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Biomedical subjects

T B Henriksen

Publications and source records attributed to T B Henriksen.

At least 19 recordsLinked to original sources
PubMed2006

A longitudinal study of serum cobalamins and its binding proteins in lactating women.

OBJECTIVE: To examine longitudinal changes in serum cobalamins, transcobalamin (TC) and haptocorrin (HC) during lactation and to investigate the influence of vitamin B12 supplementation on these parameters. DESIGN: A 9-month follow-up study. SUBJECTS AND METHODS: Lactating mothers (N=89) including 23 supplemented with vitamin B12 (1-18 microg/daily), 41 partly supplemented and 25 not supplemented. Blood samples collected 3 weeks (baseline) and 4 and 9 months post-partum were analysed for cobalamins, TC and HC. Both the total concentration and the cobalamin-saturated form (holo) of TC and HC were analysed. RESULTS: No significant differences were observed in serum cobalamins or its binding proteins related to supplementation with vitamin B12 or the duration of lactation. Serum cobalamins remained unchanged from 3 weeks to 9 months post-partum. Total TC (holoTC) (median+/-s.e. pmol/l) decreased between 3 weeks (710+/-23 (85+/-12)) and 9 months (602+/-21 (76+/-11)) (P<0.0001 (P=0.0002)), whereas total HC (holoHC) increased from (422+/-11 (300+/-9)) at 4 months to (455+/-13 (317+/-10)) to 9 months post-partum (P<0.0001 (P<0.0001)). CONCLUSION: We report a decrease in TC and an increase in HC during a 9-month period post-partum. No differences were observed between the vitamin B12-supplemented and the unsupplemented groups. Thus, supplementation with vitamin B12 has no impact on the circulating level of serum cobalamins or its binding proteins in a Danish population of lactating mothers.

Adult↗
PubMed2006

Gestational age, birth weight, and the risk of hyperkinetic disorder.

AIMS: To study the association between gestational age and birth weight and the risk of clinically verified hyperkinetic disorder. METHODS: Nested case-control study of 834 cases and 20 100 controls with incidence density sampling. RESULTS: Compared with children born at term, children born with gestational ages of 34-36 completed weeks had a 70% increased risk of hyperkinetic disorder (rate ratio (RR) 1.7, 95% confidence interval (CI) 1.2 to 2.5). Children with gestational ages below 34 completed weeks had an almost threefold increased risk (RR 2.7, 95% CI 1.8 to 4.1). Children born at term with birth weights of 1500-2499 g had a 90% increased risk of hyperkinetic disorder (RR 1.9, 95% CI 1.2 to 2.9), and children with birth weights of 2500-2999 g had a 50% increased risk (RR 1.5, 95% CI 1.2 to 1.8) compared with children born at term with birth weights above 2999 g. The results were adjusted for socioeconomic status of the parents, family history of psychiatric disorders, conduct disorders, comorbidity, and maternal smoking during pregnancy. Results related to birth weight were unchanged after adjusting for differences in gestational age. CONCLUSIONS: Children born preterm, also close to term, and children born at term with low birth weights (1500-2499 g) have an increased risk of clinically verified hyperkinetic disorder. These findings have important public health perspectives because the majority of preterm babies are born close to term.

Adolescent↗
PubMed2006

Postpartum vitamin D insufficiency and secondary hyperparathyroidism in healthy Danish women.

OBJECTIVE: To examine vitamin D status and parathyroid function in normal Danish women postpartum. DESIGN: Three cross-sectional measures during follow-up of 89 women postpartum. SUBJECTS AND INTERVENTION: We assessed vitamin D status by measuring plasma 25-hydroxyvitamin D (P-25OHD) and the degree of secondary hyperparathyroidism by measuring plasma parathyroid hormone (P-PTH) in 89 Caucasian women at three consecutive visits: (mean (range)) 23 (10-37) days (spring), 117 (95-140) days (late summer) and 274 (254-323) days (winter) postpartum. RESULTS: P-25OHD showed seasonal variations with higher values in late summer than in the other periods (P < 0.001). At the first visit, 65% received vitamin D supplements. At the following visits, almost 50% were supplemented. Vitamin D insufficiency (P-25OHD < 50 nmol/l) occurred more often during winter (28%) than in spring (14%) (Fisher's exact test, P = 0.02) or late summer (7%) (P = 0.0001). Irrespective of season, vitamin D insufficiency occurred most frequent in women who did not take vitamin D supplements (Fisher's exact test, P < 0.02). Frank vitamin D deficiency (P-25OHD < 25 nmol/l) was observed during winter in 6%. At all three periods, P-25OHD correlated inversely with P-PTH indicating secondary hyperparathyroidism at deficient vitamin D status. During spring, late summer and winter three, one and four females, respectively, had elevated plasma PTH. CONCLUSION: Vitamin D insufficiency with secondary hyperparathyroidism is a frequent finding in healthy Danish women postpartum and especially during winter. Vitamin D supplements reduced the risk of vitamin D insufficiency, especially during winter. Our results support the importance of increased alertness regarding information of pregnant and lactating women about vitamin D supplements. Furthermore, it has to be studied whether the present recommendations of an intake of 5-10 microg vitamin D/day are sufficient, especially during winter months.

Adult↗
PubMed2006

Folate and vitamin B12 in relation to lactation: a 9-month postpartum follow-up study.

OBJECTIVE: To investigate the relation between lactation and markers of folate and vitamin B12 (B12) deficiency in women with and without vitamin supplementation. DESIGN: A 9-month follow-up study. SUBJECTS AND METHODS: Blood samples from 91 women, who gave birth to a single healthy child, were collected 3 weeks, 4 and 9 months postpartum and analysed for circulating level of homocysteine (tHcy), methylmalonic acid (MMA), folate and B12. The participants were categorized as exclusively, partly or not breast-feeding dependent on the degree of lactation 4 months postpartum. During follow-up, lifestyle factors were recorded by structured interviews. RESULTS: Among 72 exclusively breast-feeding women, the median (10-90% percentile) tHcy was 5.8 (3.1-8.3) micromol/l 3 weeks postpartum, 6.1 (4.1-10.3) micromol/l 4 months postpartum and 5.3 (3.6-8.7) micromol/I 9 months postpartum. At 9 months postpartum, none of the women breast-fed exclusively. No significant change occurred in the concentration of B12 and folate. Exclusively breast-feeding women without vitamin supplementation had higher median tHcy than supplemented exclusively breast-feeding women 4 and 9 months postpartum (7.0 vs 5.4 micromol/l (P < 0.001) and 5.8 vs 4.5 micromol/l (P = 0.003), respectively). Six women had increased (>15 micromol/l) tHcy; four of these were unsupplemented and exclusively breast-feeding. CONCLUSION: We found no overall indication of depletion of the folate and B12 stores during the lactation period in this population. However, folate-supplemented women had lower tHcy and higher folate levels, suggesting a beneficial effect of supplementation with folate throughout lactation.

Adult↗
PubMed2005

Stress and salivary cortisol during pregnancy.

The purpose of this study was to determine whether exposure to stressful life events was associated with changes in levels of circulating cortisol during pregnancy in a population of 603 pregnant women. The participating pregnant women filled out a questionnaire and collected a morning and evening sample of saliva in early pregnancy (median 14th gestational week) and in late pregnancy (median and 30th gestational week). They were asked to report the number of life events experienced during first and second trimester, respectively, and were asked to rate the intensity of the experienced events. Complications related to the pregnancy such as vaginal bleeding and suspected growth retardation were registered and the women were asked about concerns about their pregnancy. The salivary samples were analyzed for cortisol and the levels were higher in late than in early pregnancy. In late pregnancy women exposed to more than one life event or were concerned about pregnancy complications during second trimester had a higher evening cortisol level, whereas morning values were unaffected. After adjustment for smoking women who experienced more than one very stressful life event had 27% higher evening cortisol concentrations (95% confidence intervals: 1-59%). Women with worries about pregnancy complications had 27% (95% confidence intervals: 2-57%) higher levels. In early pregnancy women reporting stressful life events did not have higher evening cortisol levels, but tended to have a blunted morning HPA response. In conclusion, we found differences in the associations between chronic stress in early and late pregnancy and cortisol levels indicating that the response to chronic stress is dependent on the stage of the pregnancy.

Adult↗
PubMed2003

Umbilical cord mannan-binding lectin and infections in early childhood.

To investigate whether mannan-binding lectin (MBL) in umbilical cord blood (UCB) is associated with the incidence rate of hospitalizations for infections during early childhood. A follow-up study from birth to 31 months of age, with endpoint data from the Danish National Hospital Discharge Registry. The concentration of MBL and immunoglobulin A (IgA) in UCB was measured in a time-resolved immunofluorometric assay. Information on possible confounding factors was obtained from questionnaires completed by mothers during their pregnancy, and characteristics of the child at birth were registered by a midwife on a structured coding sheet. A total of 2104 infants born in the period between 1 February 1990 and 25 May 1991 to mothers living in the municipality of Aarhus. Concentration of MBL and IgA in UCB, gestational age, birth weight, number of siblings less than 3 years old, mother's smoking habits, alcohol and coffee consumption, educational and marital status and previous spontaneous abortions and stillbirths. Of 2104 children, 626 were hospitalized at least once, and 346 of these were hospitalized with infection. The hazard ratio (HR) of hospitalization with infections in children with low levels of MBL (<120 ng/ml) was 1.4 (95% confidence interval (CI), 1.0-1.8), which was similar to our findings on hospitalization because of other diseases. The HR of hospitalization for viral infections was 2.8 (CI, 1.3-5.9). Low levels of MBL in UCB were associated with hospitalization in general and particularly with hospitalization for viral infections.

Adult↗
PubMed2003

Pre-eclampsia and febrile convulsions.

An association between pre-eclampsia and febrile convulsions has been reported, but the association may not be causal. We compared the risk of febrile convulsions in 14 974 children who had been exposed to pre-eclampsia in fetal life with that of 39 210 unexposed children. Children exposed to pre-eclampsia had a slightly increased risk of febrile convulsions, but the association was apparently caused by a shorter gestation in pre-eclamptic women.

Child, Preschool↗
PubMed2002

Febrile convulsions and sudden infant death syndrome.

It has been suggested that sudden infant death syndrome (SIDS) and febrile convulsions are related aetiologically. We compared the risk of SIDS in 9877 siblings of children who had had febrile convulsions with that of 20 177 siblings of children who had never had febrile convulsions. We found no support for the shared susceptibility hypothesis.

Child, Preschool↗
PubMed2001

Exposure to tobacco smoke in utero and the risk of stillbirth and death in the first year of life.

The authors examined the association between exposure to tobacco smoke in utero and the risk of stillbirth and infant death in a cohort of 25,102 singleton children of pregnant women scheduled to deliver at Aarhus University Hospital, Aarhus, Denmark, from September 1989 to August 1996. Exposure to tobacco smoke in utero was associated with an increased risk of stillbirth (odds ratio = 2.0, 95% confidence interval: 1.4, 2.9), and infant mortality was almost doubled in children born to women who had smoked during pregnancy compared with children of nonsmokers (odds ratio = 1.8, 95% confidence interval: 1.3, 2.6). Among children of women who stopped smoking during the first trimester, stillbirth and infant mortality was comparable with that in children of women who had been nonsmokers from the beginning of pregnancy. Conclusions were not changed after adjustment in a logistic regression model for the sex of the child; parity; or maternal age, height, weight, marital status, years of education, occupational status, and alcohol and caffeine intake during pregnancy. Approximately 25% of all stillbirths and 20% of all infant deaths in a population with 30% pregnant smokers could be avoided if all pregnant smokers stopped smoking by the sixteenth week of gestation.

Denmark↗
PubMed2001

Obstetric complications in women with schizophrenia.

It is not known whether schizophrenic women have increased incidence of complications during pregnancy and delivery. Data from the Danish Medical Birth Register were used to compare 2212 births to 1537 schizophrenic women in Denmark with a random sample of all deliveries in Denmark during 1973-1993 (122931 births to 72742 women). The schizophrenic women had fewer antenatal care visits. They were at lower risk of pre-eclampsia, but tended to have lower Apgar scores. There were no other differences in the incidence of specific complications such as placenta previa, placental abruption, and abnormal fetal presentation. Schizophrenic women were at increased risk of interventions such as Cesarean section, vaginal assisted delivery, amniotomy, and pharmacological stimulation of labor. There were no important differences between the deliveries to schizophrenic women who gave birth before and after their first admission to a psychiatric department. These results show no evidence that schizophrenic women have a greater frequency of specific obstetric complications than non-schizophrenic women. Nevertheless, they are at increased risk for interventions during delivery.

Adult↗
PubMed2001

Congenital malformations, stillbirths, and infant deaths among children of women with schizophrenia.

BACKGROUND: Women with schizophrenia have increased exposure to risk factors for congenital malformations, stillbirths, and infant deaths among their children. However, the occurrence of these outcomes is unknown. METHODS: The risks of stillbirth and infant death among 2230 children of women with schizophrenia were compared with the risks among 123 544 children in the general population. The risk of congenital malformations among 746 children of women with schizophrenia were compared with the risk among 56 106 children in the general population. The year of birth, the sex of the child, the mother's age, and parity were included in the analyses as potential confounders. We had no information about socioeconomic status, smoking status, substance abuse, or psychotropic medication use. RESULTS: Children of women with schizophrenia had increased risk of postneonatal death (relative risk [RR], 2.76; 95% confidence interval [CI], 1.67-4.56). This was largely explained by an increased risk of sudden infant death syndrome (RR, 5.23; 95% CI, 2.82-9.69). There was no statistically significant increased risk of stillbirth (RR, 1.51; 95% CI, 0.94-2.40) or neonatal death (RR, 1.26; CI, 0.77-2.06). Children of women with schizophrenia had a marginally statistically significant increase in the risk of congenital malformations (RR, 1.70; 95% CI, 1.04-2.77). CONCLUSIONS: Children of women with schizophrenia have a considerable increased risk of death caused by sudden infant death syndrome. However, the results should be interpreted in the light of failure to adjust for socioeconomic status, substance abuse, smoking status, and psychotropic medication use.

Adult↗
PubMed2001

Maternal smoking and gestational age in twin pregnancies.

BACKGROUND: A twin pregnancy imposes greater demands on maternal physiology and smoking may thus be associated theoretically with a greater risk of preterm delivery than in singleton pregnancies. POPULATION AND METHODS: From 1989 to 1996 all women who booked for antenatal care at the Department of Gynecology and Obstetrics, Aarhus University Hospital, Denmark were asked to fill in two questionnaires. Apart from smoking habits, these questionnaires provided information on medical and obstetric history together with information on sociodemographic and other lifestyle variables. Gestational age at delivery was calculated from ultrasonographically determined fetal biparietal diameter and information about the last menstrual period. Only women carrying twins were included in the present study (n=401). RESULTS: Mean gestational age was 5 days (95% CI 1-9 days) shorter among smokers compared with non-smokers. Among non-smokers mean gestational age was 261 days (+/-18), among women who smoked 1-9 and 10+ cigarettes per day 257 days (+/-23) and 255 days (+/-20), respectively. The overall risk of preterm delivery (< 37 weeks) and delivery before 34 completed weeks was 1.3 (95% CI 0.9-2.2) and 1.4 (95% CI 0.8-2.4), respectively. Primiparous women had shorter gestational age than did multiparous women. Still, among primiparous as well as among multiparous women gestational age decreased with smoking. Adjustment for maternal age, height and prepregnancy weight, alcohol and caffeine intake, marital status, education, occupational status, preterm birth in previous pregnancies, and in vitro fertilization in the present pregnancy did not change the results. CONCLUSIONS: Smoking has a substantial effect on mean gestational age in twin pregnancies, and a dose response like relationship is present.

Adolescent↗
PubMed2001

An increasing proportion of infants weigh more than 4000 grams at birth.

BACKGROUND: To investigate how mean birthweight has changed in the past decade, and to describe changes in the proportion of infants with a birthweight above 4000 grams (g). METHODS: We analyzed data on 43,561 singleton infants born between 1990 and 1999 at Aarhus University Hospital, Denmark. Information on birthweight, gestational age, stillbirths, malformations, mode of delivery, prelabor intervention, and maternal diabetes was obtained from birth registration forms. RESULTS: For all infants mean birthweight increased by 45 g (95% CI: 20-70 g) from 3474 g in 1990 to 3519 g in 1999. For infants born at term the mean increase was 62 g (95% CI: 41-83 g). During the same period the percentage of infants born with a birthweight above 4000 g increased from 16.7% in 1990 to 20.0% in 1999 (p<0.05). Simultaneously we found a decrease in gestational age and an increase in the frequency of induction of labor. There was a statistically significantly higher risk of giving birth to an infant with a birthweight above 4000 g throughout the decade, when gestational age and prelabor intervention was taken into account. CONCLUSIONS: In Denmark mean birthweight has risen during the past decade independently of gestational age and prelabor intervention. Simultaneously the risk of having a baby with a birthweight above 4000 g has increased. Further studies on potential risk factors for birth of large infants are needed.

Birth Weight↗
PubMed2001

Smoking during pregnancy and infantile colic.

OBJECTIVE: To evaluate the association between maternal smoking during pregnancy and infantile colic (IC). METHODS: A follow-up study of singleton infants delivered by Danish mothers at the Aarhus University Hospital from May 1991 to February 1992 and still living in the municipality of Aarhus at the age of 8 months was conducted. A total of 1820 mothers and their infants were included. Self-administered questionnaires were used to collect data on smoking, other lifestyle factors, and sociodemographic variables at 16 and 30 weeks of gestation and 8 months postpartum. IC was defined in the 8-month questionnaire and based on Wessel's criteria, except that we used only the crying criterion. RESULTS: IC was seen in 10.8% of all infants. We observed a twofold increased risk of IC among infants whose mothers smoked 15 or more cigarettes per day during their pregnancy(relative risk: 2.1; 95% confidence interval: 1.4-3.2) or in the postpartum period (relative risk: 2.0; 95% confidence interval: 1.3-3.1). Women who smoked continuously during pregnancy and the postpartum period had a relative risk of 1.5 (95% confidence interval: 1.1-2.0) of having a infant with IC compared with women who did not smoke during this period. Adjustment for maternal age, parity, marital status, alcohol intake, birth weight, gestational age, breastfeeding, caffeine intake postpartum, and paternal smoking did not change the effect measures. CONCLUSION: The results indicate that maternal smoking during pregnancy may increase the risk of IC.

Adolescent↗
PubMed2000

[Stress and fertility. A follow-up study among couples planning the first pregnancy].

Mental distress has often been suggested as a cause of unexplained infertility. However, the causal direction may well be from infertility to distress, and prospective data are needed. We therefore followed 393 couples, who were planning their first pregnancy, with prospective collection of information on distress from termination of birth control until pregnancy for a maximum of six menstrual cycles. The analyses included 1,475 menstrual cycles, and mental distress was measured in each cycle by the General Health Questionnaire (GHQ). Urine samples from each period of vaginal bleeding were analyzed for human chorionic gonadotrophic hormone, indicating early embryonal loss. We found that for cycles with the highest distress score (GHQ score above the 80 percentile) the probability of conception per cycle was 12.8% compared to 16.5% in other cycles (adjusted OR 0.6; 95% CI 0.4-1.0). The effect of distress was almost exclusively found among women with long menstrual cycles (OR 0.1; 95% CI 0.01-0.4 and OR 0.9; 0.5-1.4 for women with cycles > or = 35 and < 35 days, respectively). An increased incidence of early embryonal loss was also found among highly distressed women with long cycles, but was based on a small number of observations. It is concluded that psychological distress may be a risk factor for reduced fertility in women with long menstrual cycles.

Adult↗
PubMed2000

Nicotine patches for pregnant smokers: a randomized controlled study.

OBJECTIVE: To assess the effect of nicotine patches on continine-validated smoking cessation in pregnant women and the effect of nicotine on birth weight and preterm delivery. METHODS: Pregnant women who smoked ten or more cigarettes after the first trimester (N = 250) were randomly assigned to receive nicotine patches (n = 124) or placebo patches (n = 126). Women randomized to nicotine were treated with 15-mg patches (16 hours/day) for 8 weeks, and 10-mg patches (16 hours/day) for 3 weeks. RESULTS: Overall, 26% stopped smoking and 14% were nonsmokers 1 year after delivery. There was no difference between nicotine and placebo groups. At the end of the intervention, the mean value of cotinine in saliva in women assigned to nicotine was 120 ng/mL and placebo 153 ng/mL (mean difference -33; 95% CI -72, 6 ng/mL). Mean birth weight difference was 186 g (95% CI 35, 336 g) higher in the nicotine than placebo group, and there was an insignificantly lower rate of low birth weight (under 2500 g) in the former group. There was no difference in the rate of preterm delivery between the two groups. CONCLUSION: Nicotine patches had no influence on smoking cessation during pregnancy, although they might increase birth weight in comparison with placebo.

Administration, Cutaneous↗
PubMed2000

Spontaneous abortion and physical strain around implantation: a follow-up study of first-pregnancy planners.

Existing studies of physical strain and spontaneous abortion are mainly retrospective or based only on pregnancies that have survived the first trimester. Furthermore, almost all studies have relied on averaged measures of physical strain, which tend to blur an effect if peak values during short time periods are the relevant measure. We followed a cohort of first pregnancy planners from termination of birth control until pregnancy for a maximum of six menstrual cycles. The analyses include 181 pregnancies, of which 32 were subclinical pregnancies detected by hCG analysis only. During early pregnancy the women recorded physical strain prospectively in a structured diary. Physical strain around the time of implantation was associated with later spontaneous abortion. The adjusted risk ratio for women who reported physical strain higher than average at day 6 to 9 after the estimated date of ovulation was 2.5 (95% CI = 1.3-4.6).

Abortion, Spontaneous↗