Maternal Cigarette Smoking during Pregnancy: A Risk Factor for Childhood Strabismus

Strabismus is a common ophthalmologic disorder in children that can result in permanent visual loss. A population-based case-control study was conducted to investigate the association between childhood strabismus and prenatal risk factors including maternal smoking. All incident cases of strabismus diagnosed during a 21-month period, from January 1, 1985, to September 30, 1986, in nine metropolitan area pediatric ophthalmology centers were selected for study (n=377). Controls were children born on the same day and in the same hospital as the cases (n=377). Data collection included an interview with the biologic mother and abstraction of obstetric and neonatal birth records. Cigarette smoking was associated with esotropia and but not exotropia for those women who smoked throughout pregnancy (odds ratio, 1.8, 95% confidence interval, 1.1 to 2.8, and odds ratio, 1.4, 95% confidence interval, 0.6 to 3.1, respectively). The relative risk for strabismus was not elevated for women who quit smoking before pregnancy or during pregnancy, nor was there evidence of a dose response. The effect of maternal smoking on risk of esotropia was modified by birth weight and gestational age. The association of maternal smoking throughout pregnancy and esotropia was strongest for children who weighed less than 2500 g (odds ratio, 8.2, 95% confidence interval, 1.1 to 62.7) and 3500 g or more at birth (odds ratio, 5.6, 95% confidence interval, 2.1 to 15.4). Exposure to secondary smoke during pregnancy increased the risk of strabismus only when the mother smoked. © 1992, American Medical Association. All rights reserved

Agreement between maternal interview- and medical record based gestational age

Agreement between maternal interview- and medical record-based gestational age was assessed by using data from a case-control study of childhood strabismus. The sample consisted of 383 cases of strabismus and their age-matched controls, diagnosed between 1985 and 1986 in Baltimore, Maryland, who were under age 7 years when diagnosed. Medical record-based gestational age was derived, in order of priority, from early ultrasound examination, time from the last menstrual period, pediatric examination, and obstetric examination. The intraclass correlation coefficient, kappa, and mean difference were used to compare agreement between maternal interview- and medical record-based gestational age by maternal and pregnancy characteristics and characteristics related to study design. Overall, 86 percent of mothers were within 2 weeks of the gestational age reported in the medical record. The intraclass correlation coefficient comparing maternal and medical record-based gestational age was 0.83 (95% confidence interval 0.80-0.86). Agreement was positively associated with shorter length of recall, low birth order, and having a neonatal illness related to prematurity. Agreement was poor among mothers of healthy preterm infants. There was a weak positive association between recall and some sociodemographic covariates. There was greater misclassification of prematurity in the controls than in the cases. The results suggest that, in general, women recall gestational age well, which supports the use of gestational age derived from maternal interviews. Am J Epidemiol 1992; 136: 566-73. © 1992 by The Johns Hopkins University School of Hygiene and Public Health

Infertility and Early Pregnancy Loss

The inability to achieve a recognized pregnancy may result from either failure of conception or implantation or an early postimplantation loss. Recently, a highly sensitive and specific assay for urinary human chorionic gonadotrophin (hCG) has enabled researchers to detect subclinical pregnancy losses. We used this assay to detect early pregnancy in a cohort of working women with and without fertility problems. One hundred forty eight female volunteers completed interviews, daily diaries an collected daily urine specimens for an average of seven months. The urine specimens were assayed for ovarian steroid hormones and hCG. Generalized estimating equations were used to estimate variance-corrected relative risks. There were 679 menstrual cycles at risk for pregnancy contributed by 124 of the women. Women with evidence of subfertility before or during the study period had a rate of early pregnancy loss of 70 percent compared to 21 percent of women without fertility problems (relative risk 2.63, 95%confidence interval 1.82-3.83. The risk of pregnancy loss associated with subfertility increased with age, and remained the same in women treated with clomiphene citrate. These results suggest that subfertile women have increased subclinical pregnancy losses regardless of fertility treatment, and the association between reduced fertility and advancing age may in part be related to early pregnancy loss.This study was supported by the International Business Machine Corporation

Infertility and Early Pregnancy Loss

The inability to achieve a recognized pregnancy may result from either failure of conception or implantation or an early postimplantation loss. Recently, a highly sensitive and specific assay for urinary human chorionic gonadotrophin (hCG) has enabled researchers to detect subclinical pregnancy losses. We used this assay to detect early pregnancy in a cohort of working women with and without fertility problems. One hundred forty eight female volunteers completed interviews, daily diaries an collected daily urine specimens for an average of seven months. The urine specimens were assayed for ovarian steroid hormones and hCG. Generalized estimating equations were used to estimate variance-corrected relative risks. There were 679 menstrual cycles at risk for pregnancy contributed by 124 of the women. Women with evidence of subfertility before or during the study period had a rate of early pregnancy loss of 70 percent compared to 21 percent of women without fertility problems (relative risk 2.63, 95%confidence interval 1.82-3.83. The risk of pregnancy loss associated with subfertility increased with age, and remained the same in women treated with clomiphene citrate. These results suggest that subfertile women have increased subclinical pregnancy losses regardless of fertility treatment, and the association between reduced fertility and advancing age may in part be related to early pregnancy loss.This study was supported by the International Business Machine Corporation

Occupational lead exposure and strabismus in offspring: A case-control study

The authors conducted a population-based case-control study to investigate the association between strabismus and parental occupational lead exposure. Cases were children diagnosed with nonrestrictive strabismus between 1985 and 1986 at Baltimore, Maryland-area pediatric ophthalmology practices and clinics (n = 377). Controls were matched for age and hospital of birth (n = 377). Jobs held by parents were assessed for lead exposure by industrial hygienists. The time window for lead exposure was defined as the period from conception through age 9 months. The unadjusted odds ratio for maternal lead exposure and the esotropic form of strabismus was 2.6 (95% confidence interval (Cl) 0.4-27). Unadjusted odds ratios for paternal occupational lead exposure and esotropia were 1.0 (95% Cl 0.5-2.1) for low exposure, 2.1 (95- Cl 0.9-5.3) for moderate exposure, and 1.2 (95% Cl 0.4-3.3) for high exposure. The study results suggest the possibility of a weak association between paternal lead exposure and strabismus in offspring. Am J Epidemiol 1991 ;133:351-6. © 1991 by The Johns Hopkins University School of Hygiene and Public Health

Injury Prevalence Among Children and Adolescents With Mental Retardation

Childhood injuries lead to increased morbidity and result in significant costs to public insurance programs. People with mental retardation, most of whom are covered by Medicaid, are at high risk for injury, which has implications for community inclusion, a central policy goal. Medicaid data from inpatient, outpatient, and long-term care settings represent an important new resource for injury surveillance in this population. Injury prevalence for 8.4 million Medicaid-eligible children in 26 states was measured using 1999 eligibility and claims data; 36.9% Medicaid beneficiaries ages 1 to 20 with mental retardation had at least one injury claim as compared with 23.5% of those without mental retardation. Prevalence rates are reported by gender and age for a variety of injury types