JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Maternal Bereavement and Cryptorchidism in Offspring.
Epidemiology
PUBLISHED: 10-21-2014
Show Abstract
Hide Abstract
Cryptorchidism (undescended testis) is a common anomaly with largely unexplained etiology. Animal studies have suggested maternal emotional stress as a potential risk factor, but this has not been studied in humans. We aimed to investigate whether maternal bereavement due to the death of a close relative in the antenatal period increases the occurrence of cryptorchidism in the offspring.
Related JoVE Video
Epidemiologic methods for investigating male fecundity.
Asian J. Androl.
PUBLISHED: 09-03-2014
Show Abstract
Hide Abstract
Fertility is a couple concept that has been measured since the beginning of demography, and male fecundity (his biological capacity to reproduce) is a component of the fertility rate. Unfortunately, we have no way of measuring the male component directly, although several indirect markers can be used. Population registers can be used to monitor the proportion of childless couples, couples who receive donor semen, trends in dizygotic twinning, and infertility diagnoses. Studies using time-to-pregnancy (TTP) may identify couple subfecundity, and TTP data will correlate with sperm quality and quantity as well as sexual activity and a number of other conditions. Having exposure data available for couples with a fecund female partner would make TTP studies of interest in identifying exposures that may affect male fecundity. Biological indicators such as sperm quality and quantity isolate the male component of fertility, and semen data therefore remain an important source of information for research. Unfortunately, often over half of those invited to provide a sperm sample will refuse, and the study is then subject to a selection that may introduce bias. Because the most important time windows for exposures that impair semen production could be early fetal life, puberty, and the time of ejaculation; longitudinal data over decades of time are required. The ongoing monitoring of semen quality and quantity should continue, and surveys monitoring fertility and waiting TTP should also be designed.
Related JoVE Video
Breast cancer risk after exposure to perfluorinated compounds in Danish women: a case-control study nested in the Danish National Birth Cohort.
Cancer Causes Control
PUBLISHED: 08-23-2014
Show Abstract
Hide Abstract
Animal studies have indicated that perfluoroalkylated substances (PFAS) increase mammary fibroadenomas. A recent case-control study in Greenlandic Inuit women showed an association between the PFAS serum levels and breast cancer (BC) risk. The present study evaluates the association between serum levels of PFAS in pregnant Danish women and the risk of premenopausal BC during a follow-up period of 10-15 years using prospectively collected exposure data during the pregnancy.
Related JoVE Video
Prenatal exposure to perfluoroalkyl substances and the risk of congenital cerebral palsy in children.
Am. J. Epidemiol.
PUBLISHED: 08-19-2014
Show Abstract
Hide Abstract
Perfluoroalkyl substances (PFASs) are persistent pollutants and endocrine disruptors that may affect fetal brain development. We investigated whether prenatal exposure to PFASs increases the risk of congenital cerebral palsy (CP). The source population for this study includes 83,389 liveborn singletons and mothers enrolled in the Danish National Birth Cohort during 1996-2002. We identified 156 CP cases by linking the cohort to the Danish National Cerebral Palsy Register, and we randomly selected 550 controls using a case-cohort design. We measured 16 PFASs in maternal plasma collected in early or midpregnancy, and 6 PFASs were quantifiable in more than 90% of the samples. We found a higher risk of CP in boys with higher maternal PFAS levels; per 1-unit (natural-log ng/mL) increase, the risk ratios were 1.7 (95% confidence interval: 1.0, 2.8) for perfluorooctane sulfonate and 2.1 (95% confidence interval: 1.2, 3.6) for perfluorooctanoic acid. We also observed a dose-response pattern of CP risk in boys per quartile of maternal level of perfluorooctane sulfonate and perfluorooctanoic acid (P for trend < 0.01). PFASs were associated with both unilateral and bilateral spastic CP subphenotypes. No association between PFASs and CP was found in girls. Prenatal exposures to PFASs may increase the risk of CP in boys, but the finding is novel and replication is needed.
Related JoVE Video
Trimethoprim use before pregnancy and risk of congenital malformation: reanalyzed using a case-crossover design and a case-time-control design.
Pharmacoepidemiol Drug Saf
PUBLISHED: 08-11-2014
Show Abstract
Hide Abstract
Studies on the safety of drugs used during pregnancy are necessary and important but prone to bias. Using cases as their own controls can reduce bias. We used a case-crossover design and a case-time-control design to estimate the risk of congenital malformation (CM) for children born to mothers who redeemed a trimethoprim prescription shortly before pregnancy.
Related JoVE Video
[Epidemiological methods for evaluating screening programmes.]
Ugeskr. Laeg.
PUBLISHED: 08-07-2014
Show Abstract
Hide Abstract
The effect of screening programmes must be estimated before the programmes are implemented. Usually, the evaluation includes randomized trials if possible but even a large randomized trial will have limitations and need not estimate effects properly under routine conditions.
Related JoVE Video
Parental smoking during pregnancy and ADHD in children: the Danish national birth cohort.
Pediatrics
PUBLISHED: 07-23-2014
Show Abstract
Hide Abstract
Prenatal maternal smoking has been associated with attention-deficit/hyperactivity disorder (ADHD) in children, but the causal nature of this association is still under scrutiny. We examined the association with maternal smoking and nicotine replacement use during pregnancy, using association with paternal smoking as a marker of potential genetic or social confounding.
Related JoVE Video
Related JoVE Video
Mortality after parental death in childhood: a nationwide cohort study from three Nordic countries.
PLoS Med.
PUBLISHED: 07-01-2014
Show Abstract
Hide Abstract
Bereavement by spousal death and child death in adulthood has been shown to lead to an increased risk of mortality. Maternal death in infancy or parental death in early childhood may have an impact on mortality but evidence has been limited to short-term or selected causes of death. Little is known about long-term or cause-specific mortality after parental death in childhood.
Related JoVE Video
Severity of birth defects after propylthiouracil exposure in early pregnancy.
Thyroid
PUBLISHED: 06-25-2014
Show Abstract
Hide Abstract
Propylthiouracil (PTU) used in the treatment of maternal hyperthyroidism in early pregnancy may be associated with a higher prevalence of birth defects in the face and neck region and in the urinary system but the severity of these complications remains to be elucidated.
Related JoVE Video
In utero exposure to alcohol and puberty in boys: a pregnancy cohort study.
BMJ Open
PUBLISHED: 06-12-2014
Show Abstract
Hide Abstract
Epidemiological studies have raised concerns about the reproductive consequences of in utero exposure to alcohol. Maternal lifestyle factors have been associated with altered pubertal development, but the impact of prenatal alcohol exposure on male puberty is unknown. Thus, the objective was to explore whether prenatal alcohol exposure alters pubertal development in boys.
Related JoVE Video
Psychiatric disorders following fetal death: a population-based cohort study.
BMJ Open
PUBLISHED: 06-08-2014
Show Abstract
Hide Abstract
Women have increased risks of severe mental disorders after childbirth and death of a child, but it remains unclear whether this association also applies to fetal loss and, if so, to which extent. We studied the risk of any inpatient or outpatient psychiatric treatment during the time period from 12?months before to 12?months after fetal death.
Related JoVE Video
Fetal growth and preterm birth in children exposed to maternal or paternal rheumatoid arthritis. A nationwide cohort study.
PUBLISHED: 04-02-2014
Show Abstract
Hide Abstract
Objective. To assess indicators of fetal growth and risk of preterm birth in children of parents with rheumatoid arthritis (RA). Methods. Through linkage of Danish national registries we identified all children born in Denmark between 1977 and 2008. We used general linear regression models to estimate mean differences in indicators of fetal growth among children having a parent with RA compared to unexposed children. Odds ratios of preterm birth were calculated by a logistic regression model. Results. Of the 1,917,723 children included, a total of 13,556 children were exposed to maternal RA or pre-clinical RA. Children exposed to maternal RA (2,101) had approximately similar length, head and abdominal circumference at birth, compared with children of mothers without RA. Birth weight was 87 gram lower (-87.04 g; 95% CI, -111.23;-62.84) and placenta weight was 14 gram lower (-13.45 g; 95% CI, -21.46;-5.43). Rather similar results were found in children exposed to pre-clinical RA (11,455). Compared with unexposed children a higher risk of preterm birth was found in children exposed to maternal RA and pre-clinical RA respectively (OR, 1.48; 95% CI,1.20;1.84 and OR, 1.32; 95% CI,1.07;1.64). No associations were found with paternal RA. Conclusion. Children exposed to either maternal RA or pre-clinical RA are more often born preterm. However, indicators of fetal growth measured at birth were only slightly lower than in unexposed children. © 2014 American College of Rheumatology.
Related JoVE Video
Acetaminophen use during pregnancy, behavioral problems, and hyperkinetic disorders.
JAMA Pediatr
PUBLISHED: 02-26-2014
Show Abstract
Hide Abstract
Acetaminophen (paracetamol) is the most commonly used medication for pain and fever during pregnancy in many countries. Research data suggest that acetaminophen is a hormone disruptor, and abnormal hormonal exposures in pregnancy may influence fetal brain development.
Related JoVE Video
Birth weight, gestational age, fetal growth and childhood asthma hospitalization.
Allergy Asthma Clin Immunol
PUBLISHED: 02-21-2014
Show Abstract
Hide Abstract
Childhood asthma may have a fetal origin through fetal growth and development of the immunocompetence or respiratory organs.
Related JoVE Video
Psychiatric disease in late adolescence and young adulthood. Foetal programming by maternal hypothyroidism?
Clin. Endocrinol. (Oxf)
PUBLISHED: 01-09-2014
Show Abstract
Hide Abstract
Lack of maternal thyroid hormones during foetal brain development may lead to structural abnormalities in the brain. We hypothesized that maternal hypothyroidism during the pregnancy could programme the foetus to development of psychiatric disease later in life.
Related JoVE Video
Cancer risks in children with congenital malformations in the nervous and circulatory system-A population based cohort study.
Cancer Epidemiol
PUBLISHED: 01-03-2014
Show Abstract
Hide Abstract
We estimated the age and organ-specific cancer risk for children with a congenital malformation (CM) in the nervous or in the circulatory system.
Related JoVE Video
Prenatal exposure to maternal bereavement and childbirths in the offspring: a population-based cohort study.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The decline in birth rates is a concern in public health. Fertility is partly determined before birth by the intrauterine environment and prenatal exposure to maternal stress could, through hormonal disturbance, play a role. There has been such evidence from animal studies but not from humans. We aimed to examine the association between prenatal stress due to maternal bereavement following the death of a relative and childbirths in the offspring.
Related JoVE Video
Severe maternal stress exposure due to bereavement before, during and after pregnancy and risk of overweight and obesity in young adult men: a Danish National Cohort Study.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Perinatal stress may programme overweight and obesity. We examined whether maternal pre- and post-natal bereavement was associated with overweight and obesity in young men.
Related JoVE Video
Maternal pre-pregnancy BMI and intelligence quotient (IQ) in 5-year-old children: a cohort based study.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
An association between maternal pre-pregnancy BMI and childhood intelligence quotient (IQ) has repeatedly been found but it is unknown if this association is causal or due to confounding caused by genetic or social factors.
Related JoVE Video
In-utero exposure to bereavement and offspring IQ: a Danish national cohort study.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Intelligence is a life-long trait that has strong influences on lifestyle, adult morbidity and life expectancy. Hence, lower cognitive abilities are therefore of public health interest. Our primary aim was to examine if prenatal bereavement measured as exposure to death of a close family member is associated with the intelligence quotient (IQ) scores at 18-years of age of adult Danish males completing a military cognitive screening examination.
Related JoVE Video
Who needs selection bias?
Scand J Work Environ Health
PUBLISHED: 11-28-2013
Show Abstract
Hide Abstract
Present day low participation rates in certain parts of research is concerning. It is not unusual that half (or even more) of those invited to participate in a research project decline the invitation. Many think this will always lead to selection bias regardless of the type of study in question. That is fortunately not the case. Selection bias is a reason for concern in studies that aim to obtain a representative sample concerning risk factors or outcomes. Those who decline participation will often have a higher risk profile (lower social status, smokers etc) and more chronic disorders. Selection bias of the most serious type is related to the specific hypothesis when the hypothesis is known to participants. Being asked to participate in a study on oral contraceptives (OC) and breast cancer, for example, may be more appealing to women with breast cancer who have used OC. Selection is therefore often of concern in case-control studies. Non-response and selection bias is of less concern in follow-up studies where the outcome is not known at the time of recruitment. The reason for limited interest in "representativeness" is that scientific inference addresses a potential cause-effect relation in general, not in a specific population. Whether an established cause-effect relation is present in a specific population with a given effect estimate is a matter of effect measure modification and the distribution of component causes in that population at that given time period. Non-response in a follow-up study is expected to affect the structure of the population and influence the confounder distribution, often by producing less confounding because those with health problems and extreme lifestyle factors are more likely to decline participation. Since these factors may act as confounders, selection may change effect sizes without bias but just because effect sizes are population-specific. One should, however, be aware of a selection bias that would not be present with complete case ascertainment as illustrated in figure 1. Without selection (S), C 3would not cause bias, but S (conditioned upon) will link C 3to E, and establish the backdoor E-C 3-D that can be closed by adjusting for C 3. In a like manner, C 1and C 2have confounding potential because conditioning on S will produce the backdoor paths C 1-C 3-D and C 1-C 2-D. Adjustments for C 2and C 3will be needed. This will happen even in situations where S is not directly linked to D (because D has not occurred at the time of recruitment). Direct selection bias relating S to both E and D is only expected if D can be predicted by study participants (eg, by using the family history of disease occurrence). Selection in a cohort will not in itself lead to selection bias but will often produce a different confounder structure and therefore call for a different strategy when deciding on which confounders to include and how to treat them in the analysis.
Related JoVE Video
Gestational Age, Small for Gestational Age, and Infantile Colic.
Paediatr Perinat Epidemiol
PUBLISHED: 11-21-2013
Show Abstract
Hide Abstract
Preterm and growth restricted infants may have developmental delays and deviations from normal organ function related to the gastrointestinal tract and the central nervous system. Since both organ systems are hypothesised to be involved in the pathogenesis of infantile colic, a condition characterised by excessive crying during the first months of life, impaired fetal growth and preterm birth may be risk factors for infantile colic.
Related JoVE Video
Birth defects after early pregnancy use of antithyroid drugs: a Danish nationwide study.
J. Clin. Endocrinol. Metab.
PUBLISHED: 10-22-2013
Show Abstract
Hide Abstract
Hyperthyroidism in pregnant women should be adequately treated to prevent maternal and fetal complications, but teratogenic effects of antithyroid drug (ATD) treatment have been described. Evidence is still lacking in regard to the safety and choice of ATD in early pregnancy.
Related JoVE Video
Maternal infections during pregnancy and cerebral palsy: a population-based cohort study.
Paediatr Perinat Epidemiol
PUBLISHED: 10-10-2013
Show Abstract
Hide Abstract
Cerebral palsy (CP) is a common motor disability in childhood. We examined the association between maternal infections during pregnancy and the risk of congenital CP in the child.
Related JoVE Video
Asthma during pregnancy and clinical outcomes in offspring: a national cohort study.
Pediatrics
PUBLISHED: 08-05-2013
Show Abstract
Hide Abstract
Maternal asthma is a common pregnancy complication, with adverse short-term effects for the offspring. The objective was to determine whether asthma during pregnancy is a risk factor of offspring diseases.
Related JoVE Video
Complexities of sibling analysis when exposures and outcomes change with time and birth order.
J Expo Sci Environ Epidemiol
PUBLISHED: 07-03-2013
Show Abstract
Hide Abstract
In this study, we demonstrate the complexities of performing a sibling analysis with a re-examination of associations between cell phone exposures and behavioral problems observed previously in the Danish National Birth Cohort. Children (52,680; including 5441 siblings) followed up to age 7 were included. We examined differences in exposures and behavioral problems between siblings and non-siblings and by birth order and birth year. We estimated associations between cell phone exposures and behavioral problems while accounting for the random family effect among siblings. The association of behavioral problems with both prenatal and postnatal exposure differed between siblings (odds ratio (OR): 1.07; 95% confidence interval (CI): 0.69-1.66) and non-siblings (OR: 1.54; 95% CI: 1.36-1.74) and within siblings by birth order; the association was strongest for first-born siblings (OR: 1.72; 95% CI: 0.86-3.42) and negative for later-born siblings (OR: 0.63; 95% CI: 0.31-1.25), which may be because of increases in cell phone use with later birth year. Sibling analysis can be a powerful tool for (partially) accounting for confounding by invariant unmeasured within-family factors, but it cannot account for uncontrolled confounding by varying family-level factors, such as those that vary with time and birth order.Journal of Exposure Science and Environmental Epidemiology advance online publication, 25 September 2013; doi:10.1038/jes.2013.56.
Related JoVE Video
Prenatal exposures to perfluorinated chemicals and anthropometry at 7 years of age.
Am. J. Epidemiol.
PUBLISHED: 07-03-2013
Show Abstract
Hide Abstract
Fetal exposure to the perfluoroalkyl acids, perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA), has been associated with lower birth weight and lower weight and body mass index (weight (kg)/height (m)(2)) in early infancy. It is, however, unclear if exposure to prenatal PFOS and PFOA has a lasting influence on growth. We estimated the associations between the maternal plasma level of PFOS or PFOA and the childrens body mass index, waist circumference, and risk of overweight at 7 years of age. A total of 1,400 women were randomly selected from the Danish National Birth Cohort among those who provided blood samples early in pregnancy and gave birth to liveborn singletons in 1996-2002. Weight and height information at 7 years was available for 811 children. Multiple linear and logistic regression models were used for analyses. Maternal PFOS and PFOA concentrations were overall inversely but nonsignificantly associated with the childrens body mass index, waist circumference, and risk of overweight at 7 years of age. In conclusion, plasma levels of PFOS and PFOA in pregnant women did not seem to have any appreciable influence on their childrens anthropometry at this point in childhood.
Related JoVE Video
Smoking reduces the risk of hypothyroidism and increases the risk of hyperthyroidism: evidence from 450 842 mothers giving birth in Denmark.
Clin. Endocrinol. (Oxf)
PUBLISHED: 05-30-2013
Show Abstract
Hide Abstract
Smoking may influence on the occurrence of thyroid disease, but studies have led to inconsistent results. In Denmark, information on maternal smoking during pregnancy is registered by midwives, and we investigated the association between maternal smoking as reported during pregnancy and the subsequent maternal risk of having hyper- or hypothyroidism diagnosed.
Related JoVE Video
Social conditions for people with Down syndrome: A register-based cohort study in Denmark.
Am. J. Med. Genet. A
PUBLISHED: 05-01-2013
Show Abstract
Hide Abstract
Today, most persons with Down syndrome (DS) survive into middle age, but information on their social conditions as adults is limited. We addressed this knowledge gap using data from national registers in Denmark. We identified a national cohort of 1,998 persons with DS who were born between 1968 and 2007 (1,852 with standard trisomy 21, 80 with Robertsonian translocations and 66 with mosaicism) using the Danish Cytogenetic Register. We followed this cohort from 1980 to 2007. Information on social conditions (education, employment, source of income, marital status, etc.) was obtained by linkages to national registers, including the Integrated Database for Longitudinal Labor Market Research. For those aged 18 and older, more than 80% of persons with DS attended 10 years of primary school, with about 2% completing secondary or post-secondary education. About 4% obtained a full-time job, whereas the remaining mainly received public support from the government. Only a few (1-2%) of persons with DS were married or had a child. No significant differences in these social conditions were seen between males and females. More persons with mosaic DS attended secondary or post-secondary education, had a full-time job, were married, or had a child (18%, 28%, 15%, and 7%, respectively), compared with persons with standard DS (1%, 2%, 1%, and 1%, respectively). These data may provide families with better insight into social conditions and society with a better understanding of the social support needed for persons with DS. © 2013 Wiley Periodicals, Inc.
Related JoVE Video
Prenatal exposure to selective serotonin reuptake inhibitors and childhood overweight at 7 years of age.
Ann Epidemiol
PUBLISHED: 05-01-2013
Show Abstract
Hide Abstract
To investigate a possible association between prenatal selective serotonin reuptake inhibitor (SSRI) exposure and childhood overweight at 7 years of age.
Related JoVE Video
Womens worries in first pregnancy: results from a randomised controlled trial.
Sex Reprod Healthc
PUBLISHED: 04-23-2013
Show Abstract
Hide Abstract
It has been suggested that participation in an antenatal education programme will increase the level of worry in pregnant women. This randomised controlled trial, investigated womens worries in late pregnancy as a secondary outcome depending on their attendance in an antenatal education programme. We found that women attending the education programme reported a lower level of worry in late pregnancy, especially worries related to birth issues, compared to those who did not attend the antenatal education programme.
Related JoVE Video
Psychosocial stress related to the loss of a close relative the year before or during pregnancy and risk of preeclampsia.
Hypertension
PUBLISHED: 04-22-2013
Show Abstract
Hide Abstract
The role of stress in the pathogenesis of preeclampsia has only been investigated in a few studies, and the findings are not conclusive. We analyzed whether maternal bereavement shortly before or during pregnancy is associated with an increased risk of preeclampsia. We conducted a cohort study of singleton births in Denmark during 1978-2008 and in Sweden during 1973-2006 (n=4 122 490) by linking national population-based registers. Mothers were considered exposed to bereavement if they lost a parent, a sibling, a partner, or a child the year before or during pregnancy (n=124 553). The risk of preeclampsia was slightly increased for women who lost a close relative during the 6 months before conception (odds ratio [OR], 1.14; 95% confidence interval [CI], 1.06-1.23) or during the first trimester of pregnancy (OR, 1.15; 95% CI, 1.03-1.29). Exposure during these periods tended to be more closely related to early preeclampsia (delivery before 34 weeks of gestation; OR, 1.37; 95% CI, 1.12-1.67) than to late preeclampsia (OR, 1.13; 95% CI, 1.06-1.20). The strongest association was observed between loss of a child and early preeclampsia when the exposure window was from 6 months before pregnancy until start of second trimester (OR, 4.03; 95% CI, 2.46-6.61). Our results related to timing of exposure suggest that severe stress may influence early placentation. However, the public health implications of our findings are limited in populations with a low prevalence of severe stress exposures.
Related JoVE Video
Maternal thyroid dysfunction and risk of seizure in the child: a Danish nationwide cohort study.
J Pregnancy
PUBLISHED: 04-11-2013
Show Abstract
Hide Abstract
Thyroid hormones are essential for brain development, and maternal thyroid disease may affect child neurocognitive development. Some types of seizures may also depend upon early exposure of the developing central nervous system, and we hypothesized that maternal thyroid dysfunction could increase the risk of seizure in the child. In a Danish population-based study we included 1,699,693 liveborn singletons, and from the Danish National Hospital Register we obtained information on maternal diagnosis of hyper- or hypothyroidism and neonatal seizure, febrile seizure, and epilepsy in the child. Maternal diagnosis of thyroid dysfunction before or after birth of the child was registered in two percent of the singleton births. In adjusted analyses, maternal hyperthyroidism and hypothyroidism first time diagnosed after birth of the child were associated with a significant increased risk of epilepsy in the child. Moreover, hypothyroidism diagnosed after birth of the child was associated with a significant increased risk of neonatal and febrile seizures. No significant association was seen for maternal diagnosis prior to birth of the child. We speculate if some degree of maternal thyroid dysfunction was already present during the pregnancy in mothers diagnosed after birth of the child and if this untreated condition may present a neurodevelopmental risk.
Related JoVE Video
Prenatal maternal bereavement and congenital heart defects in offspring: a registry-based study.
Pediatrics
PUBLISHED: 03-25-2013
Show Abstract
Hide Abstract
It has been suggested that maternal emotional stress during cardiogenesis may be a risk factor for congenital heart defects (CHD). We examined this association using bereavement around the time of conception as an indicator of maternal exposure to stress in a large registry-based study.
Related JoVE Video
Age at menarche and pregnancy-related pelvic pain.
J. Obstet. Gynaecol. Res.
PUBLISHED: 03-17-2013
Show Abstract
Hide Abstract
Menarcheal age is a predictor of several complications related to pregnancy and diseases later in life. We aimed to study if menarcheal age is a risk factor for pregnancy-related pelvic pain.
Related JoVE Video
Congenital cerebral palsy and prenatal exposure to self-reported maternal infections, fever, or smoking.
Am. J. Obstet. Gynecol.
PUBLISHED: 03-03-2013
Show Abstract
Hide Abstract
The objective of the study was to investigate the association between maternal self-reported infections, fever, and smoking in the prenatal period and the subsequent risk for congenital cerebral palsy (CP).
Related JoVE Video
Risk of substance use disorders following prenatal or postnatal exposure to bereavement.
Drug Alcohol Depend
PUBLISHED: 02-12-2013
Show Abstract
Hide Abstract
Substance use disorder (SUD) is associated with major socioeconomic consequences but its etiology is only partly known. The disease predisposition may be established early in life and prenatal stress may play a role. We aimed to examine whether prenatal maternal bereavement, as the indicator of prenatal stress, was associated with an increased risk of SUD in offspring.
Related JoVE Video
Hospitalizations among people with Down syndrome: a nationwide population-based study in Denmark.
Am. J. Med. Genet. A
PUBLISHED: 02-12-2013
Show Abstract
Hide Abstract
Most persons with Down syndrome (DS) now survive to adulthood, but their health care needs beyond childhood are not well described. We followed a national cohort of 3,212 persons with DS and a reference cohort of persons without DS through the Danish National Hospital Register from January 1, 1977, to May 31, 2008. Poisson regression was used to calculate rate ratios for numbers of overnight hospital admissions and hospital days. During the study period, persons with DS had more than twice the rate of hospital admissions and nearly three times as many bed-days as the population as a whole. Malformations, diseases of the respiratory system, and diseases of the nervous system or sensory organs were the principal indications for hospital admissions. The higher rate ratios for hospital admissions were seen especially among persons less than 20 years of age. Hospitalizations for neoplasms or for diseases of the musculoskeletal system or connective tissue were much less frequent among adults with DS. As survival among persons with DS continues to improve, these findings are likely to be useful for health care planning, although the potential utility may be different for different health care systems.
Related JoVE Video
Risk of cerebral palsy and childhood epilepsy related to infections before or during pregnancy.
PLoS ONE
PUBLISHED: 01-22-2013
Show Abstract
Hide Abstract
Maternal infections during pregnancy have been associated with several neurological disorders in the offspring. However, given the lack of specificity for both the exposures and the outcomes, other factors related to infection such as impaired maternal immune function may be involved in the causal pathway. If impaired maternal immune function plays a role, we would expect infection before pregnancy to be associated with these neurological outcomes.
Related JoVE Video
Childhood epilepsy and maternal antibodies to microbial and tissue antigens during pregnancy.
Epilepsy Res.
PUBLISHED: 01-17-2013
Show Abstract
Hide Abstract
Several epidemiologic studies show associations between mothers infections during pregnancy and an increased risk of mental and neurological disorders in the offspring. Such associations could be due to the direct or indirect effects of infectious agents, including immune responses to infectious agents that display molecular mimicry with host antigens. We measured a range of antigen-specific maternal IgG antibodies to examine if any were associated with risk for childhood epilepsy in offspring.
Related JoVE Video
Cancer risks in parents who had a child with a congenital malformation.
Birth Defects Res. B Dev. Reprod. Toxicol.
PUBLISHED: 01-07-2013
Show Abstract
Hide Abstract
Cancer risk in parents may be related to congenital malformations (CMs) in their children if they share genetic susceptibility or environmental exposure that may be teratogenic and carcinogenic. We conducted a population-based cohort study based on Danish register data. We identified 795,607 mothers and 781,424 fathers who had all their children between 1977 and 2007 in Denmark. Information on CM was obtained from the Danish Hospital Registry and information on cancer was obtained from the Danish Cancer Registry. Parents were followed from the birth of their first child until the diagnosis of cancer, death, emigration, or December 31, 2007. We used Cox regression models to estimate hazard ratios (HRs) for cancer including cancer in specific organs in mothers and fathers. Overall, 75,701 (9.5%) mothers and 72,724 (9.3%) fathers had at least one child diagnosed with CMs within the first year of life. Neither mothers (HR=1.04; 95% CI: 0.99-1.04) nor fathers (HR=1.03; 95% CI: 0.98-1.09) who had a child with a CM had a higher overall risk of cancer. Mothers (HR=0.76, 95% CI: 0.58-1.00) or fathers (HR=0.89, 95% CI: 0.66-1.19) who had a child with a chromosomal malformation had a lower overall cancer risk. The findings also showed a higher risk for some specific types of cancer in parents who had children with a CM in the specific system. Some, or perhaps all, of these findings may be due to chance caused by multiple comparisons. We present all results on paper or online to provide clues for further research and to avoid publication bias.
Related JoVE Video
Maternal bereavement during pregnancy and the risk of stillbirth: a nationwide cohort study in Sweden.
Am. J. Epidemiol.
PUBLISHED: 01-07-2013
Show Abstract
Hide Abstract
Increasing evidence suggests that maternal stress during pregnancy may influence pregnancy outcomes. In a nationwide Swedish study including almost 3 million births taking place during 1973-2006, we investigated whether maternal bereavement during pregnancy is associated with stillbirth risk. Through individual record linkage between several population-based registers, we obtained information on demographic, health-related, and pregnancy-related factors and deaths of mothers first-degree relatives. There were 11,071 stillbirths (3.8 per 1,000 births) in the cohort. After adjustment for potential confounders, infants of mothers who had lost any first-degree relative the year before or during pregnancy had an 18% higher risk of stillbirth than unexposed offspring (95% confidence interval (CI): 1.06, 1.31). Corresponding hazard ratios were 1.67 (95% CI: 1.18, 2.36) for maternal loss of an older child, 2.06 (95% CI: 1.44, 2.94) for loss of a sibling, and 1.07 (95% CI: 0.95, 1.21) for loss of a parent. The relationship between maternal bereavement and stillbirth did not vary by time of death or by whether the relatives death was expected or unexpected. Death of a close relative is one of the most severe sources of stress, and future studies need to investigate whether less severe but more common stressors also increase stillbirth risk.
Related JoVE Video
Congenital cerebral palsy, child sex and parent cardiovascular risk.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Genes associated with cardiovascular disease may also be risk factors for congenital cerebral palsy (CP) and these associations may be modified by sex, since there is an increased risk of CP in male children. We investigated the association between CP of the child with cardiovascular disease in parents, taking sex of the child into consideration.
Related JoVE Video
Psychological Stress and Hospitalization for Childhood Asthma-a Nationwide Cohort Study in Two Nordic Countries.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Exposures to psychological stress in early life may contribute to the development or exacerbation of asthma. We undertook a cohort study based on data from several population-based registers in Denmark and Sweden to examine whether bereavement in childhood led to increased asthma hospitalization.
Related JoVE Video
Related JoVE Video
Early life bereavement and childhood cancer: a nationwide follow-up study in two countries.
BMJ Open
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Childhood cancer is a leading cause of child deaths in affluent countries, but little is known about its aetiology. Psychological stress has been suggested to be associated with cancer in adults; whether this is also seen in childhood cancer is largely unknown. We investigated the association between bereavement as an indicator of severe childhood stress exposure and childhood cancer, using data from Danish and Swedish national registers.
Related JoVE Video
Maternal use of antibiotics and the risk of childhood febrile seizures: a Danish population-based cohort.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
In a large population-based cohort in Denmark to examine if maternal use of antibiotics during pregnancy, as a marker of infection, increases the risk of febrile seizures in childhood in a large population-based cohort in Denmark.
Related JoVE Video
Risk of childhood injuries after prenatal exposure to maternal bereavement: a Danish National Cohort Study.
BMJ Open
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
The aim of this study was to assess the risk of injuries among children exposed to a stressful life exposure (defined as bereavement) before conception or during fetal life.
Related JoVE Video
Thyroglobulin in smoking mothers and their newborns at delivery suggests autoregulation of placental iodide transport overcoming thiocyanate inhibition.
Eur. J. Endocrinol.
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Placental transport of iodide is required for fetal thyroid hormone production. The sodium iodide symporter (NIS) mediates active iodide transport into the thyroid and the lactating mammary gland and is also present in placenta. NIS is competitively inhibited by thiocyanate from maternal smoking, but compensatory autoregulation of iodide transport differs between organs. The extent of autoregulation of placental iodide transport remains to be clarified.
Related JoVE Video
Inhaled glucocorticoids during pregnancy and offspring pediatric diseases: a national cohort study.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 12-28-2011
Show Abstract
Hide Abstract
Glucocorticoid inhalation is the preferred asthma treatment during pregnancy. Previous studies on its safety focused on obstetric outcomes and offspring malformations.
Related JoVE Video
Sex differences in response to anti-tumor necrosis factor therapy in early and established rheumatoid arthritis -- results from the DANBIO registry.
J. Rheumatol.
PUBLISHED: 11-15-2011
Show Abstract
Hide Abstract
To investigate sex differences in response to anti-tumor necrosis factor-? (TNF-?) therapy over time in early versus established rheumatoid arthritis (RA).
Related JoVE Video
Estimating bias from loss to follow-up in the Danish National Birth Cohort.
Epidemiology
PUBLISHED: 09-16-2011
Show Abstract
Hide Abstract
Loss to follow-up in cohort studies may result in biased association estimates. Of 61,895 women entering the Danish National Birth Cohort and completing the first data-collection phase, 37,178 (60%) opted to be in the 7-year follow-up. Using national registry data to obtain end point information on all members of the cohort, we estimated associations in the baseline and the 7-year follow-up participant populations for 5 exposure-outcome associations: (a) size at birth and childhood asthma, (b) assisted reproductive treatment and childhood hospitalizations, (c) prepregnancy body mass index and childhood infections, (d) alcohol drinking in early pregnancy and childhood developmental disorders, and (e) maternal smoking in pregnancy and childhood attention-deficit hyperactivity disorder (ADHD). We estimated follow-up bias in the odds or rate ratios by calculating relative ratios. For all but one of the above analyses, the bias appeared to be small, between -10% and +8%. For maternal smoking in pregnancy and childhood ADHD, we estimated a positive bias of approximately 33% (95% bootstrap limits of -30% and +152%). The presence and magnitude of bias due to loss to follow-up depended on the nature of the factors or outcomes examined, with the most pronounced contribution in this study coming from maternal smoking. Our methods and results may inform bias analyses in future pregnancy cohort studies.
Related JoVE Video
Age at cryptorchidism diagnosis and orchiopexy in Denmark: a population based study of 508,964 boys born from 1995 to 2009.
J. Urol.
PUBLISHED: 08-19-2011
Show Abstract
Hide Abstract
Early treatment for cryptorchidism may be necessary to preserve fertility. International guidelines now recommend that congenital cryptorchidism be treated with orchiopexy before age 1 year. Acquired cryptorchidism should be treated at presentation. To our knowledge the rate of adherence to these guidelines in recent years is unknown. Thus, we present data on age at cryptorchidism diagnosis and orchiopexy in recent Danish birth cohorts.
Related JoVE Video
The Danish National Birth Cohort: selected scientific contributions within perinatal epidemiology and future perspectives.
Scand J Public Health
PUBLISHED: 07-22-2011
Show Abstract
Hide Abstract
In this review a selection of studies published during the period 2002-2010, based on data from the Danish National Birth Cohort linked with other health registers, is described. Illustrative examples of studies addressing perinatal health outcomes (pregnancy complications and fetal and infant health) of a variety of exposures during pregnancy, as well as examples showing different methodological approaches in design and analyses of the studies, are presented.
Related JoVE Video
Infertility, infertility treatment and behavioural problems in the offspring.
Paediatr Perinat Epidemiol
PUBLISHED: 07-19-2011
Show Abstract
Hide Abstract
Behavioural patterns in children of infertile couples may be influenced by both the underlying causes of infertility and stress in the couples. Treatment procedures, such as culture media and manipulation of gametes and embryos, may also result in developmental problems. We examined behavioural problems in children as a function of infertility and infertility treatment, using data from three population-based birth cohorts in Denmark (Aalborg-Odense Birth Cohort, Aarhus Birth Cohort and Danish National Birth Cohort). Information on time to pregnancy and infertility treatment was collected during pregnancy. Children aged between 7 and 21 years were assessed using the Strengths and Difficulties Questionnaire (SDQ). The SDQ was completed by mothers in all cohorts and, in addition, by teachers in the Aarhus cohort and by children themselves in the Aalborg-Odense cohort. Children born after a time to pregnancy of >12 months and no infertility treatment had a behavioural pattern similar to children of fertile parents. Teachers reported a higher total difficulties score for children born after infertility treatment, but no significant differences were seen on any subscales of the teachers report, and neither the mothers nor the children reported any differences on the total difficulties score and the prosocial behaviour score. Our results are thus overall reassuring regarding behavioural problems in children born to infertile couples, regardless of infertility treatment.
Related JoVE Video
Stress during pregnancy and offspring pediatric disease: A National Cohort Study.
Environ. Health Perspect.
PUBLISHED: 07-18-2011
Show Abstract
Hide Abstract
Identifying risk factors for adverse health outcomes in children is important. The intrauterine environment plays a pivotal role for health and disease across life.
Related JoVE Video
Does weight loss improve semen quality and reproductive hormones? Results from a cohort of severely obese men.
Reprod Health
PUBLISHED: 06-21-2011
Show Abstract
Hide Abstract
A high body mass index (BMI) has been associated with reduced semen quality and male subfecundity, but no studies following obese men losing weight have yet been published. We examined semen quality and reproductive hormones among morbidly obese men and studied if weight loss improved the reproductive indicators.
Related JoVE Video
Challenges for epidemiologic research on the verge of a new era.
Eur. J. Epidemiol.
PUBLISHED: 06-08-2011
Show Abstract
Hide Abstract
Although risk factor epidemiology has achieved much, it has its limitations (e.g., a failure to reveal causal mechanisms at multiple levels). To illustrate contemporary challenges for epidemiological research, we present a dialog with examples and argue for incorporating a "systems thinking through a life course" paradigm in epidemiological research. There is an increasing interest in moving part of public health from a discipline concerned primarily with risk factors at the individual level toward one concerned with complex causal patterns which often operate across different levels in time and space (e.g., from the molecular to the population, from the past to the future, and from the distal to the proximal). However, the methodology for discovering these complex and dynamic relationships remains to be improved. We propose strategies for taking up this challenge.
Related JoVE Video
Pregnancy-related pelvic pain is more frequent in women with increased body mass index.
Acta Obstet Gynecol Scand
PUBLISHED: 05-20-2011
Show Abstract
Hide Abstract
To investigate the association between pre-pregnancy overweight/obesity and pregnancy-related pelvic pain.
Related JoVE Video
Unemployment and pregnancy outcomes: a study within the Danish National Birth Cohort.
Scand J Public Health
PUBLISHED: 05-10-2011
Show Abstract
Hide Abstract
To explore the relation between employment status, type of unemployment and pregnancy outcomes.
Related JoVE Video
An investigation of the apparent breast cancer epidemic in France: screening and incidence trends in birth cohorts.
BMC Cancer
PUBLISHED: 05-09-2011
Show Abstract
Hide Abstract
Official descriptive data from France showed a strong increase in breast-cancer incidence between 1980 to 2005 without a corresponding change in breast-cancer mortality. This study quantifies the part of incidence increase due to secular changes in risk factor exposure and in overdiagnosis due to organised or opportunistic screening. Overdiagnosis was defined as non progressive tumours diagnosed as cancer at histology or progressive cancer that would remain asymptomatic until time of death for another cause.
Related JoVE Video
Prenatal exposure to elevated maternal body temperature and risk of epilepsy in childhood: a population-based pregnancy cohort study.
Paediatr Perinat Epidemiol
PUBLISHED: 04-28-2011
Show Abstract
Hide Abstract
Elevated maternal body temperature during pregnancy is of clinical concern as side effects have been reported. We estimated the association between maternal fever and sauna bathing during pregnancy and risk of epilepsy in the offspring. We identified 86,810 liveborn singletons from the Danish National Birth Cohort (DNBC) and followed them for up to 9 years of age. Information on fever including number, timing, level, duration, and symptoms of each fever episodes was collected in two computer-assisted telephone interviews around 17 and 32 gestational weeks; information on maternal use of a sauna was collected in the latter interview, and information on epilepsy was obtained from the Danish National Hospital Register. We applied Cox regression models to estimate the incidence rate ratios (IRR) of epilepsy for children exposed to maternal fever and sauna bathing during pregnancy. Maternal sauna bathing during pregnancy was not associated with an increased risk of epilepsy. Maternal fever during pregnancy in general was not associated with an increased risk of epilepsy in the offspring [IRR = 1.01, 95% confidence interval (CI) 0.85, 1.19], and no dose-response pattern was found according to number, level and duration of fever. However we did find an increased risk of epilepsy among children exposed to at least 3 fever episodes (IRR = 1.88, 95% CI 1.19, 2.98), to maternal fever with symptoms in the urinary system (IRR = 4.86, 95% CI 1.56, 15.17), and to one-day maternal fever of 39.0-39.4°C (IRR = 2.79, 95% CI 1.60, 4.84). Our findings do not support a strong association between hyperthermia and epilepsy but the associations between underlying causes of fever, especially prenatal infections, call for more research.
Related JoVE Video
Maternal shift work during pregnancy and biomarkers of reproductive function among the male offspring--a pilot follow-up study.
Scand J Work Environ Health
PUBLISHED: 04-15-2011
Show Abstract
Hide Abstract
The aim of this study was to examine the associations between maternal shift work during pregnancy and measures of semen quantity and quality and level of reproductive hormones among young, adult men.
Related JoVE Video
Twin study on transplacental-acquired antibodies and attention deficit/hyperactivity disorder--a pilot study.
J. Neuroimmunol.
PUBLISHED: 04-10-2011
Show Abstract
Hide Abstract
We hypothesize that maternal transplacentally acquired antibodies may cause Attention Deficit/Hyperactivity Disorder (ADHD) symptoms years after birth, and tested the hypothesis in twins discordant for ADHD symptoms.
Related JoVE Video
Register-based research: some methodological considerations.
Scand J Public Health
PUBLISHED: 03-22-2011
Show Abstract
Hide Abstract
Collecting new research data is often time consuming and expensive and it may be difficult to recruit volunteers to provide data for research. We should therefore make sure that we do not collect data that already are available and in the Nordic countries we have an opportunity to use national registers for certain types of research. In some situations using these population-based registers is preferable to collecting primary data since selection bias due to nonresponders is not a problem in these registers.
Related JoVE Video
Prenatal cell phone use and developmental milestone delays among infants.
Scand J Work Environ Health
PUBLISHED: 03-14-2011
Show Abstract
Hide Abstract
The aim of this study was to examine if prenatal use of cell phones by pregnant mothers is associated with developmental milestones delays among offspring up to 18 months of age.
Related JoVE Video
Time to pregnancy among women with rheumatoid arthritis.
Arthritis Rheum.
PUBLISHED: 03-08-2011
Show Abstract
Hide Abstract
To assess whether onset of rheumatoid arthritis (RA) prior to conception is associated with a delayed time to pregnancy (TTP).
Related JoVE Video

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.