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Stein Tore Nilsen

Publications and source records attributed to Stein Tore Nilsen.

8 recordsLinked to original sources

[The breakthrough series on Cesarean section].

BACKGROUND: The "breakthrough series" on caesarean section was organised in Norway in 1998/99 in response to professional concerns about rising caesarean section rates and the public debate about the topic. The aim was to gain more information and to reduce the inter-hospital variation of caesarean section rates. MATERIAL AND METHODS: Detailed information about 3000 caesarean sections (70% of all caesarean sections in Norway during the study period of 7 months) was collected. Twenty-four departments participated and were involved in a quality-improvement process. RESULTS: In 1998 the caesarean section rate among the participating departments was 13.5% (inter-hospital variation 8.6% to 20.4%). In 2002 the rate was 15.7% (inter-hospital variation 11.0%-24.5%). The most frequent indications were fetal stress, prolonged labour, previous caesarean section, breech presentation and maternal request. Of the women with a previous caesarean section, 45.5% had a new caesarean section in their next pregnancy. Complications occurred in 21% of all procedures; risk factors were general anaesthesia, low gestational age, fetal macrosomia and degree of cervical dilation. INTERPRETATION: The project highlighted quality improvement work and interdisciplinary working processes and led to more knowledge about caesarean section. The inter-hospital variation was unchanged four years after the project.

Cesarean Section↗

Breech delivery and intelligence: a population-based study of 8,738 breech infants.

OBJECTIVE: Long-term intellectual performance in breech-presented infants may be negatively affected by vaginal delivery. We evaluated the effect of presentation at birth and delivery mode on intellectual performance at age 18 years in a nationwide population study. METHODS: We studied 8,738 male infants in breech and 384,832 males in cephalic presentation registered in the Medical Birth Registry of Norway, 1967-1979, and linked to data registered at the National Conscript Service, 1984-1999. Test scores of intelligence testing at conscription were presented as standard nine ("stanine") scores. Mean stanine scores and odds ratios of low score were computed and adjusted for birth order, maternal age, and education. RESULTS: Mean stanine score was slightly higher among breech-presented males than among cephalic-presented males (5.26 versus 5.22, P = .05), whereas after adjustment the difference disappeared (P = .3). Breech-presented infants had lower mean scores if delivered by cesarean compared with vaginal breech delivery (P = .03), and cephalic-presented males scored lower if their mothers had a cesarean delivery instead of a vaginal delivery (P < .001). Comparing cesarean and vaginal delivery in breech births, the odds ratio of having a stanine score less than or equal to 3 was 1.12 (95% confidence interval 0.92,1.36), after adjustment for confounding factors. CONCLUSION: Presentation at birth did not affect adult intellectual performance. Cesarean delivery of breech-presented infants did not improve adult intellectual performance when compared with a vaginal delivery. The excess perinatal hazards of breech-presented infants with a vaginal delivery were not reflected in adult intellectual performance.

Adolescent↗

Size at birth and gestational age as predictors of adult height and weight.

BACKGROUND: Both birth length and birth weight are associated with height in adulthood and may have independent contributions to adult body size, but the effects of gestational age on these associations have not been fully evaluated. Our objective was to examine the independent contributions of gestational age, and of length and weight at birth, on adult (age 18 years) height and weight, with a special focus on the effects of being born preterm. METHODS: In this nationwide cohort study, records of 348,706 male infants included in the Medical Birth Registry of Norway (1967-1979) were linked to the Norwegian Conscripts Service (1984-1999). Complete follow-up information, including deaths, emigration, and disability pension, was obtained for 94%. We analyzed length and weight at birth using standardized (z-scores) values and stratified by gestational age. RESULTS: The positive association between birth length and adult height was stronger than between birth weight and adult weight (R = 7-9% compared with <0.1%, respectively). The strongest associations were seen among those born at gestational age 39 to 41 weeks. The effects of birth length on adult height, and of birth weight on adult weight, were considerably less among preterm births than among term births. Length and weight at birth each contributed independently to adult stature and body weight. The increase in adult weight per relative birth weight category was greatest for infants who were both heavy and long at birth. CONCLUSIONS: Birth length is perhaps a better predictor of adult height and weight than birth weight, and should be considered as a possible risk factor for adult morbidity and mortality.

Adolescent↗

Maternal and fetal variants of genetic thrombophilias and the risk of preeclampsia.

BACKGROUND: A woman's thrombophilic genes may increase her risk of preeclampsia in pregnancy. Vascular conditions of the placenta related to thrombophilic genes of the fetus could also be relevant for preeclampsia. The case-parent triad study design provides separate estimation of maternal and fetal genes. METHODS: We recruited 92 mother-father-child triads of preeclamptic pregnancies from a birth clinic in Stavanger, Norway. All parents were of Norwegian origin. Maternal, paternal, and fetal DNA were genotyped for the methylenetetrahydrofolate reductase (MTHFR) C677T and Factor V Leiden (FVL) G1691A SNPs. Estimation of the relative risk (RR) associated with fetal and maternal genetic variants was performed by log-linear models. RESULTS: There was no indication of an effect of the child's FVL alleles on preeclampsia risk. For case babies with 2 copies of the variant allele, the association with the MTHFR variant was inconclusive (RR = 1.6; 95% confidence interval [CI] = 0.6-4.3). Case mothers who were homozygous for the MTHFR variant had a relative risk of 2.0 (CI = 1.0-4.1) assuming a recessive gene effect. A 2.5-fold risk (CI = 1.1-5.7) of preeclampsia was estimated when the mother carried one copy of the FVL. Among mothers homozygous for the MTHFR variant, the relative risk of the FVL variant was 4.6-fold (CI = 1.0-21). CONCLUSIONS: We found little evidence of an effect of the child's MTHFR or FVL alleles on the risk of preeclampsia. Our estimates of effects of maternal MTHFR and FVL alleles were consistent with estimates from case-control studies. The case-parent triad design may be a useful tool for studies of pregnancy complications such as preeclampsia.

Adult↗

Relationship of insulin-like growth factor-I and insulin-like growth factor binding proteins in umbilical cord plasma to preeclampsia and infant birth weight.

OBJECTIVE: To determine whether preeclampsia influences insulin-like growth factor-I (IGF-I), insulin-like growth factor binding protein-1 (IGFBP-1), and insulin-like growth factor binding protein-3 (IGFBP-3), independent of its effect on birth weight. METHODS: Cord blood was collected in 12,804 consecutive deliveries. We identified 258 preeclamptic pregnancies that were subclassified as mild or severe and early or late. For comparison, 609 control pregnancies were selected. Fetal growth was expressed as the ratio between observed and expected birth weight, with adjustment for gestational age at birth. IGF-I, IGFBP-1, and IGFBP-3 were measured in umbilical plasma. The contribution of preeclampsia and birth weight to each measured factor was assessed by multiple linear regression analyses. RESULTS: Between mild preeclampsia and controls, there were no differences in IGF-I, IGFBP-1, and IGFBP-3. In severe and early onset preeclampsia, umbilical cord plasma IGF-I was approximately 50% lower, and IGFBP-1 was more than twice as high as in controls (both P <.01). At each birth weight level, IGF-I was lower and IGFBP-1 was higher in severe or early preeclampsia than among controls of similar weight. Birth weight and preeclampsia were, independent of each other, associated with IGF-I, whereas birth weight, but not preeclampsia, was associated with IGFBP-1, after adjustment for gestational age. CONCLUSION: Fetal growth restriction caused by severe or early preeclampsia is associated with lower umbilical levels of IGF-I than low birth weight caused by other conditions. Preeclampsia may contribute to the observed IGF-I reduction, either as part of the underlying causes of preeclampsia, or as a consequence of the disease.

Adult↗

Umbilical cord plasma leptin is increased in preeclampsia.

OBJECTIVE: The objective of this study was to compare umbilical cord plasma leptin between infants of mothers who experienced preeclampsia and infants of control subjects and to study the relation between cord plasma leptin and infant obesity, as indicated by ponderal index. STUDY DESIGN: On the basis of a population of approximately 13,000 deliveries, we compared cord plasma leptin from preeclamptic (n = 256 women) and control pregnancies (n = 607 women) after taking the differences in gestational age and ponderal index into account. RESULTS: Cord plasma leptin increased strongly with gestational age, both in the preeclampsia group and the control subjects (P <.01), but at each gestational age the preeclampsia group had higher leptin levels than control subjects (P <.01). Adjustment for the higher ponderal index among control subjects (P <.05) did not alter the difference in leptin levels between the groups. CONCLUSION: We found higher levels of umbilical cord plasma leptin in infants of mothers who had preeclampsia (compared with infants of control subjects) after adjusting for differences in gestational age, gender, and infant ponderal index.

Adult↗

Insulin-like growth factor I and leptin in umbilical cord plasma and infant birth size at term.

OBJECTIVE: To determine the independent contributions to infant birth size of insulin-like growth factor I (IGF-I) and leptin measured in umbilical cord plasma. METHODS: Umbilical cord blood was collected in 12 804 consecutive deliveries, and cord plasma from 585 singleton infants born at term after uncomplicated pregnancies was analyzed for leptin, IGF-I, and 2 IGF-binding proteins (IGFBP-1 and IGFBP-3). In multivariable analyses, we assessed maternal and infant covariates of leptin and IGF-I, and we evaluated the independent contribution of cord levels of leptin and IGF-I on infant birth size. RESULTS: Cord plasma levels of IGF-I were lower in women who reported smoking at the beginning of pregnancy compared with nonsmokers. In female infants, levels of IGF-I and leptin were higher than in male infants after adjustment for ponderal index and maternal factors. We found a strong parallel increase in umbilical IGF-I and leptin with increasing birth weight and birth length. For IGFBP-1, there was an opposite pattern: IGFBP-1 increased with decreasing birth size. The multivariable analysis, adjusted for length of gestation and maternal age, parity, prepregnancy weight, smoking during pregnancy, and offspring sex, showed that IGF-I and leptin, independent of each other, were associated with birth weight and birth length. CONCLUSIONS: Levels of IGF-I and leptin in umbilical cord plasma were higher in girls than in boys, but in both sexes, these 2 factors contributed independently and positively to birth weight and length. For IGFBP-1, high levels were associated with low birth weight and reduced length. If intrauterine growth is related to the risk of developing adult diseases, IGF-I, IGFBP-1, and leptin may be involved in the underlying processes.1131-1135 insulin like growth factors, leptin, umbilical cord plasma, birth weight.

Birth Weight↗