, none of the characteristics related to the use of pesticides could account for the variation in time to pregnancy. No overall effect of pesticides on male fecundability could be demonstrated in this retrospective study among Danish farmers.

Adult↗
PubMed1999

Effects of pesticide exposure on time to pregnancy: results of a multicenter study in France and Denmark. ASCLEPIOS Study Group.

The aim of this study was to determine whether there was a relation between male exposure to pesticides and the amount of time needed to conceive (time to pregnancy) for farmers and agricultural workers in France and Denmark. The authors used retrospective studies to compare the time to pregnancy of couples in which the man was exposed to pesticides during the year before the birth of their youngest child with that of couples in which the man was not exposed. In 1995 and 1996, the authors studied 362 French rural workers (142 exposed to pesticides and 220 not exposed), 449 Danish farmers (326 conventional farmers exposed to pesticides and 123 nonexposed organic farmers), and 121 Danish greenhouse workers exposed to pesticides. The fecundability ratio for exposure to pesticides (Cox model, before and after adjustment for confounding factors) did not differ from 1 in any of the three populations. In France, the adjusted fecundability ratio was 1.17 (95% confidence interval (CI) 0.89-1.55) for exposed and nonexposed agricultural workers. In Denmark, it was 1.09 (95% CI 0.82-1.43) for exposed and nonexposed farmers and 0.83 (95% CI 0.69-1.18) for greenhouse workers and nonexposed farmers. Thus, this study found no relation between fertility (time to pregnancy) and male exposure to pesticides.

Adult↗
PubMed1999

Objectives, designs and populations of the European Asclepios study on occupational hazards to male reproductive capability.

The main objective of the Asclepios program was to examine occupational risk factors for the male reproductive system. The program focused on occupational exposure to fungicides (farmers, greenhouse workers, and vineyard workers), styrene (laminators in the reinforced plastics industry) and inorganic lead (battery workers, foundry workers, and lead smelters). Questionnaire studies of time to pregnancy were combined with longitudinal and cross-sectional studies of semen quality. The 8 data-collecting centers addressed 6553 male workers and contributed time-to-pregnancy values on the 3077 most recent pregnancies. Data collection was by interview or self-collection. The average response rate across all exposures and centers was 69.8%. The Asclepios project is the first international multicenter research project on environmental risks to male reproductive function. A protocol for epidemiologic research on occupational risk factors to the male reproductive system was developed, and links between epidemiologic and experimental units were established. The majority, but not all, of the studies was completed within the given time frame.

Adult↗
PubMed1998

Time to pregnancy and exposure to pesticides in Danish farmers. ASCLEPIOS Study Group.

OBJECTIVE: Circumstantial evidence suggests that organic farmers may have higher sperm count than other men, but comprehensive epidemiological studies of male fecundity among farmers have never been carried out. A substantial increase of sperm count is expected to translate into a shorter time to pregnancy--the number of menstrual cycles or months it takes a couple to get pregnant from discontinuation of birth control. Toxicological effects on spermatogenesis in humans and animals have been described after exposure to several pesticides. The aim of this study was to examine time to pregnancy among farmers who used pesticides (traditional farmers) and farmers who did not (organic farmers). METHODS: A total of 904 (84%) men, selected from the Danish Ministry of Agriculture lists of traditional and organic farmers, participated in telephone interviews. Information was collected on time to pregnancy for the youngest child, exposure to pesticides, and potential confounders. RESULTS: With the discrete analogue of the Cox regression model (including potential confounders: male and female smoking, female age, parity, and contraceptive method), the fecundability ratio between traditional farmers who used pesticides and organic farmers was 1.03 (95% confidence interval (95% CI) 0.75 to 1.40). In the group of farmers who sprayed with pesticides, none of the characteristics related to the use of pesticides could account for the variation in time to pregnancy. CONCLUSIONS: No overall effect of pesticides on male fecundability was found in this retrospective study among Danish farmers. Also, we found no evidence of higher male fecundability in organic farmers.

Adolescent↗
PubMed1998

Polymerase chain reaction detection of Haemophilus ducreyi DNA.

OBJECTIVES: To develop a polymerase chain reaction (PCR) method to detect Haemophilus ducreyi DNA in cultured isolates and clinical material. METHODS: Primers specific to the H ducreyi 16s rRNA gene were synthesised. PCR conditions were optimised and products were verified by restriction endonuclease digestion and agarose gel electrophoresis. RESULTS: The method was able to detect all 28 H ducreyi strains tested; specificity was demonstrated using lysates of 12 related organisms. Applied to clinical samples from genital ulcer swabs obtained in Harare, Zimbabwe, H ducreyi DNA was detected in repeated assays in 35 clinical samples. CONCLUSION: PCR amplification using primers from the 16s rRNA gene may be a useful alternative to culture for the detection of H ducreyi and the diagnosis of chancroid.

Chancroid↗
PubMed1998

Trends and international comparisons in infertility in circumpolar areas.

Infertility is an increasing problem for both individuals and societies. The number of couples seeking treatment for infertility is increasing each year, and public interest seems to be rising along with the new treatment methods and the improving results. Male infertility is also of great interest now that several studies suggest a deterioration in the quality of semen in many countries, Finland being an exception. The assisted reproductive technologies have improved tremendously since the first child conceived by in vitro fertilization was born in 1978. The new techniques include e.g. intrauterine insemination (IUI), gamete intrafallopian transfer (GIFT), in vitro fertilization (IVF), intracellular sperm injection (ICSI) and various combination treatments. These treatments are costly and both physically and emotionally stressful, and the success rate varies according to the aetiology of infertility, the age of the woman treated and the method used. More information is needed about the aetiology and incidence of fertility disorders as well as about the availability of treatment in the circumpolar areas and the couples' opinions of treatment. Our own study population, which was drawn form the northern Finland birth cohort for 1966, provides an outstanding opportunity to study these issues, since data are available for the whole life course of the individuals, dating back to prenatal life.

Adult↗
PubMed1997

Postmenopausal hormone therapy and mortality.

BACKGROUND: Postmenopausal hormone therapy has both benefits and hazards, including decreased risks of osteoporosis and cardiovascular disease and an increased risk of breast cancer. METHODS: We examined the relation between the use of postmenopausal hormones and mortality among participants in the Nurses' Health Study, who were 30 to 55 years of age at base line in 1976. Data were collected by biennial questionnaires beginning in 1976 and continuing through 1992. We documented 3637 deaths from 1976 to 1994. Each participant who died was matched with 10 controls alive at the time of her death. For each death, we defined the subject's hormone status according to the last biennial questionnaire before her death or before the diagnosis of the fatal disease; this reduced bias caused by the discontinuation of hormone use between the time of diagnosis of a potentially fatal disease and death. RESULTS: After adjustment for confounding variables, current hormone users had a lower risk of death (relative risk, 0.63; 95 percent confidence interval, 0.56 to 0.70) than subjects who had never taken hormones; however, the apparent benefit decreased with long-term use (relative risk, 0.80; 0.67 to 0.96, after 10 or more years) because of an increase in mortality from breast cancer among long-term hormone users. Current hormone users with coronary risk factors (69 percent of the women) had the largest reduction in mortality (relative risk, 0.51; 95 percent confidence interval, 0.45 to 0.57), with substantially less benefit for those at low risk (13 percent of the women; relative risk, 0.89; 95 percent confidence interval, 0.62 to 1.28). CONCLUSIONS: On average, mortality among women who use postmenopausal hormones is lower than among nonusers; however, the survival benefit diminishes with longer duration of use and is lower for women at low risk for coronary disease.

Adult↗
PubMed1997

Time to pregnancy: a measure of reproductive function in either sex. Asclepios Project.

INTRODUCTION: Growing evidence of reproductive effects associated with occupational and environmental agents has created the need for research with sensitive and well validated methods. There is a complex relation between manifest effects and underlying pathogenic processes. Conceptions will on average tend to be delayed in a population exposed to an agent that causes embryonic damage, an increase in germ cell mutations, or decreased fertility. STUDYING TIME TO PREGNANCY: Time to pregnancy can be used to measure the degree of delay in conceiving, across the whole continuum of biological fertility, in either men or women. The distribution of time to pregnancy largely reflects a sorting process, as the more fertile couples become progressively less well represented with the passage of time. The basic research strategy is comparison of the time to pregnancy within groups defined by their exposures, allowing for potential confounding factors relating not only to the study subject but also to his or her partner. MEASUREMENT AND VALIDITY: Prospective and retrospective methods are available, and each has strengths and weaknesses. Prospective studies have some theoretical advantages, but have unrepresentative populations and problems of feasibility and cost. Retrospective assessment of time to pregnancy is feasible with a short questionnaire, without intruding into sensitive areas of respondents' lives, with good validity at the group level, and without the necessity of large populations. Potential biases have been identified that can be minimised by careful design and analysis; the principal remaining problem is difficulty in obtaining exposure data retrospectively.

Bias↗