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Christina C Lawson

Publications and source records attributed to Christina C Lawson.

7 recordsLinked to original sources
PubMed2006

Workgroup report: Implementing a national occupational reproductive research agenda--decade one and beyond.

The initial goal of occupational reproductive health research is to effectively study the many toxicants, physical agents, and biomechanical and psychosocial stressors that may constitute reproductive hazards in the workplace. Although the main objective of occupational reproductive researchers and clinicians is to prevent recognized adverse reproductive outcomes, research has expanded to include a broader spectrum of chronic health outcomes potentially affected by reproductive toxicants. To aid in achieving these goals, the National Institute for Occupational Safety and Health, along with its university, federal, industry, and labor colleagues, formed the National Occupational Research Agenda (NORA) in 1996. NORA resulted in 21 research teams, including the Reproductive Health Research Team (RHRT). In this report, we describe progress made in the last decade by the RHRT and by others in this field, including prioritizing reproductive toxicants for further study; facilitating collaboration among epidemiologists, biologists, and toxicologists; promoting quality exposure assessment in field studies and surveillance; and encouraging the design and conduct of priority occupational reproductive studies. We also describe new tools for screening reproductive toxicants and for analyzing mode of action. We recommend considering outcomes such as menopause and latent adverse effects for further study, as well as including exposures such as shift work and nanomaterials. We describe a broad domain of scholarship activities where a cohesive system of organized and aligned work activities integrates 10 years of team efforts and provides guidance for future research.

Drug-Related Side Effects and Adverse Reactions↗
PubMed2004

Changes in caffeine consumption as a signal of pregnancy.

OBJECTIVES: The purpose of this prospective study was to examine caffeine consumption and other signals of early pregnancy. STUDY DESIGN: One hundred and five pregnant, nonsmoking, coffee drinkers ages 18-40 were enrolled by the ninth week after their last menstrual period (LMP). Participants kept daily diaries of beverage and caffeine consumption and symptoms. Urine samples were collected to assess hormone metabolites. Descriptive statistics were generated. RESULTS: During the first trimester, 96% of subjects decreased or quit drinking coffee, 65% of whom reported a unique aversion to coffee. The mean daily caffeine consumption at LMP from coffee alone was 119 mg (S.D., 105), with a range 1-574 mg. There was a 59% decrease of mean daily consumption of caffeine from coffee between weeks 4 and 6, from 96 to 39 mg. The vast majority of subjects experienced nausea (98%) and appetite loss (93%); vomiting was less prevalent (54%). The most common dietary aversions included meat, coffee, spicy foods, and dairy products. Hormone metabolite patterns are reported. CONCLUSION: Signals of early pregnancy included an aversion to coffee in addition to nausea and vomiting, which resulted in decreased caffeine consumption. These symptoms often interfered with daily life and lasted beyond the first trimester for many. Consideration should be given that a decrease in caffeine consumption may be a signal for a healthy pregnancy and acting as a confounder.

Adolescent↗
PubMed2004

Paternal occupational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin and birth outcomes of offspring: birth weight, preterm delivery, and birth defects.

Agent Orange is a phenoxy herbicide that was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We studied pregnancy outcomes among wives of male chemical workers who were highly exposed to chemicals contaminated with TCDD and among wives of nonexposed neighborhood referents. For exposed pregnancies, we estimated serum TCDD concentration at the time of conception using a pharmacokinetic model. The mean TCDD concentration for workers' births was 254 pg/g lipid (range, 3-16,340 pg/g). The mean referent concentration of 6 pg/g was assigned to pregnancies fathered by workers before exposure. A total of 1,117 live singleton births of 217 referent wives and 176 worker wives were included. Only full-term births were included in the birth weight analysis (greater than or equal to 37 weeks of gestation). Mean birth weight among full-term babies was similar among referents' babies (n = 604), preexposure workers' babies (n = 221), and exposed workers' babies (n = 292) (3,420, 3,347, and 3,442 g, respectively). Neither continuous nor categorical TCDD concentration had an effect on birth weight for term infants after adjustment for infant sex, mother's education, parity, prenatal cigarette smoking, and gestation length. An analysis to estimate potential direct exposure of the wives during periods of workers' exposure yielded a nonstatistically significant increase in infant birth weight of 130 g in the highest exposure group (TCDD concentration > 254 pg/g) compared with referents (p = 0.09). Mothers' reports of preterm delivery showed a somewhat protective association with paternal TCDD (log) concentration (odds ratio = 0.8; 95% confidence interval, 0.6-1.1). We also include descriptive information on reported birth defects. Because the estimated TCDD concentrations in this population were much higher than in other studies, the results indicate that TCDD is unlikely to increase the risk of low birth weight or preterm delivery through a paternal mechanism. Key words: birth defects, birth weight, congenital anomalies, dioxin, occupation, paternal exposure, preterm birth, TCDD.

Adult↗
PubMed2003

An occupational reproductive research agenda for the third millennium.

There is a significant public health concern about the potential effects of occupational exposure to toxic substances on reproductive outcomes. Several toxicants with reported reproductive and developmental effects are still in regular commercial or therapeutic use and thus present potential exposure to workers. Examples of these include heavy metals, organic solvents, pesticides and herbicides, and sterilants, anesthetic gases, and anticancer drugs used in health care. Many other substances are suspected of producing reproductive or developmental toxicity but lack sufficient data. Progress has been limited in identifying hazards and quantifying their potencies and in separating the contribution of these hazards from other etiologic factors. Identifying the causative agents, mechanisms by which they act, and any potential target populations, present the opportunity to intervene and protect the reproductive health of workers. The pace of laboratory studies to identify hazards and to underpin the biologic plausibility of effects in humans has not matched the pace at which new chemicals are introduced into commerce. Though many research challenges exist today, recent technologic and methodologic advances have been made that allow researchers to overcome some of these obstacles. The objective of this article is to recommend future directions in occupational reproductive health research. By bridging interdisciplinary gaps, the scientific community can work together to improve health and reduce adverse outcomes.

Communication↗
PubMed2002

Pregnancy hormone metabolite patterns, pregnancy symptoms, and coffee consumption.

Because of contradictory reports of pregnancy outcomes and coffee intake, this study was designed to determine how hormone metabolite levels, symptoms, and coffee consumption patterns are related. Eligible subjects were recruited in Cincinnati, Ohio, from 1996 to 1998, aged 18-40 years, and nonsmokers; drank at least 18 ounces (1 ounce = 29.6 ml) of coffee per week (including decaffeinated) at the last menstrual period; and were enrolled by 9 weeks from the last menstrual period. Beverage consumption and pregnancy symptoms were recorded daily. Weekly, first-morning urine samples were collected to assess human chorionic gonadotropin, estrone-3-glucuronide, and pregnanediol-3-glucuronide. A time-dependent, repeated measures analysis was performed to test several associations. Data from 92 subjects were analyzed with the following results. 1) Coffee consumption was significantly, inversely associated with weekly levels of estrone-3-glucuronide and human chorionic gonadotropin. 2) Weekly hours of nausea were significantly, directly associated with human chorionic gonadotropin and inversely with estrone-3-glucuronide and pregnanediol-3-glucuronide. 3) Weekly coffee consumption was significantly associated with vomiting but not with nausea or appetite loss. 4) Weekly levels of pregnanediol-3-glucuronide were 32.2% lower in subjects who drank at least 8 ounces of coffee/day at the last menstrual period, though above what was necessary to maintain those pregnancies. This study shows the significance of these important variables to be considered in future research.

Adult↗