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Tine Brink Henriksen

Publications and source records attributed to Tine Brink Henriksen.

At least 19 recordsLinked to original sources
PubMed2006

Duration of pregnancy in relation to seafood intake during early and mid pregnancy: prospective cohort.

We examined the association between exposure to seafood intake during two periods of pregnancy on the one hand and risks of preterm delivery and postterm delivery on the other. In a prospective cohort of 8729 pregnant Danish women, we assessed frequency of fish meals during the first and second trimester of pregnancy by questionnaires completed around gestation weeks 16 and 30, respectively. When fish intake was based solely on intake reported for the early period of pregnancy, mean gestation length was shorter by 3.91 (95% CI: 2.24-5.58) days and odds of preterm delivery were increased 2.38 (1.23-4.61) times in those who never consumed fish (n = 308) vs. those who consumed both fish as main meal and fish in sandwiches at least once per week (n = 785). These measures were similar when fish intake was based solely on intake reported for mid-pregnancy. In the subgroup of women reporting same intake in the two trimesters, those who never consumed fish (n = 165) had 8.57 (5.46-11.7) days shorter mean gestation and 19.6 (2.32-165) times increased odds of preterm delivery, compared to high fish consumers (n = 127); odds of elective and postterm delivery were reduced by a factor 0.33 (0.11-1.02) and 0.34 (0.12-0.95), respectively, in zero fish consumers. All analyses were adjusted for potential confounding by factors such as maternal smoking, height, and prepregnant weight. We conclude that never consuming fish in the first two trimesters of pregnancy was an extremely strong risk factor for preterm delivery but was also associated with reduced risks of elective delivery and postterm delivery.

Cohort Studies↗
PubMed2006

Stillbirth and slow metabolizers of caffeine: comparison by genotypes.

BACKGROUND: Cytochrome P4501A2 (CYP1A2) and N-acetyltransferase 2 (NAT2) are key enzymes in the metabolism of caffeine. The polymorphism of these genes facilitates the detection of fast and slow metabolizers, and if caffeine is causally related to stillbirth, we expect slow metabolizers to have a higher risk of stillbirth at any given intake of caffeine. Gluthatione S-transferase alpha1 (GSTA1) may also be active in the metabolism of caffeine as it conjugates glutathione to aromatic amines. Our study, therefore, included analyses of the association between GSTA1 and stillbirth. METHODS: A nested case non-case study among women who participated in the Danish National Birth Cohort: 142 cases of singleton stillbirths and 157 controls of singleton live births. RESULTS: Slow oxidizer status (CYP1A2), slow acetylator status (NAT2), and low activity of GSTA1 were not individually associated with the risk of stillbirth [odds ratio (OR) = 1.06, 95% confidence interval (95% CI) 0.67-1.67, OR = 0.95, 95% CI 0.60-1.51, and OR = 1.42, 95% CI 0.88-2.28, respectively]. We did, however, observe that subjects with a combination of slow CYP1A2, slow NAT2, and low GSTA1 genes had almost a 2-fold risk of stillbirth compared with subjects with other combinations of genotypes. CONCLUSIONS: We found no link between any single genotype and the risk of stillbirth. An association between a combination of genotypes and stillbirth was discovered. Caffeine may be causally related to stillbirth, but larger studies using Mendelian randomization are needed to verify this.

Acetyltransferases↗
PubMed2006

Associations between socio-economic factors and the use of prescription medication during pregnancy: a population-based study among 19,874 Danish women.

OBJECTIVE: To examine the association between socio-economic factors and use of prescription medication during pregnancy in a population of Danish women. METHODS: This was a population-based cohort study. Using record linkage from public administrative registries, we described the use of prescription medication during pregnancy and the financial and educational resources for each pregnant woman in the cohort. RESULTS: The analyses included all 19,874 primiparous women delivering singletons in North Jutland county, Denmark, in 1991-1998. We identified 24,243 prescriptions filled by the women during their pregnancies. The highest overall prescription medication use was among women with basic schooling (OR 1.3; 95% CI 1.2-1.4), and lowest among women with the highest education (OR: 0.8; 95% CI 0.7-0.9) compared with women who had vocational education. Stratified analysis of therapeutic subgroups revealed that socio-economic factors were associated with the use of anti-infective and anti-asthmatic medications during pregnancy. CONCLUSION: Maternal educational level, and to a lesser degree household income, paternal educational level and cohabitation status, was associated with the use of prescription medication during pregnancy. However, the analyses did not take into account important clinical variables such as maternal illness, and the results could be affected by differential misclassification of exposure information, by confounding or chance.

Adult↗
PubMed2006

Cigarette smoking during pregnancy and hyperactive-distractible preschooler's: a follow-up study.

AIM: To study the association between intrauterine exposure to tobacco smoke and behavioural disorders in preschool children, primarily symptoms of inattention, hyperactivity and impulsivity but also hostile-aggressive and anxious-fearful symptoms. METHODS: We conducted a follow-up study in 1355 singletons born to Danish-speaking mothers. Information on smoking habits during pregnancy and other lifestyle factors was obtained from self-administered questionnaires filled in during second and third trimester. Approximately 3.5 years later, the parents provided information on their child's behaviour using the self-administered Preschool Behaviour Questionnaire. The children were categorized into three not mutually exclusive behaviour groups: hyperactive - distractible (13.6%), hostile-aggressive (4.6%), and anxious-fearful (6.4%) children. RESULTS: Compared with children of non-smokers, children born to women who smoked 10 or more cigarettes per day had a 60% increased risk of hyperactivity and distractibility perceived by the parents (OR 1.6; 95% CI 1.0-2.3; P < 0.05). The results were adjusted for maternal lifestyle factors and socioeconomic characteristics. Additional adjustment for perinatal factors and parental psychiatric hospitalization did not change the results substantially (OR 1.7; 95% CI 1.1-2.6). We found no statistically significant association between maternal smoking in pregnancy and hostile-aggressive and anxious-fearful behaviour in the offspring. CONCLUSION: Exposure to tobacco smoke in utero was associated with hyperactive-distractible behaviour in preschool children.

Child Behavior Disorders↗
PubMed2006

Does low participation in cohort studies induce bias?

BACKGROUND: Participation rates in large cohort studies have decreased during the last 2 decades. The consequences of this trend for relative risk estimation are unknown. METHODS: The impact of a low participation rate (30%) on the Danish National Birth Cohort was examined among 49,751 women from the source population, including 15,373 participants in the cohort study. On the basis of independent data collection, we estimated odds ratios (ORs) in the source population and among participants for 3 exposure-risk associations: (a) in vitro fertilization and preterm birth, (b) smoking during pregnancy and birth of a small-for-gestational-age infant, and (c) prepregnancy body mass index and antepartum stillbirth. The effect of nonparticipation was described by a relative odds ratio (ROR), calculated as the OR(participants)/OR(source population). Two methods for calculation of confidence intervals for the relative odds ratio also were assessed. RESULTS: The effect of nonparticipation on the selected ORs was small. The relative ORs were close to one and the bias was never larger than 16%, although some of the confidence intervals were wide. The 2 methods for calculation of confidence intervals gave very similar results and a small simulation study showed that the coverage probabilities were close to the 95% nominal level. CONCLUSION: For the 3 chosen associations, the ORs were not biased by nonparticipation. The results are reassuring for studies based on the Danish cohort and similar cohorts of pregnant women. The methodology used to compute confidence intervals for the relative odds ratios performed well in the scenarios considered.

Adult↗
PubMed2006

Gestational age and birth weight in relation to school performance of 10-year-old children: a follow-up study of children born after 32 completed weeks.

BACKGROUND: Children born extremely premature (<28 weeks) or with a very low birth weight (<1500 g) have a poorer school performance than children born at term with a normal birth weight. Much less is known about children of higher gestational ages and birth weights. We studied gestational age after 32 completed weeks and birth weight in relation to the child's school performance at the age of 10 years. METHODS: We performed a follow-up study of 5319 children born between January 1990 and June 1992. We got the information on birth weight and gestational age from birth registration forms; when the children were between 9 and 11 years of age, we gathered information about their school performance (reading, spelling, and arithmetic) from questionnaires completed by the parents and the children's primary school teachers. RESULTS: The association between birth weight and reading, as well as spelling and arithmetic disabilities, showed a graded relationship, with children who weighed <2500 g having the highest risks. Even children who weighed between 3000 and 3499 g had an increased risk of all 3 learning disabilities compared with children who weighed between 3500 and 4000 g. This association persisted after adjustment for potential cofounders and when the analyses were restricted to children born at term (39-40 weeks of gestation), suggesting that the association could not be explained by a low gestational age. Compared with children born at term, reading and spelling difficulties were more often found among children born at gestational age 33 to 36 weeks and 37 to 38 weeks, whereas there was no relation between gestational age and arithmetic difficulties. CONCLUSIONS: Gestational age and birth weight were associated with school performance in the 10-year-old child and the association extended into the reference range of both birth weight and gestational age.

Achievement↗
PubMed2005

The Danish National Hospital Register is a valuable study base for epidemiologic research in febrile seizures.

BACKGROUND AND OBJECTIVES: We examined the quality and completeness of the discharge diagnosis of febrile seizures in the Danish National Hospital Register (DNHR). METHODS: We invited all children born at the Department of Obstetrics, Aarhus University Hospital, Denmark, between January 1990 and April 1992, to participate in the study. We collected information on febrile seizures in March 2001 by mailing a questionnaire to the mothers. Reported febrile seizures were verified by telephone interviews or review of medical records. We linked the cohort to the DNHR by means of a unique civil registry number assigned to all Danish citizens at birth. Overall, 6,624 (73%) children participated in the study. RESULTS: We found that 323 (4.9%) children in the cohort had had febrile seizures, and 231 of those were registered in the DNHR (completeness: 71.5%, 95% CI: 66.3-76.4). Furthermore, we confirmed the diagnosis in 231 of 249 children registered with febrile seizures in the DNHR (predictive value of a positive registration: 92.8%, 95% CI: 88.8-95.7). CONCLUSION: The Danish National Hospital Register is a valuable tool for epidemiologic research in febrile seizures.

Child↗
PubMed2005

Coffee and fetal death: a cohort study with prospective data.

The authors conducted a cohort study within the Danish National Birth Cohort to determine whether coffee consumption during pregnancy is associated with late fetal death (spontaneous abortion and stillbirth). A total of 88,482 pregnant women recruited from March 1996 to November 2002 participated in a comprehensive interview on coffee consumption and potentially confounding factors in pregnancy. Information on pregnancy outcome was obtained from the National Hospital Discharge Register and medical records. The authors detected 1,102 fetal deaths. High levels of coffee consumption were associated with an increased risk of fetal death. Relative to nonconsumers of coffee, the adjusted hazard ratios for fetal death associated with coffee consumption of 1/2-3, 4-7, and > or =8 cups of coffee per day were 1.03 (95% confidence interval (CI): 0.89, 1.19), 1.33 (95% CI: 1.08, 1.63), and 1.59 (95% CI: 1.19, 2.13), respectively. Reverse causation due to unrecognized fetal demise may explain the association between coffee intake and risk of fetal death prior to 20 completed weeks' gestation but not the association with fetal loss following 20 completed weeks' gestation. Consumption of coffee during pregnancy was associated with a higher risk of fetal death, especially losses occurring after 20 completed weeks of gestation.

Abortion, Spontaneous↗
PubMed2005

Prepregnancy obesity and fetal death: a study within the Danish National Birth Cohort.

OBJECTIVE: To examine the association between high prepregnancy body mass index and fetal death, allowing for the effects of gestational age, weight gain, and maternal diseases in pregnancy. METHODS: Prepregnancy body mass index (BMI) and fetal death were examined in the Danish National Birth Cohort among 54,505 pregnant women who participated in a comprehensive interview during the second trimester. Pregnancy outcomes were obtained from registers and medical records. Cox regression analyses with delayed entry and time-dependent covariates were used to estimate the risk of fetal death. RESULTS: Compared with normal-weight women (18.5 < or = BMI < 25), the risks of fetal death among obese women (BMI > or = 30), expressed as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were as follows: before week 14: 0.8 (0.5-1.4), weeks 14-19: 1.6 (1.0-2.5), weeks 20-27: 1.9 (1.1-3.3), weeks 28-36: 2.1 (1.0-4.4), weeks 37-39: 3.5 (1.9-6.4), and weeks 40+: 4.6 (1.6-13.4). Overweight women (25 < or = BMI < 30) also experienced a higher risk after 28 weeks, and especially after 40 weeks of gestation (HR 2.9, 95% CI 1.1-7.7). Analysis of stillbirth (fetal death at 28+ completed weeks of gestation) indicated that the effects were not due to obesity-related diseases in pregnancy, nor was weight gain associated with stillbirth. The increased risk of stillbirth among overweight and obese women was partly attributable to inadequate placental function (crude odds ratios 2.1, 95% CI 1.0-4.4, and 5.2, 95% CI 2.5-10.9, respectively). CONCLUSION: Prepregnancy obesity was associated with an increasing excess risk of fetal death with advancing gestation, and placental dysfunction may be a possible contributing factor.

Adult↗
PubMed2005

Smoking during pregnancy and the risk for hyperkinetic disorder in offspring.

OBJECTIVE: Maternal smoking during pregnancy may increase the risk for behavioral disorders. The aim of this study was to investigate the association between smoking during pregnancy and hyperkinetic and attention-deficit/hyperactivity disorder in the offspring in a large population-based study. METHODS: This study was designed as a nested case-control study. Data were obtained from Danish longitudinal registers and included 170 children with hyperkinetic disorder and 3765 population-based control subjects, who were matched by age, gender, and date of birth. Potential confounders, including newborn characteristics, socioeconomic status, and family history of psychiatric illnesses, were evaluated by conditional logistic regression analyses. RESULTS: Women who smoked during pregnancy had a 3-fold increased risk for having offspring with hyperkinetic disorder compared with nonsmokers. Socioeconomic factors and history of mental disorder in the parents or siblings seemed to confound the result to some extent (adjusted relative risk: 1.9; 95% confidence interval: 1.3-2.8). Adjustment for parental age or exclusion of children with low birth weight (<2500 g), preterm delivery (<37 weeks completed gestation), and Apgar scores <7 at 5 minutes revealed no changes in the results. Also, excluding children with conduct disorders or comorbid disorders revealed no change in the results. CONCLUSIONS: Our results showed an increased risk for hyperkinetic disorder in children of mothers who smoked during pregnancy. This could not be explained by newborn characteristics, parental socioeconomic status, family history of psychiatric hospitalizations or contact as outpatients, conduct disorders, or comorbidity.

Attention Deficit Disorder with Hyperactivity↗
PubMed2005

Prenatal exposure to cigarettes, alcohol, and coffee and the risk for febrile seizures.

OBJECTIVE: Febrile seizure is a common type of seizure in childhood, probably caused by both genetic and early environmental factors. Little is known about the effect of environmental factors that operate in prenatal life, although the fetal brain may be particular vulnerable as a result of extensive brain growth and differentiation in this period. We evaluated the association between prenatal exposure to cigarettes, alcohol, and coffee and the risk for febrile seizures in 2 population-based birth cohorts. METHODS: The Aarhus Birth Cohort consisted of 25,196 children of mothers who were scheduled to deliver at Aarhus University Hospital (1989-1996). The Aalborg-Odense cohort consisted of 10,400 children of women who attended antenatal care in Odense or Aalborg (1984-1987). Both cohorts were linked with the Danish National Hospital Register and followed until December 1998 with a complete follow-up. We extracted from medical records additional information on febrile seizures in children in the Aarhus Birth Cohort who were born between 1989 and 1992. RESULTS: We found a slightly increased risk for febrile seizures in children who were exposed to 10 or more cigarettes per day in the Aarhus Birth Cohort, but the corresponding association was weak in the Aalborg-Odense cohort. We found no association between maternal alcohol and coffee consumption and the risk for febrile seizures. The results were similar for simple and complex febrile seizures. CONCLUSIONS: Our data suggest that prenatal exposure to low to moderate levels of alcohol and coffee has no impact on the risk for febrile seizures, whereas a modest smoking effect cannot be ruled out.

Alcohol Drinking↗
PubMed2004

Alcohol consumption at the time of conception and spontaneous abortion.

The authors studied the association between female and male alcohol intakes at the time of conception and the risk of spontaneous abortion, including early pregnancy loss detected by urinary human chorionic gonadotropin. After a nationwide mailing to about 50,000 members of four trade unions in Denmark in 1992-1994, 430 couples without previous pregnancy attempts were enrolled when birth control was discontinued, and they were followed until a clinically recognized pregnancy or for six menstrual cycles. Alcohol intake and potential confounding factors were reported in monthly questionnaires. Women collected morning urine for 10 days from the first day of vaginal bleeding in each cycle. The authors detected 186 pregnancies: 131 resulted in childbirth, and 55 resulted in spontaneous abortion (34 detected by urinary human chorionic gonadotropin). Depending on the intake in the cycle of conception and the adjustment factors, female alcohol intake was associated with 2-3 times the adjusted risk of spontaneous abortion compared with no intake, and male alcohol intake was associated with 2-5 times the adjusted risk. Only the adjusted relative risks for 10 or more drinks/week compared with no intake were statistically significant. Both male and female alcohol intakes during the week of conception increased the risk of early pregnancy loss.

Abortion, Spontaneous↗
PubMed2004

Reproductive effects of male psychologic stress.

OBJECTIVES: Male psychologic stress can affect semen quality and couple fecundability. METHODS: We conducted a prospective study of 430 Danish couples who were trying to become pregnant for the first time. In each menstrual cycle, both partners filled out a 12-item version of the General Health Questionnaire (GHQ-12), an assessment of psychologic stress. A blood sample was drawn from both partners. The men collected a semen sample at enrollment and each month during follow up. RESULTS: Semen quality was not related to the man's GHQ score in either within-subject analyses or between-subject analyses. There were no consistent associations between stress and serum concentration of luteinizing hormone, follicle-stimulating hormone, inhibin B, testosterone, or estradiol. The pregnancy rate was 14% in cycles with an absolute GHQ-12 score in the highest quartile, compared with 18% in low-stress cycles. Odds of pregnancy decreased moderately with increasing score. The effect was confined to 77 men with a sperm density below 20 million/mL (adjusted odds ratio = 0.06; 95% confidence interval = 1.01-0.58 for highest distressed quartile vs. lowest distressed quartile in this low sperm density group). In within-subject analyses, cycle-specific changes in male stress did not change the odds of pregnancy. High absolute score was associated with a lower frequency of sexual intercourse, but adjustment for frequency had little effect. CONCLUSION: The effect of a man's daily life psychologic stress on his semen quality is small or nonexistent. Our results indicate an effect of stress only on fecundability, and this only among men with low sperm concentration.

Adult↗
PubMed2004

Job strain and male fertility.

BACKGROUND: Job strain, defined as high job demands and low job control, has not previously been explored as a possible determinant of male fertility. We collected prospective data on job strain among men, and describe the associations with semen quality and probability of conceiving a clinical pregnancy during a menstrual cycle. METHODS: Danish couples (N = 399) who were trying to become pregnant for the first time were followed for up to 6 menstrual periods. All men collected semen samples, and a blood sample was drawn from both partners. Job demand and job control were measured by a self-administered questionnaire at entry, and in each cycle the participants recorded changes in job control or job demand during the previous 30 days. RESULTS: In adjusted analyses, no associations were found between any semen characteristic or sexual hormones and any job strain variable. The odds for pregnancy were not associated with job strain. CONCLUSIONS: Psychologic job strain encountered in normal jobs in Denmark does not seem to affect male reproductive function.

Adult↗