Outdoor carbon monoxide, nitrogen dioxide, and sudden infant death syndrome.

AIMS: To investigate whether infants who died of SIDS were more likely to have higher acute and lifetime average exposures to outdoor carbon monoxide (CO) and nitrogen dioxide (NO2) than comparison healthy infants. METHODS: A total of 169 case and 169 matched control infants born between 1988 and 1992, were studied. CO and NO2 concentrations, averaged for all days within the infant's lifespan, and the last 30 days, 7 days, 3 days, and 1 day of life were obtained from air pollutant data provided by the California Air Resources Board. RESULTS: Based on monthly aggregated data, average CO and particularly NO2 were associated with SIDS count, even after adjustment for seasonal trends. SIDS outcome was not significantly associated with high average outdoor CO levels for any time period. However, high average outdoor NO2 levels on the last day of the infant's exposure period were significantly associated with SIDS; the adjusted odds ratio was 2.34 (95% CI 1.13 to 4.87). CONCLUSIONS: SIDS may be related to high levels of acute outdoor NO2 exposure during the last day of life. Further studies are needed to replicate this finding.

Female and male lifestyle habits and IVF: what is known and unknown.

There is no greater tribute to the importance and efficacy of IVF than the fact that >1 x 10(6) babies have been born to infertile couples since its clinical introduction in 1978. Despite enormous advances regarding the technical aspects of the IVF procedure, the parents' contribution has virtually been ignored when considering aspects that influence success rates. This systematic review focuses on the effects of female and male lifestyle habits (specifically: smoking, alcohol and caffeine use, and psychological stress) on the reproductive endpoints of IVF (i.e. oocyte aspiration, fertilization, embryo transfer, achievement of a pregnancy, live birth delivery, and perinatal outcomes, e.g. low birthweight, multiple gestations). What is currently known in the field of lifestyle habits and IVF? There is compelling evidence that smoking has a negative influence on IVF outcomes, whereas for stress, the evidence is suggestive but insufficient due to the heterogeneity of studies. The evidence for the effects of alcohol and caffeine on IVF is inadequate, and therefore unknown, due to the scarcity of studies.

A prospective study of the effects of female and male caffeine consumption on the reproductive endpoints of IVF and gamete intra-Fallopian transfer.

BACKGROUND: This study evaluated the timing and amount of caffeine intake by women and men undergoing IVF and gamete intra-Fallopian transfer (GIFT) on oocyte retrieval, sperm parameters, fertilization, multiple gestations, miscarriage, and live births. METHODS: A prospective study of 221 couples was conducted in Southern California between 1993 and 1998. "Usual" caffeine intake during lifetime and 1 year prior to attempt, caffeine intake during the week of the initial clinic visit, as well as intake during the week of the procedure, was evaluated from beverages (coffee, soda, tea) and chocolates. RESULTS: Not achieving a live birth was significantly associated with "usual" female caffeine consumption [adjusted odds ratios (95% confidence intervals): 3.1 (1.1, 9.7) and 3.9 (1.3, 11.6) for intake of >2-50 and 50 mg/day, compared with 0-2 mg/day] and consumption during the week of the initial visit [2.9 (1.1, 7.5) and 3.8 (1.4, 10.7)] female compared with 0-2 mg/day, although caffeine use was low. Infant gestational age decreased by 3.8 (-6.9, -0.7) or 3.5 (-6.7, -0.3) weeks for women who consumed >50 mg/day of caffeine "usually" or during the week of the initial visit. The odds of having multiple gestations increased by 2.2 (1.1, 4.4) and 3.0 (1.2, 7.4) for men who increased their "usual" intake or intake during the week of the initial visit by an extra 100 mg/day. Caffeine intake was not significantly associated with other outcomes. CONCLUSIONS: This is the first IVF/GIFT study to report any effect of caffeine on live births, gestational age, and multiple gestations. If these findings are replicated, caffeine use should be minimized prior to and while undergoing IVF/GIFT.

A prospective study of stress among women undergoing in vitro fertilization or gamete intrafallopian transfer.

OBJECTIVE: To evaluate whether baseline or procedural stress during in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT) affects pregnancy or live birth delivery rates. DESIGN: Prospective study. SETTING: Seven clinics in Southern California between 1993 and 1998. PATIENT(S): One hundred and fifty-one women completed two questionnaires. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The number of oocytes aspirated and fertilized, the number of embryos transferred, the achievement of a pregnancy, live birth delivery, and infant outcomes. RESULT(S): Positive-affect negative-affect score at baseline negatively influenced the number of oocytes retrieved and embryos transferred. A higher expectation of pregnancy was associated with greater numbers of oocytes fertilized and embryos transferred. At baseline, the risk of no live birth was 93% lower for women who had the highest positive-affect score compared to those with the lowest score. Furthermore, the score on the Infertility Reaction Scale was related to negative outcomes in live birth delivery, infant birth weight, and multiple births. During the time of the procedure, the PANAS and Bipolar Profile of Moods States results were related to the number of oocytes fertilized and embryos transferred; stress did not affect pregnancy or delivery. CONCLUSION(S): Baseline (acute and chronic) stress affected biologic end points (i.e., number of oocytes retrieved and fertilized), as well as pregnancy, live birth delivery, birth weight, and multiple gestations, whereas (procedural) stress only influenced biologic end points.

Maternal and paternal recreational drug use and sudden infant death syndrome.

OBJECTIVE: To determine whether maternal or paternal use of cocaine, opiates, or marijuana during conception and pregnancy and postnatally increases the risk of sudden infant death syndrome (SIDS) during the first year of the infant's life. This is an important issue and may prove useful in further decreasing the rate of SIDS. METHODS: A case-control study was conducted consisting of 239 infants who died of SIDS in southern California between 1989 and 1992, and 239 healthy infants who were matched on the basis of birth hospital, date of birth, age, and sex. Specific drug use at the period of conception, during pregnancy and breastfeeding, and in the presence or vicinity of the infant was ascertained by telephone for the white, African American, Hispanic, Asian American, and Pacific Islander case and control fathers and mothers. RESULTS: Maternal recreational drug use during pregnancy was not associated with the risk of SIDS after adjusting for maternal smoking during pregnancy (adjusted odds ratio [OR] = 2.0; 95% confidence interval [CI], 0.6-6.5). There were statistically significant differences between case and control fathers' use of marijuana during conception (OR = 2.2; 95% CI, 1.2-4.2; P =.01), during pregnancy (OR = 2.0; 95% CI, 1.0-4.1; P =.05), and postnatally (OR = 2.8; 95% CI, 1.1-7.3; P =.04) and the risk of SIDS, while adjusting for paternal smoking and alcohol use. CONCLUSIONS: There was no association between maternal recreational drug use and SIDS. Paternal marijuana use during the periods of conception and pregnancy and postnatally were significantly associated with SIDS. The role of paternal psychoactive drug use, especially the relationship between marijuana and SIDS, is an understudied area; however, before any definitive role for the father can be confirmed, these findings should be investigated and replicated in future studies.

Effects of female and male smoking on success rates of IVF and gamete intra-Fallopian transfer.

BACKGROUND: Smoking by both male and female partners may play a significant role in the success rates of assisted reproductive technologies. The objective of this 5-year prospective study was to investigate the influence of cigarette smoking by the wife, husband, and couple at various time points (e.g. lifetime, week prior, or during the procedures) on different biological parameters of IVF and gamete intra-Fallopian transfer (GIFT). METHODS AND RESULTS: A total of 221 couples, aged >20 years, of Caucasian, Black, Asian or Hispanic descent were recruited from seven infertility clinics located in Southern California. Couples (i.e. either female or male or both) who ever smoked compared with non-smokers, had adjusted relative risks (RR) of 2.41 (95% CI 1.07-5.45, P = 0.03) of not achieving a pregnancy, and 3.76 (95% CI 1.40-10.03, P < 0.01) of not having a live birth delivery, while adjusting for potential confounders. For couples who smoked for >5 years, there was an adjusted RR = 4.27 of not achieving a pregnancy (95% CI l.53-11.97, P = 0.01). The number of oocytes retrieved decreased by 40% for couples (smokers, n = 6) and by 46% for men who smoked during the week of the visit for IVF or GIFT. Women who smoked in their lifetime had adjusted risks of 2.71 of not achieving a pregnancy (95% CI 1.37-5.35, P < 0.01), and 2.51 (95% CI 1.11-5.67, P < 0.03) of not having a live birth delivery. CONCLUSIONS: There is compelling evidence that couples should be made aware that smoking years before undergoing IVF and GIFT can impact treatment outcome. This study may also provide insight into the timing and effects of male and female smoking on natural reproduction.

Breast cancer histology in Caucasians, African Americans, Hispanics, Asians, and Pacific Islanders.

STUDY OBJECTIVES: To investigate the association between race/ethnicity and histologic types of breast cancer. DESIGN: Cross-sectional study. SETTING: Population-based data from the Northern California Tumor Registry, which is part of the National Cancer Institute's Surveillance, Epidemiology and End Results Program. PARTICIPANTS: A total of 2759 breast cancer cases diagnosed in 1988. MAIN RESULTS: Tumors were classified as ductal, lobular, and mixed/unspecified carcinoma. Ductal carcinoma was the most common (83.6%) and lobular carcinoma was the rarest. Most cases were diagnosed in the localized stage (56.3%). Caucasian women had the highest rates of total breast cancer (240.9/100,000), ductal and lobular. In African-American women, the odds of ductal carcinoma were twice that of lobular carcinoma, compared with Caucasian women (odds ratio [OR] = 2.0, 95% confidence interval [CI] 1.0-3.9) after adjusting for age, site, and stage at diagnosis. Similarly, Asian and Hispanic women also had higher, non-statistically significant odds of ductal versus lobular carcinoma compared with Caucasians (OR = 1.8 [95% CI 0.9-3.7] and 1.6 [95% CI 0.8-3.4], respectively). CONCLUSIONS: Future studies should investigate how racial/ethnic differences in histology among breast cancer patients will influence life expectancy, against a backdrop of health care access, sociocultural issues, lifestyle habits, reproductive history, family history, and tumor characteristics.

Tracking strategies involving fourteen sources for locating a transient study sample: parents of sudden infant death syndrome infants and control infants.

Strategies involving 14 sources were used to locate 230 parents of sudden infant death syndrome infants who died in Southern California between 1989 and 1992 and 255 parents of healthy, living infants matched by birth hospital, birth date, race and sex. The sample consisted of adults of reproductive age residing in Southern California. After an event of sudden infant death, many parents moved without a forwarding address; only their names, last known address, and the infant's race, birth date, and sex were available. There was no access to birth certificates, obstetric or pediatric medical records, parents' Social Security numbers, or parents' birth dates. The most successful tracking sources for case parents were the Department of Motor Vehicles, postal service, reverse directory and neighbors, private investigator, and California Medicaid services. For control parents, the post office, Department of Motor Vehicles, and Folks Finders proved the most helpful. Using a combination of the 14 sources achieved an adequate sample size.

Job stress and preeclampsia.

We conducted a case-control study to determine whether job strain (or stress) during pregnancy resulted in an increased risk of preeclampsia. We compared 110 nulliparous Caucasian and African-American women who had preeclampsia with 115 healthy nulliparous controls. All subjects gave birth between 1984 and 1987 in Chapel Hill, NC. Occupation was ascertained during a telephone interview. We assigned each job title a strain (or stress) score in accordance with the occupational database developed by Karasek. Overall, 54 (49%) of the control women worked during pregnancy, 14 in high-stress jobs. Logistic regression analysis indicated a 3.1-fold [95% confidence interval (CI) = 1.2-7.8] increased risk of preeclampsia for women employed in high-stress jobs (high psychological demand, low decision latitude) and an odds ratio of 2.0 (95% CI = 1.0-4.3) for low-stress jobs compared with nonworking women, while simultaneously adjusting for age, race, family history of preeclampsia, history of hypertension in the subject's mother, gravidity, smoking during pregnancy, timing of the first prenatal visit, and type of birth control used by the couple before the pregnancy. Furthermore, working women had 2.3 times the risk of developing preeclampsia (95% CI = 1.2-4.6) compared with nonworking women. Work-related psychosocial strain increased the risk of preeclampsia in our study.

Bed sharing and the sudden infant death syndrome.

OBJECTIVE: To determine whether infants who died of the sudden infant death syndrome routinely shared their parents' bed more commonly than control infants. DESIGN: Case-control study. SETTING: Southern California. SUBJECTS: 200 white, African-American, Latin American, and Asian infants who died and 200 living controls, matched by birth hospital, date of birth, sex, and race. MAIN OUTCOME MEASURES: Routine bedding (for example, crib, cradle), day and night time sleeping arrangement (for example, alone or sharing a bed); for cases only, sleeping arrangement at death. Differences in bed sharing practices among races. RESULTS: Of the infants who died of the syndrome, 45 (22.4%) were sharing a bed. Daytime bed sharing was more common in African-American (P < 0.001) and Latin American families (P < 0.001) than in white families. The overall adjusted odds ratio for the syndrome and routine bed sharing in the daytime was 1.38 (95% confidence interval 0.59 to 3.22) and for night was 1.21 (0.59 to 2.48). These odds ratios were adjusted for routine sleep position, passive smoking, breast feeding, intercom use, infant birth weight, medical conditions at birth, and maternal age and education. There was no interaction between bed sharing and passive smoking or alcohol use by either parent. CONCLUSIONS: Although there was a significant difference between bed sharing among African-American and Latin American parents compared with white parents, there was no significant relation between routine bed sharing and the sudden infant death syndrome.

A case-control study of routine and death scene sleep position and sudden infant death syndrome in Southern California.

OBJECTIVE: To investigate whether infants who died of sudden infant death syndrome (SIDS) were routinely placed in different sleep positions compared with healthy infants in a multiethnic diverse population in the United States. DESIGN: A population-based case-control study. SETTING: Five counties in Southern California including Los Angeles, Orange, San Bernardino, Riverside, and San Diego. PARTICIPANTS: Parents of 200 white, African-American, Hispanic, and Asian infants who died of SIDS between January 1989 and December 1992 and parents of 200 healthy, living infants matched on the basis of birth hospital, birth date, race, and gender. Information was obtained from detailed telephone interviews with the parents and validated with obstetric and pediatric records. MAIN OUTCOME MEASURES: Routine sleep position, type of bedding, and objects in bed were determined for both case and control infants, while the last-placed and found sleep and face positions at death were reported for SIDS infants. RESULTS: Approximately 66% of SIDS infants and 64% of comparison infants routinely slept on their abdomens (P = .91). At the time of death, 80% of cases were found sleeping on their abdomens. There was no difference in routine sleep position for SIDS infants and comparison infants (odds ratio = 0.76; 95% confidence interval, 0.42 to 1.38), while simultaneously adjusting for birth weight (in grams), medical conditions at birth, breast-feeding, passive smoking, maternal recreational drug use, prenatal care, and infant vomiting. Hispanic parents routinely placed their infants on their abdomens less frequently than white parents (P < .01). However, the prone sleep position (face down) was the most commonly found sleep position at death in both Hispanic and non-Hispanic infants. CONCLUSIONS: Routine prone sleep position was not associated with an increased risk of SIDS in this study population. The results need to be confirmed with other parents of SIDS infants interviewed before the height of publicity regarding prone sleep position in the United States.

The effect of passive smoking and tobacco exposure through breast milk on sudden infant death syndrome.

OBJECTIVE: To examine the relationship between sudden infant death syndrome (SIDS) and smoking during pregnancy; postnatal tobacco smoke exposure from the mother, father, live-in-adults, and day care providers; and postnatal smoke exposure from breast-feeding. DESIGN: Case-control study. SETTING: Five counties in Southern California. PARTICIPANTS: A total of 200 white, African-American, Hispanic, and Asian parents of infants who died of SIDS between 1989 and 1992 were compared with 200 control parents who delivered healthy infants. Case infants were matched to control infants on the basis of birth hospital, birth date, gender, and race. All information was obtained from a detailed telephone interview and validated with medical records. MAIN OUTCOME MEASURES: Risk of SIDS associated with passive smoking by the mother, father, live-in adults, and day care providers; smoking in the same room as the infant; total number of cigarettes smoked by all adults; and maternal smoking during the time period of breast-feeding. RESULTS: Conditional logistic regression resulted in overall adjusted odds ratios (ORs) for SIDS associated with passive smoke from the mother of 2.28, the father of 3.46, other live-in adults of 2.18, and all sources of 3.50 (95% confidence interval, 1.81 to 6.75), while simultaneously adjusting for birth weight, sleep position, prenatal care, medical conditions at birth, breast-feeding, and maternal smoking during pregnancy. A dose-response effect was noted for SIDS associated with increasing numbers of cigarettes, as well as total number of smokers. Breast-feeding was protective for SIDS among nonsmokers (OR = 0.37) but not smokers (OR = 1.38), when adjusting for potential confounders. CONCLUSIONS: Passive smoking in the same room as the infant increases the risk for SIDS. Physicians should educate new and prospective parents about the risk of tobacco smoke exposure during pregnancy and the first year of the infant's life.

Cigarette smoking and preeclampsia.

OBJECTIVE: To examine the relationship between cigarette smoking during pregnancy and the development of preeclampsia. METHODS: A case-control study compared the smoking histories of 110 nulliparous preeclamptic women and 115 healthy nulliparas aged 15-35 years who delivered at North Carolina Memorial Hospital. RESULTS: Unconditioned logistic regression relating smoking during pregnancy to preeclampsia yielded an odds ratio of 0.71 (95% confidence interval 0.33-1.50) when adjusting for working during pregnancy, alcohol use, medication use, contraceptive choices with the father of the index pregnancy, and family history of preeclampsia. There was no evidence of a dose-response effect of reduced risk for heavier smokers. CONCLUSIONS: Despite major methodologic improvements from previous studies, including rigorous diagnostic criteria for preeclampsia, a negative, non-statistically significant association persisted between cigarette smoking during pregnancy and preeclampsia, similar in magnitude to that of previous reports.

Albumin levels as a predictor of mortality in the healthy elderly.

Serum albumin levels probably predict subsequent mortality in the elderly, but it is not clear whether this is independent of disease. A 3 year prospective study of 2342 healthy non-institutionalized men and women aged 50-89 years old, residing in Rancho Bernardo, California, confirmed the following findings. Serum albumin levels decreased with increasing age in both men and women, and this association was independent of health status. In addition, for every standard deviation decrease in albumin, the relative odds of dying was 1.24 (p = 0.04), after adjusting for age, sex and lifestyle factors such as smoking, exercise and alcohol consumption. Separating the study sample into those who did and did not report disease at baseline did not appreciably alter these findings. Most of the albumin levels of the older adults (70-89) fall within the normal and narrow range of the younger adults (50-69), nevertheless, albumin levels predict outcome independent of known disease. The albumin-early mortality association suggests that serum albumin levels are a predictor for subclinical disease in the healthy elderly.

An epidemiologic study of contraception and preeclampsia.

The primary hypothesis of this study was that contraceptive methods that prevent exposure to sperm and seminal fluid (condoms, diaphragms, spermicides, withdrawal) are associated with an increased risk of developing preeclampsia during the subsequent pregnancy. A case-control study was conducted comparing the contraceptive and reproductive histories of 110 primiparous women with preeclampsia with 115 pregnant women without preeclampsia, aged 15 to 35 years, who gave birth at North Carolina Memorial Hospital, Chapel Hill, between 1984 and 1987. Controls were frequency matched to cases by age, race, and distance from the hospital. Unconditional logistic regression analysis indicated a 2.37-fold (95% confidence interval, 1.01 to 5.58) increased risk of preeclampsia for users of contraceptives that prevent exposure to sperm. A dose-response gradient was observed, with increasing risk of preeclampsia for those with fewer episodes of sperm exposure. These results were supportive of the hypothesis that birth control methods that prevent sperm exposure may play a role in the etiology of preeclampsia.