Mortality, major neurological handicaps--including mental retardation, cerebral palsy and epilepsy--educational subnormality and height at 14 years of age were studied by birth weight percentiles in a birth cohort of 12 000 children from northern Finland. Infant mortality was significantly higher below the mean -2 SD, 10th and 25th percentiles, than in the median class, from 25th to 75th percentiles, but mortality from one to 14 years only in the lowest weight class. Educational subnormality, including mental retardation +/- some other handicap, was highly significantly more frequent in all the percentile classes lower than the median class but showed no significant tendency to be less frequent in the percentiles over the median. It was also highly significantly more frequent among the preterm than the term infant. The number of children with a major neurological handicap but normal school performance did not vary significantly by birth weight percentiles or by gestational age. Height at 14 years increased significantly by birth weight percentiles. The height of the boys with birth weight mean - and +2 SD was nevertheless within the 25th-75th percentiles for height at 14 years in general, while the height of the girls came close to these percentile limits. The preterm infants were significantly shorter than the term infants at 14 years.
OBJECTIVE--To investigate long term mortality among women who smoked during pregnancy and those who stopped smoking. DESIGN--A follow up of a geographically defined cohort from 1966 through to 1993. SUBJECTS--11,994 women in northern Finland expected to deliver in 1966, comprising 96% of all women giving birth in the area during that year. Smoking habits were recorded during pregnancy but not later. MAIN OUTCOME MEASURE--Mortality by cause (571 deaths). RESULTS--The mortality ratio adjusted for age, place of residence, years of education and marital status was 2.3 (95% confidence interval 1.8 to 2.8) for the women who smoked during pregnancy and 1.6 (1.1 to 2.2) for those who stopped smoking before the second month of pregnancy, both compared with non-smokers. Among the smokers the relative mortality was higher for typical diseases related to tobacco intake, such as respiratory and oesophageal cancer and diseases of the cardiovascular and digestive organs and also for accidents and suicides. CONCLUSION--The risk of premature death seems to be higher in women who smoke during pregnancy than in other women who smoke. This may be explained either by the low proportion of those who stop later and the high proportion of heavy smokers or by other characteristics of these subjects that increase the risk.
BACKGROUND: Maternal exposure to influenza epidemics during pregnancy may increase the risk of schizophrenia in the offspring. We investigated the association between central nervous system (CNS) infections defined prospectively up to the age of 14, and later onset of schizophrenia and other psychoses in the 1966 birth cohort in Northern Finland, which covers 96% of all births in the area during that year. METHODS: Data regarding CNS infections were collected 1966-1980. Registered diagnoses of psychoses in 1982-1993 were validated on DSM-III-R criteria. RESULTS: Out of 11,017 subjects, 145 had suffered a CNS infection during childhood, 102 of them a viral infection, 76 had DSM-III-R schizophrenia and 53 some other psychosis. Four cases of schizophrenia had suffered viral CNS infection and two cases of other psychosis bacterial infection. When neurological abnormalities and father's social class were adjusted odds ratio (OR) of schizophrenia after viral CNS infection was 4.8 (95% confidence intervals [CI] : 1.6-14.0); the other significant risk factors being intelligence quotient (IQ)
The association of perinatal events, childhood epilepsy, and central nervous system trauma with juvenile delinquency was studied prospectively in a geographically defined population of 5966 males in northern Finland. Those who had obtained a criminal record up to the age of 22 years, totalling 355, or 6.0%, were defined as delinquents. The incidence of delinquency was not increased in males with a birth weight less than 2500 g or greater than 4000 g, preterm births
The study addresses the characteristics potentially predictive of non-response to a health survey among 2500 24-year-old males, on whom a notable amount of other data was available. The overall non-response rate was 40%, part of which was due to the unreachability of some subjects: 4% of the questionnaires were returned because of unknown addresses. Some (n = 39) of the respondents had concealed the identification number in the questionnaire, which made it impossible to link these data to those collected before in their cases. We were therefore able to use effectively the data on 1450 (58%) responding subjects in this paper. Failure to respond was more common among the subjects who had lived in towns in their youth, had not grown up in a complete family, whose socioeconomic status of the family was unknown, and whose mother was young and had a low educational level. Poorer-than-average school performance at elementary school was also predictive of a high non-response rate. Non-response was heavily associated with previous non-response to a health inquiry. Some aspects of health and behaviour in adolescense, such as smoking at the age of 14, were related to non-response to this survey, too. The non-response was higher than average among those subjects who had suffered from mental disorders (serious mental disorders, less serious mental disorders such as neurotic disorders, adjustment reactions, and psychosomatic disorders and mental retardation). The young men who were employed, were students or were doing military service at the age 24 responded better than those who were unemployed or at disability pension.
STUDY OBJECTIVE: To examine the association between body height, body mass index (BMI), and mortality in fertile women of childbearing age. DESIGN: A prospective cohort study with a 29 year mortality follow up. SETTING AND PARTICIPANTS: A cohort of women (n = 11,997) expected to deliver during 1966 in two northern provinces of Finland. Data on height and pre-pregnancy weight, collected with those on sociodemographic characteristics and smoking by questionnaire at the third trimester, were provided by 91% of the participants. Follow up for mortality using national registries was from delivery until the end of 1994. MAIN RESULTS: Height had a 'U' shaped association with total mortality over the whole follow up time. In women who were shorter than average, the death rate from cardiovascular diseases was increased and in taller women this was true for tumours. Compared with the women of 'normal weight' (BMI 21 to
In a 1-year birth cohort from the two northernmost provinces in Finland, Oulu and Lapland which comprised of 12 058 liveborn infants, the total number of children affected with cerebral palsy (CP) was 69. The cumulative incidence up to the age of 14 years was 5.7 per thousand. A prenatal aetiology was present in 32%, a perinatal aetiology in 36% and a postnatal aetiology in 19% whereas in 13.0% of the cases the cause remained untraceable. A total of 50 children (73%), had 1 or more additional handicaps. Mental retardation (IQ less than 85) was present in 70%, epilepsy in 48%, a visual defect in 19% and impaired hearing in 7%. The impact of the total handicaps is also illustrated by the fact that only 33% of the children were able to attend a normal school. The incidence of 5.7 per thousand recorded here is clearly higher than in studies from several other countries, as the cumulative incidence is usually reported to vary between 2 and 3 per thousand.
The acceptability of pregnancies was studied in two birth cohorts in Northern Finland which represent 96% of all births in the region in 1966 (12,068 births) and 99% (9362 births) in 1985-1986. The numbers of women of fertile age in the area during these years were 148,000 and 158,000, so that fertility may be said to have fallen from 81 to 59 per 1000. The pregnancy was wanted in 63.0% of cases and unwanted in 12.2% in 1966, the rest being classified as accepted later. The corresponding figures in 1985-1986 were 91.8% and 1.0%. The latter figures changed very little when maternal age, parity and social class were standardized to the 1966 levels. Acceptability was connected with age, in that the age groups in which childbearing was most frequent, 20-25 years in 1966 and 26-30 years in 1985-1986, had the highest incidence of desired pregnancies. In spite of the fact that there were 1.4 times as many births per woman aged 15-49 years in the former cohort, more wanted children were born to the age group 25-34 years in the latter cohort. The percentage of wanted pregnancies also varied with the woman's parity, social class and marital status. The children in the 1966 cohort were followed until the age of 14 and the incidences of cerebral palsy (CP) and mental retardation (IQ less than 71) were 3.2 times higher among the unwanted children than among the wanted ones.(ABSTRACT TRUNCATED AT 250 WORDS)
The study is based on two birth cohorts from the years 1966 and 1985-1986. Perinatal mortality of twins has fallen over 20 years from 9.2% to 3.1%. Improvement is particularly remarkable in neonatal mortality (less than 28 days) of preterm (less than 34 gestational weeks) twins, from 47.4% to 8.6%, whereas the incidence of stillbirths has not fallen greatly. The proportion of preterm births has not fallen significantly, 48.4% vs. 38.1%. Many factors, considered favourable to the course and outcome of pregnancy have improved simultaneously: women are taller, less overweight, and more educated; pregnancies are wanted and sick and maternity leave provisions have improved. The follow-up of twin pregnancies and deliveries has been centralized and is more effective. In particular, neonatal care is also better than 20 years ago. The prognosis of twins has improved in parallel with the singletons, but the perinatal mortality is still approximately four time and the incidence of prematurity ten times more than in singletons.