Fertility patterns prior to testicular cancer diagnosis.

Although prenatal factors are associated with testicular cancer etiology, few studies have examined the reproductive profiles of men prior to diagnosis. This case--control study investigated fertility patterns prior to testicular cancer diagnosis by comparing pregnancies fathered by 201 men with testicular cancer and those fathered by 204 age- and neighborhood-matched controls. Regardless of histology, men with testicular cancer were less likely to have ever fathered a live-born infant (OR 0.

Allergy and infectious disease histories and the risk of childhood acute lymphoblastic leukaemia.

Infectious disease histories were evaluated in a population-based case-control study of childhood acute lymphoblastic leukaemia (ALL) as it has been hypothesised that delays in early infections are associated with an increased risk of disease. Allergy histories were also assessed as part of a broader evaluation of the role of immune factors in ALL. Cases (n = 255) were diagnosed between 1980 and 1991 at one of four referral centres in a 31-county area of New York State; controls (n = 760) were a random sample of live births from the same region, frequency matched to cases by sex, race and birth year.

Relative concentrations of organochlorines in adipose tissue and serum among reproductive age women.

Much of the available literature focusing on organochlorine exposure and human health effects has relied upon serum for quantifying exposure despite adipose tissue being the purported "gold standard". The accuracy of exposure status is dependent upon serum being a valid and reliable proxy for adipose tissue regardless of compound under study and served as the impetus for study. Serum and omentum fat concentrations for 62 polychlorinated biphenyls (PCBs) and 7 organochlorine pesticides (OCPs) were determined using gas chromatography with electron capture and compared to assess their relative abundance and correlation among 15 women aged 18-40 years undergoing laparoscopy.

Birth defects risk associated with maternal sport fish consumption: potential effect modification by sex of offspring.

Contaminated sport fish consumption may result in exposure to various reproductive and developmental toxicants, including pesticides and other suspected endocrine disruptors. We investigated the relation between maternal sport fish meals and risk of major birth defects among infants born to members of the New York State (NYS) Angler Cohort between 1986 and 1991 (n=2237 births). Birth defects (n=125 cases) were ascertained from both newborn medical records and the NYS Congenital Malformations Registry.

Are children born after assisted reproductive technology at increased risk for adverse health outcomes?

As assisted reproductive technologies (ARTs) are increasingly used to overcome infertility, there is concern about the health of the children conceived. The empirical evidence for associations with outcomes related to child health is variable and should be evaluated with consideration of methodological shortcomings. Currently, there is convincing evidence that ART treatment may increase the risk of a few outcomes.

Biomarkers for assessing reproductive development and health: Part 1--Pubertal development.

The proposed National Children's Study has helped raise awareness of the issues related to children's health and the importance of monitoring the growth and development of children from preconception through adulthood. Many genetic predispositions can adversely impact the normal development process, and various environmental exposures have been linked to adverse reproductive health in rodent models and a small number of accidental human exposures. To monitor reproductive health and identify adverse effects at the earliest possible juncture, investigators must develop a network of biomarkers covering all stages and aspects of reproductive development and function.

The value of home-based collection of biospecimens in reproductive epidemiology.

Detection, quantification, and prognosis of environmental exposures in humans has been vastly enhanced by the ability of epidemiologists to collect biospecimens for toxicologic or other laboratory evaluation. Ease of collection and level of invasiveness are commonly cited reasons why study participants fail to provide biospecimens for research purposes. The use of methodologies for the collection of biospecimens in the home offers promise for improving the validity of health effects linked to environmental exposures while maximizing the number and type of specimens capable of being collected in a timely and cost-effective manner.

Prospective pregnancy study designs for assessing reproductive and developmental toxicants.

The determinants of successful human reproduction and development may act as early as periconceptionally, underscoring the need to capture exposures during these critical windows when assessing potential toxicants. To identify such toxicants, couples must be studied longitudinally prior to conception without regard to a couple's ability to ascertain a clinically recognized pregnancy. We examined the utility and feasibility of prospective pregnancy study designs by conducting a systematic review of the literature to summarize relevant information regarding the planning, implementation, and success of previously published prospective pregnancy studies.

Our once-in-a-lifetime opportunity.

Longitudinal studies of the determinants of children's health are complex, costly, infrequent, and incredibly valuable. It has become clear in recent years that the periconceptional environment plays a surprisingly large role in the health of the resulting child. This short introduction to this mini-monograph briefly recaps the articles included herein and reminds us that adequate forethought and planning will result in a study that could shed new light on the earliest determinants of children's health and thereby fill critical data gaps.

Using commercial telephone directories to obtain a population-based sample for mail survey of women of reproductive age.

In the United States, sampling women of reproductive age from the general population for research purposes is a challenge. Even more difficult is conducting a population-based study of couples attempting pregnancy to assess fecundity and fertility or related impairments. To address the problem of obtaining representative samples from the population in order to study such health-related issues, a commercially and readily available CD-ROM telephone directory was used and tested as a sampling framework for studies aimed at enrolling gravid women aged 18-44 years.

Maternal fish consumption and infant birth size and gestation: New York State Angler Cohort Study.

Background: The scientific literature poses a perplexing dilemma for pregnant women with respect to the consumption of fish from natural bodies of water. On one hand, fish is a good source of protein, low in fat and a rich source of other nutrients all of which have presumably beneficial effects on developing embryos and fetuses. On the other hand, consumption of fish contaminated with environmental toxicants such as polychlorinated biphenyls (PCBs) has been associated with decrements in gestation and birth size.

Blood lead levels and sexual maturation in U.S. girls: the Third National Health and Nutrition Examination Survey, 1988-1994.

Using data from the Third National Health and Nutrition Examination Survey, we assessed measures of puberty in U.S. girls in relation to blood lead levels to determine whether sexual maturation may be affected by current environmental lead exposure.

Ethnic differences in the presence of secondary sex characteristics and menarche among US girls: the Third National Health and Nutrition Examination Survey, 1988-1994.

Objective: To assess measures of puberty-presence of pubic hair, breast development, and menarche-for 3 racial/ethnic groups of girls in the United States.

Methods: Using data from the Third National Health and Nutrition Examination Survey, this study sample was restricted to 1623 girls aged 8 to 16 years (466 non-Hispanic white, 589 non-Hispanic black, and 568 Mexican American) for whom information was available on Tanner stages of pubic hair and breast development. Subsequently, the sample was restricted to 1168 girls aged 10 to 16 years (330 non-Hispanic white, 419 non-Hispanic black, and 419 Mexican American) for whom menarche data were available.

PCB congeners and pesticides and female fecundity, New York State Angler Prospective Pregnancy Study.

Consumption of PCB-contaminated sport fish from Lake Ontario has been reported to be associated with diminished female fecundity. To identify Polychlorinated biphenyl (PCB) congeners and other pesticides that might be associated with reduced fecundity, we followed 102 women aged 20-34 years attempting pregnancy who completed daily diaries for 12 at risk menstrual cycles. Fecundity referred to time-to-pregnancy (TTP) or the number of at risk menstrual cycles required for pregnancy.

Methodologic considerations for population-based research on fetal deaths: overcoming data gaps.

Fetal deaths comprise a large component of perinatal mortality and remain an understudied pregnancy outcome, especially from a population perspective. Interpretation of the findings from clinical or community-based studies can be difficult without a clear understanding of fetal death at the population level. This article addresses the critical data gaps underlying population-based research on fetal deaths, including the magnitude and scope of the problem, the probability of occurrence, the populations at risk, and the importance of accounting for prior reproductive history.