The eye in childhood. (65/4443)

Normal visual development is rapid during the first six months of life and continues through the first decade. Young children are uniquely sensitive to conditions that interfere with vision and visual development. Amblyopia, or functionally defective development of the central visual system, may be caused by common vision problems such as strabismus, uncorrected refractive errors and deprivation secondary to occlusion. Prematurity is especially associated with eye pathology, including retinopathy of prematurity, amblyopia, strabismus and refractive errors. When detected early, amblyopia and many other childhood vision abnormalities are treatable, but the potential for correction and normal visual development is inversely related to age. Since many affected children are asymptomatic, early detection of abnormal visual function requires effective screening throughout early childhood. Special considerations apply to screening examinations of children born prematurely.  (+info)

The influence of gestational age and smoking habits on the risk of subsequent preterm deliveries. (66/4443)

BACKGROUND: Previous preterm delivery and maternal smoking are associated with increased risks of preterm delivery. It is not known whether gestational age at the time of a preterm delivery is correlated with gestational age in successive preterm deliveries and whether changes in smoking habits influence the subsequent risk of preterm delivery. METHODS: We studied the associations among smoking habits, previous very preterm or moderately preterm delivery (before 32 weeks and at 32 to 36 weeks, respectively), and the risk of a subsequent very preterm or moderately preterm delivery in a population-based cohort of 243,858 women in Sweden between 1983 and 1993. The results were adjusted for covariates known to be associated with preterm delivery. RESULTS: The odds ratios for very or moderately preterm delivery in a subsequent pregnancy among women with a previous very preterm delivery, as compared with women who had a previous term delivery, were 12.4 (95 percent confidence interval, 9.1 to 17.0) and 7.1 (95 percent confidence interval, 6.0 to 8.4), respectively. Among women with a previous moderately preterm delivery, the corresponding odds ratios were 2.3 (95 percent confidence interval, 1.9 to 3.0) and 5.9 (95 percent confidence interval, 5.5 to 6.3), respectively. The odds ratios for a very preterm second delivery among the women who smoked 1 to 9 cigarettes per day and those who smoked 10 or more cigarettes per day, as compared with nonsmokers, were 1.4 (95 percent confidence interval, 1.1 to 1.7) and 1.6 (95 percent confidence interval, 1.3 to 2.0), respectively. The corresponding odds ratios for moderate preterm delivery were 1.3 (95% confidence interval, 1.2 to 1.4) and 1.5 (95 percent confidence interval, 1.4 to 1.6). The women who quit smoking between pregnancies were not at increased risk for very or moderately preterm delivery, whereas the women who started to smoke in the second pregnancy had the same risk as those who continued to smoke. CONCLUSIONS: The risk of a very preterm delivery in successive pregnancies is increased primarily among women with a previous very preterm delivery. Changes in smoking habits influence the risk of preterm delivery as well.  (+info)

Physical and nonphysical partner abuse and other risk factors for low birth weight among full term and preterm babies: a multiethnic case-control study. (67/4443)

This study sought to determine the risk of low birth weight from intimate partner abuse. The case-control design was used in a purposively ethnically stratified multisite sample of 1,004 women interviewed during the 72 hours after delivery between 1991 and 1996. Abuse was determined by the Index of Spouse Abuse and a modification of the Abuse Assessment Screen. Separate analyses were conducted for 252 full term and 326 preterm infants. The final multiple logistic regression models were constructed to determine relative risk for low birth weight after controlling for other complications of pregnancy. Physical and nonphysical abuse as determined by the Index of Spouse Abuse were both significant risk factors for low birth weight for the full term infants but not the preterm infants on a bivariate level. However, the risk estimates decreased in significance in the adjusted models. Although today's short delivery stays make it difficult to assess for abuse, it is necessary to screen for domestic violence at delivery, especially for women who may not have obtained prenatal care. The unadjusted significant risk for low birth weight that became nonsignificant when adjusted suggests that other abuse-related maternal health problems (notably low weight gain and poor obstetric history) are confounders (or mediators) that help to explain the relation between abuse and low birth weight in full term infants.  (+info)

Influence of perinatal factors on the onset of puberty in boys and girls: implications for interpretation of link with risk of long term diseases. (68/4443)

The authors examined the hypothesis that perinatal factors influence the onset of puberty. Children born as singletons in Uppsala, Sweden, in 1973-1977 were followed for height development before and during their school years (through 16 years of age). In all, 62 children born after preeclampsia, 129 born prematurely, 90 born small for gestational age, 175 born large for gestational age, 49 born short for gestational age, and 38 born tall for gestational age were compared with 688 "normal" children. Differences in age and height at puberty onset and age at menarche were analyzed using the t test and analyses of covariance. For boys, the mean age at puberty onset did not differ between normal boys and those with perinatal factors. Boys born small or short for gestational age were 4 cm shorter than normal boys, and those born large for gestational age were 3 cm taller than normal boys. Among girls, patterns for differences in height were similar. Girls born small for gestational age were 5 months younger than normal girls at the onset of puberty and menarche. Patterns of early childhood growth seemed to explain the relations between these perinatal factors and height and age at puberty. The authors conclude that body size at birth affects stature at puberty; in girls, smallness for gestational age is associated with earlier puberty. Associations between intrauterine exposures and disease risk may be confounded by, or mediated through, effects on adolescence.  (+info)

Recurrence of gestational age in sibships: implications for perinatal mortality. (69/4443)

The authors studied the extent to which preterm birth and perinatal mortality are dependent on the gestational ages of previous births within sibships. The study was based on data collected by the Medical Birth Registry of Norway from 1967 to 1995. Newborns were linked to their mothers through Norway's unique personal identification number, yielding 429,554 pairs of mothers and first and second singleton newborns with gestational ages of 22-46 weeks, based on menstrual dates. Siblings' gestational ages were significantly correlated (r = 0.26). The risk of having a preterm second birth was nearly 10 times higher among mothers whose firstborn child had been delivered before 32 weeks' gestation than among mothers whose first child had been born at 40 weeks. However, perinatal mortality in preterm second births was significantly higher among mothers whose first infant had been born at term, compared with mothers whose firstborn child was delivered at 32-37 weeks. Since perinatal mortality among preterm infants is dependent on the gestational age in the mother's previous birth, a common threshold of 37 weeks' gestation for defining preterm birth as a risk factor for perinatal death may not be appropriate for all births to all mothers.  (+info)

Incidence of neonatal seizures in Harris County, Texas, 1992-1994. (70/4443)

This study estimated the incidence of clinical neonatal seizures among infants born between 1992 and 1994 in Harris County, Texas, a county with a large and ethnically diverse population. Infants with neonatal seizures were ascertained from four sources: hospital discharge diagnoses, birth certificates, death certificates, and a study of neonatal seizures conducted concurrently with this study at a large tertiary care center in Houston, Texas. There were 207 cases of clinical neonatal seizures among 116,048 live births (an incidence of 1.8 per 1,000 live births). The incidence was highest among infants weighing less than 1,500 g (19/1,000) and decreased as birth weight increased. There was no significant difference in incidence by ethnicity. Twenty-six percent of the seizures (54/207) occurred after the infants had been discharged from the hospital where they were born. The incidence of neonatal seizures in Harris County was lower than the incidence reported recently for Fayette County, Kentucky, for 1985-1989 (3.5/1,000) and for Newfoundland, Canada, for 1990-1995 (2.5/1,000), but was higher than the incidence estimated for Rochester, Minnesota, for 1935-1984 (1/1,000).  (+info)

Measurement of upper esophageal sphincter tone and relaxation during swallowing in premature infants. (71/4443)

Upper esophageal sphincter (UES) motor function has not been previously evaluated in premature infants. The motor patterns associated with tonic activity and swallow-related relaxation of the UES were recorded for 1 h after completion of gavage feeding in 11 healthy preterm neonates (postmenstrual age 33-37 wk) with a micromanometric assembly, which included a sleeve sensor specifically adapted for UES recordings. A clearly defined UES high-pressure zone was observed in all premature infants studied. Resting UES pressure ranged from 2.3 to 26.2 mmHg and was higher during periods of irritability and apparent discomfort. During dry swallows, UES pressure relaxed from a resting pressure of 28.2 +/- 4.0 mmHg to a nadir of 1.1 +/- 3.3 mmHg. The mean UES relaxation interval (the time from relaxation onset to relaxation offset) was 0. 31 +/- 0.11 s. We conclude that in premature infants >/=33 wk postmenstrual age the motor mechanisms regulating UES resting pressure and the onset of UES relaxation are well developed.  (+info)

Effect of prenatal care on infant mortality rates according to birth-death certificate files. (72/4443)

Infant mortality has decreased nationwide; however, our national rates still log behind those of other industrialized countries, especially the rates for minority groups. This study evaluates the effect of prenatal care and risk factors on infant mortality rates in Chicago. Using linked infant birth and death certificates of Chicago residents for 1989-1995, a total of 5838 deaths occurring during the first year of life were identified. Birth certificate variables, especially prenatal care, were reviewed. Variables were compared by stratified analysis. Pearson chi 2 analysis and odd ratios (ORs) were computed. Infant mortality rate (IMR) in Chicago decreased from 17 in 1989 to 12.6 in 1995 (P < .0001). Some factors increased IMR several fold: prematurity (OR 17.43), no prenatal care (OR 4.07), inadequate weight gain (OR 2.95), African-American ethnicity (OR 2.55), and inadequate prenatal care (OR 2.03). Compared with no care, prenatal care was associated with lower IMR; however, early care was associated with higher IMR and ORs than later care. These results demonstrate prenatal care is associated with lower IMR; however, compared with late prenatal care, early care does not improve IMR. Further studies should evaluate whether improving the quality of care improves IMRs.  (+info)