Mode of birth and long-term maternal mental health: A follow-up study in the Danish National Birth Cohort.

BACKGROUND: Cesarean birth has been associated with increased risks of short-term mental health problems. Little is known about whether these associations persist in the long term. This study aimed to estimate the associations between mode of birth and maternal mental health in midlife while considering mental health before and during pregnancy. METHODS: Cohort study among mothers in the Danish National Birth Cohort. Birth mode for each woman's entire reproductive history was obtained from Danish national registries. Symptoms of depression and stress in midlife were self-reported using validated scales. Log binomial regression was used to calculate risk ratios (RR) with 95% confidence intervals (CI) for the association between birth mode and depressive symptoms. Linear regression was used to calculate mean difference in stress score by birth mode. RESULTS: Among 42,872 women, 15.5% reported depressive symptoms at follow-up, where they were, on average, 43.9 years and 11.2 years after their last birth. Compared with women who only ever had spontaneous vaginal births, women who only had cesarean births, or had both cesarean and vaginal births with the last birth by cesarean, reported slightly more symptoms of depression (RR 1.10, 95% CI 1.01;1.20) and stress (mean difference 0.68 on a 100-point scale, 95% CI 0.10;1.26). CONCLUSION: Whether due to the birth experience or underlying factors, depression and stress in midlife were more frequent in women with only cesarean births or whose last birth was by cesarean compared with women with vaginal births.

Maternal weight change from prepregnancy to 18 months postpartum and subsequent risk of hypertension and cardiovascular disease in Danish women: A cohort study.

BACKGROUND: One-fourth of women experience substantially higher weight years after childbirth. We examined weight change from prepregnancy to 18 months postpartum according to subsequent maternal risk of hypertension and cardiovascular disease (CVD). METHODS AND FINDINGS: We conducted a cohort study of 47,966 women with a live-born singleton within the Danish National Birth Cohort (DNBC; 1997-2002). Interviews during pregnancy and 6 and 18 months postpartum provided information on height, gestational weight gain (GWG), postpartum weights, and maternal characteristics. Information on pregnancy complications, incident hypertension, and CVD was obtained from the National Patient Register. Using Cox regression, we estimated adjusted hazard ratios (HRs; 95% confidence interval [CI]) for hypertension and CVD through 16 years of follow-up. During this period, 2,011 women were diagnosed at the hospital with hypertension and 1,321 with CVD. The women were on average 32.3 years old (range 18.0-49.2) at start of follow-up, 73% had a prepregnancy BMI <25, and 27% a prepregnancy BMI ≥25. Compared with a stable weight (±1 BMI unit), weight gains from prepregnancy to 18 months postpartum of >1-2 and >2 BMI units were associated with 25% (10%-42%), P = 0.001 and 31% (14%-52%), P < 0.001 higher risks of hypertension, respectively. These risks were similar whether weight gain presented postpartum weight retention or a new gain from 6 months to 18 months postpartum and whether GWG was below, within, or above the recommendations. For CVD, findings differed according to prepregnancy BMI. In women with normal-/underweight, weight gain >2 BMI units and weight loss >1 BMI unit were associated with 48% (17%-87%), P = 0.001 and 28% (6%-55%), P = 0.01 higher risks of CVD, respectively. Further, weight loss >1 BMI unit combined with a GWG below recommended was associated with a 70% (24%-135%), P = 0.001 higher risk of CVD. No such increased risks were observed among women with overweight/obesity (interaction by prepregnancy BMI, P = 0.01, 0.03, and 0.03, respectively). The limitations of this observational study include potential confounding by prepregnancy metabolic health and self-reported maternal weights, which may lead to some misclassification. CONCLUSIONS: Postpartum weight retention/new gain in all mothers and postpartum weight loss in mothers with normal-/underweight may be associated with later adverse cardiovascular health.

Menstrual pain and sexual health in mothers-A cross-sectional study in the Danish National Birth Cohort.

INTRODUCTION: Prevalence and consequences of menstrual pain have mainly been studied in younger women. We aimed to describe the prevalence of menstrual pain in mothers and its association with sexual problems. MATERIAL AND METHODS: A cross-sectional study using questionnaire data from the Maternal Follow Up (2013-2014) in the Danish National Birth Cohort (1996-2002). Of 82 569 eligible mothers, 43 639 (53%) completed the follow up. Of these, 24 000 women had a partner, and answered the questions on menstrual pain. Log binomial regression was used to calculate prevalence proportion ratios (PPR) with 95% CI for the association between menstrual pain and specific sexual problems. RESULTS: Menstrual pain was reported by 16 464 women (69%), and severe menstrual pain by 19%. Treatment had previously been requested by 19% of women with menstrual pain. The most common treatment was oral contraceptives, but for 18% of women seeking treatment, no treatment was given. Women with menstrual pain were more likely to report reduced sexual desire (PPR 1.22, 95% CI 1.15-1.29), vaginismus (PPR 1.31, 95% CI 0.96-1.78), and dyspareunia (PPR 1.63, 95% CI 1.47-1.81), in particular deep dyspareunia (PPR 1.92, 95% CI 1.67-2.20). CONCLUSIONS: A majority of Danish mothers in mid-life experienced menstrual pain, and these women more often reported reduced sexual desire, vaginismus, and deep dyspareunia. Few women sought and received treatment for menstrual pain. Healthcare practitioners should be aware that menstrual pain can affect parous women and co-occurs with sexual problems. Future studies should identify barriers to seeking and receiving adequate treatment for menstrual pain.

Examining Nonparticipation in the Maternal Follow-up Within the Danish National Birth Cohort.

A follow-up questionnaire on maternal health was distributed within the Danish National Birth Cohort (established in 1996-2002) 14 years after the index birth. Responses were obtained from 41,466 (53.2%) of 78,010 eligible mothers. To ensure the appropriate use of these data, the possibility of selection bias due to nonparticipation had to be evaluated. We estimated 4 selected exposure-outcome associations (prepregnancy weight-depression; exercise-degenerative musculoskeletal conditions; smoking-heart disease; and alcohol consumption-breast cancer). We adjusted for several factors associated with participation and applied inverse probability weighting. To estimate the degree of selection bias, we calculated relative odds ratios for the relationship between the baseline cohort and the subset participating in the Maternal Follow-up. Participating women were generally healthier, of higher social status, and older than the baseline cohort. However, selection bias in the chosen scenarios was limited; ratios of the odds ratios ranged from -14% to 5% after adjustment for age, parity, social status, and, if the variable was not the exposure variable, prepregnancy body mass index, exercise, smoking, and alcohol consumption. Applying inverse probability weighting did not further reduce bias. In conclusion, while participants differed somewhat from the baseline cohort, selection bias was limited after factors associated with participation status were accounted for.

Participatory System Dynamics Approach Targeting Childhood Health in a Small Danish Community (Children's Cooperation Denmark): Protocol for a Feasibility Study Design.

BACKGROUND: Improving childhood health is complex due to the multifactorial nature and interaction of determinants. Complex problems call for complex intervention thinking, and simple one-size-fits-all solutions do not work to improve childhood health. Early awareness is important, as behavior in childhood often is manifested across adolescence and into adulthood. To facilitate shared understanding of the complex structures and relationships that determine children's health behavior, participatory system approaches in, for example, local communities have shown promising potential. However, such approaches are not used systematically within public health in Denmark, and before being rolled out, they should be tested for their feasibility within this context. OBJECTIVE: This paper describes the study design for Children's Cooperation Denmark (Child-COOP) feasibility study that is aiming to examine the feasibility and acceptability of the participatory system approach and the study procedures for a future scale-up controlled trial. METHODS: The feasibility study is designed as a process evaluation of the intervention with the use of both qualitative and quantitative methods. A local childhood health profile will provide data for childhood health issues, for example, daily physical activity behavior, sleep patterns, anthropometry, mental health, screen use, parental support, and leisure-time activities. Data at system level are collected to assess development in the community, for example, readiness to change, analysis of social networks with stakeholders, rippled effects mapping, and changes in system map. The setting is a small rural town in Denmark, Havndal, with children as the primary target group. Group model building, a participatory system dynamics method, will be used to engage the community, create consensus on the drivers of childhood health, identify local opportunities, and develop context-specific actions. RESULTS: The Child-COOP feasibility study will test the participatory system dynamics approach for intervention and evaluation design and survey objective measures of childhood health behavior and well-being among the ~100 children (6-13 years) attending the local primary school. Community-level data will also be collected. We will assess the contextual factors, implementation of interventions, and mechanisms of impact as part of a process evaluation. Data will be collected at baseline, at 2 years, and 4 years of follow-up. Ethical approval for this study was sought and granted from the Danish Scientific Ethical Committee (1-10-72-283-21). CONCLUSIONS: s: The potential of this participatory system dynamics approach includes opportunities for community engagement and local capacity building to improve children's health and health behavior, and this feasibility study holds the potential to prepare an upscaling of the intervention for effectiveness testing. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/43949.

Mode of delivery and short-term maternal mental health: A follow-up study in the Danish National Birth Cohort.

OBJECTIVE: To estimate associations between mode of delivery and maternal mental health 6 months postpartum. METHODS: Follow-up of mothers in the Danish National Birth Cohort. Symptoms of anxiety, depression or stress were self-reported at gestational week 30 and 6 months postpartum. Mode of delivery was categorized as spontaneous vaginal birth, instrumental vaginal birth, planned cesarean section and emergency cesarean section. Multiple linear and logistic regression models were used to compute differences and odds ratios (ORs) with 95% confidence intervals (CIs) for associations between delivery mode and mental health indicators adjusted for mental health before and during pregnancy. RESULTS: Among 54 474 mothers, mental health indicators improved from pregnancy to 6 months postpartum for all delivery modes. Improvement was smallest in mothers with emergency cesarean section. Thus, compared to women with a spontaneous vaginal birth, women with emergency cesarean section more frequently reported symptoms of anxiety (OR 1.11; 0.98-1.24), depression (OR 1.25; 1.09-1.43) and stress (OR 1.14; 1.01-1.29) 6 months postpartum, and women with planned cesarean section more frequently reported symptoms of anxiety (OR 1.15; 1.01-1.29). CONCLUSION: Mental health improved from pregnancy to 6 months postpartum regardless of delivery mode. Mothers with emergency cesarean section experienced more symptoms of emotional distress 6 months postpartum.

Cause-Specific Stillbirth and Neonatal Death According to Prepregnancy Obesity and Early Gestational Weight Gain: A Study in the Danish National Birth Cohort.

Maternal obesity is associated with impaired fetal and neonatal survival, but underlying mechanisms are poorly understood. We examined how prepregnancy BMI and early gestational weight gain (GWG) were associated with cause-specific stillbirth and neonatal death. In 85,822 pregnancies in the Danish National Birth Cohort (1996-2002), we identified causes of death from medical records for 272 late stillbirths and 228 neonatal deaths. Prepregnancy BMI and early GWG derived from an early pregnancy interview and Cox regression were used to estimate associations with stillbirth or neonatal death as a combined outcome and nine specific cause-of-death categories. Compared to women with normal weight, risk of stillbirth or neonatal death was increased by 66% with overweight and 78% with obesity. Especially deaths due to placental dysfunction, umbilical cord complications, intrapartum events, and infections were increased in women with obesity. More stillbirths and neonatal deaths were observed in women with BMI < 25 and low GWG. Additionally, unexplained intrauterine death was increased with low GWG, while more early stillbirths were seen with both low and high GWG. In conclusion, causes of death that relate to vascular and metabolic disturbances were increased in women with obesity. Low early GWG in women of normal weight deserves more clinical attention.

Associations of birth size, infancy, and childhood growth with intelligence quotient at 5 years of age: a Danish cohort study.

BACKGROUND: The correlates of prenatal and postnatal growth on Intelligence Quotient (IQ) in childhood in term-born children living in high-income countries are not well known. OBJECTIVES: We examined how birth size and growth in infancy and childhood were associated with IQ at age 5 y in term-born children using path analysis. METHODS: The study sample comprised 1719 children from the Danish National Birth Cohort who participated in a substudy in which psychologists assessed IQ using the Wechsler Primary and Preschool Scales of Intelligence-Revised. Measured weight, length/height, and head circumference at birth, 5 mo, 12 mo, and 5 y were included in a path model to estimate their total, indirect, and direct effects on IQ. All growth measures were included in the model as sex- and age-standardized z-scores. RESULTS: After adjusting for potential confounders, a positive association between birth weight and IQ was observed, and 88% of the association was direct. Weight gain in infancy was associated with IQ [per z-score increase from 5 to 12 mo, IQ increased by 1.53 (95% CI: 0.14; 2.92) points] whereas weight gain from 12 mo to 5 y was not associated with IQ. Height and head circumference growth in childhood was associated with IQ [per z-score increase from 12 mo to 5 y, IQ increased by 0.98 (95% CI: 0.17; 1.79) and 2.09 (95% CI: 0.78; 3.41) points, respectively]. CONCLUSIONS: In children born at term in an affluent country with free access to health care, higher IQ was seen with greater size at birth and greater weight gain in infancy. Also, greater growth in height and head circumference throughout the first 5 y of life was associated with higher childhood IQ whereas greater weight gain after the first year of life was not.

Leisure Time Physical Activity, Sedentary Time in Pregnancy, and Infant Weight at Approximately 12 Months.

Background: Maternal leisure time physical activity (LTPA) and sedentary time during pregnancy may influence programming of infant growth in a sex-specific manner. Materials and Methods: Participants (N = 35,212) from the Danish National Birth Cohort reported moderate/vigorous LTPA (hours/week) in early (conception to mean 16 weeks of gestation) and late pregnancy (mean 31 weeks of gestation to delivery) during interviews at 16 weeks of gestation and 6 months postpartum. Participants reported screen time at work and time spent watching television/videos (hours/day) in early pregnancy. Infant weight at 12 months of age was reported by mothers. Weight-for-length was categorized using sex-specific international standards. Results: Participants reported on average 1 hour per week of early pregnancy moderate/vigorous LTPA, 0.5 hour per week of late pregnancy LTPA, and 3 hours per day of early pregnancy sedentary time. Early pregnancy LTPA category was not associated with infant weight (p for trend = 0.62). There were suggested associations of early pregnancy sedentary time above the first quartile with greater odds of infant underweight (odds ratio = 1.15-1.27; p for trend = 0.27). Associations were similar in male and female infants. Conclusions: There is no clear relationship between early or late pregnancy LTPA and infant weight at 12 months in our study. Maternal early pregnancy sedentary time may be associated with infant underweight at 12 months.

Mode of birth and long-term sexual health: a follow-up study of mothers in the Danish National Birth Cohort.

OBJECTIVES: To investigate the relation between mode of birth and women's long-term sexual health. DESIGN: Maternal follow-up of the Danish National Birth Cohort (1996-2002) in 2013-2014 including questions on sexual health. Logistic regression was used to relate registry-based information about mode of birth and perineal tears with data on sexual problems. SETTING: Denmark. PARTICIPANTS: Of 82 569 eligible mothers in the Danish National Birth Cohort, 43 639 (53%) completed the follow-up. Of these, 37 417 women had a partner, and answered at least one question on sexual health. MAIN OUTCOME MEASURES: Self-reported sexual health. RESULTS: Participants were on average 44 years old, and 16 years after their first birth. The frequency of sexual problems among women with only spontaneous vaginal births, the reference group, was 37%. For women who only had caesarean sections, more problems were reported (OR 1.18; 95% CI 1.09 to 1.28). For women who had a spontaneous vaginal birth subsequent to a caesarean, and for women with only vaginal births who had experienced one or more instrumental vaginal births, the odds of sexual problems did not differ from women with only spontaneous vaginal births (OR 1.00; 95% CI 0.91 to 1.11) and (OR 1.01; 95% CI 0.95 to 1.08), respectively. CONCLUSIONS: These findings indicate that caesarean section does not protect against long-term sexual problems. Rather, vaginal birth, even after caesarean section, was associated with fewer long-term sexual problems.

Maternal reproductive history and premenopausal risk of hypertension and cardiovascular disease: a Danish cohort study.

OBJECTIVES: The metabolic changes of pregnancy resemble a cardiovascular risk profile and may persist postpartum, with body mass index (BMI) as a potential modifier. We examined the association between the number of live-birth pregnancies and maternal premenopausal risks of hypertension and cardiovascular disease (CVD), accounting for pre-pregnancy BMI as well as abortions and stillbirths. DESIGN: A prospective cohort study. SETTING: Mothers from the Danish National Birth Cohort (1996 to 2002). For each of these women, registry data on all pregnancies from 1973 to 2011 were obtained, as were self-reported pre-pregnancy weight and height. PARTICIPANTS: A total of 44 552 first-time mothers in the Danish National Birth Cohort. OUTCOME MEASURES: Risks of hypertension and CVD during and between live-birth pregnancies separately and combined as live-birth cycles. RESULTS: After adjustment for abortions, stillbirths, pre-pregnancy BMI and other covariates, a higher risk of hypertension was observed in the first (HR 1.53, 95% CI: 1.37 to 1.72) and fourth and subsequent live-birth cycles (HR 1.72, 95% CI: 1.15 to 2.58), compared with the second. However, as number of live-birth pregnancies increased, risk of hypertension decreased during live-birth pregnancies and increased between live-birth pregnancies (tests for trend, p<0.01). For CVD, we found an overall J-shaped but non-significant association with number of live-birth pregnancies. No interaction with pre-pregnancy BMI (<25 versus ≥25 kg/m2) was observed. CONCLUSIONS: Premenopausal women had the highest risk of hypertension and CVD during their first live-birth pregnancy and after their fourth live-birth pregnancy. All risks were independent of BMI before the first live-birth pregnancy and of number of abortions and stillbirths.

Association of Pre-Pregnancy Body Mass Index, Pregnancy-Related Weight Changes, and Parity With the Risk of Developing Degenerative Musculoskeletal Conditions.

OBJECTIVE: To examine how pre-pregnancy body mass index (BMI), parity, and pregnancy-related weight changes are associated with long-term risk of degenerative musculoskeletal conditions. METHODS: A total of 79,687 mothers with singleton births from the Danish National Birth Cohort were included. Information on height and weight prior to pregnancy and 6 months postpartum as well as gestational weight gain (GWG) was obtained from telephone interviews, while parity was derived from the Danish Medical Birth Registry. Diagnoses of musculoskeletal conditions, including osteoarthritis, disc disorders, low back pain, and soft tissue disorders, were obtained from the Danish National Patient Registry. Hazard ratios (HRs) were estimated using a Cox proportional hazards regression model. RESULTS: The cumulative incidence of musculoskeletal conditions during a median follow-up of 12.4 years was 19.7%. The risk of musculoskeletal conditions increased with both increasing pre-pregnancy BMI and increasing parity. Compared to normal-weight first-time mothers, the highest risk was seen in obese women with >2 births (HR 1.61 [95% confidence interval 1.41-1.83]). GWG of 10-15 kg was associated with the lowest risk of musculoskeletal conditions. Compared to women with no change in weight from preconception to 6 months after childbirth (±1 BMI unit), increasing postpartum weight increased the risk of musculoskeletal conditions in normal-weight and overweight women. CONCLUSION: Our findings indicate that high pre-pregnancy BMI increases the risk of degenerative musculoskeletal conditions. Low and high GWG, higher postpartum weight retention, and especially higher parity are associated with an increased risk. Prevention of being overweight before, during, and after pregnancy may reduce the risk of development of degenerative musculoskeletal conditions among mothers.

Maternal weight change from prepregnancy to 7 years postpartum--the influence of behavioral factors.

OBJECTIVE: We studied the influence of maternal behavior on weight change from prepregnancy to 7 years postpartum. METHODS: We used linear regression to study the independent and combined associations between self-reported behavior in pregnancy (dietary intake, leisure-time exercise, sedentary activity, smoking) and postpartum (breastfeeding duration and smoking) on weights at 6 months, 18 months, and 7 years postpartum. RESULTS: Women's average 7-year weight gain was 2.07 kg, with 23% gaining >5 kg. Multivariable analyses suggested that women with healthier dietary intake, more leisure-time exercise, less sedentary behavior, and longer duration of breastfeeding on average gained 1.66 kg [95% confidence interval (CI): 1.40; 1.91] with a significantly reduced odds [OR 0.56 (95% CI: 0.49; 0.64)] of gaining >5 kg from prepregnancy to 7 years postpartum compared to women with none or one of these behaviors [mean gain 3.03 kg (95% CI: 2.68; 3.39)]. Women who ceased smoking had higher long-term weight gain than nonsmokers, but not smokers. CONCLUSIONS: Adherence to healthy behaviors during pregnancy lowered long-term weight gain considerably by lowering postpartum weight retention and subsequent weight gain. Public health efforts to help mothers achieve healthy behaviors might prevent childbearing-related weight gain.

Maternal prepregnancy waist circumference and BMI in relation to gestational weight gain and breastfeeding behavior: the CARDIA study.

BACKGROUND: Studies suggest that gestational weight gain (GWG) and breastfeeding behavior may influence long-term maternal abdominal fat mass. However, this could be confounded by abdominal fat mass before pregnancy because it is unknown whether abdominal fat mass, independently of body size, affects GWG and breastfeeding behavior. OBJECTIVE: We investigated how maternal prepregnancy fat distribution, described by waist circumference (WC) and body mass index (BMI), is associated with GWG and breastfeeding behavior. DESIGN: We analyzed 1371 live births to 1024 women after enrollment in the Coronary Artery Risk Development in Young Adults study (1985-1996). For each birth, maternal prepregnancy BMI and WC were measured at year 0 (baseline), 2, 5, or 7 examinations. Recalled GWG and breastfeeding behavior were collected at years 7 and 10. GWG was analyzed by using linear regression and breastfeeding behavior by using logistic regression and discrete-time logistic regression. RESULTS: Adjusted for potential confounders, a 1-cm larger WC adjusted for BMI was associated with a 0.19-kg (95% CI: -0.29-, -0.10-kg) lower GWG. In contrast, a 1-unit higher BMI adjusted for WC was associated with a 0.27-kg (95% CI: 0.06-, 0.47-kg) higher GWG. The OR for ever breastfeeding compared with never breastfeeding was 0.93 (95% CI: 0.90, 0.97) per 1-cm larger WC after adjustment for BMI, whereas it was 1.10 (95% CI: 1.02, 1.19) per 1-unit higher BMI adjusted for WC. CONCLUSIONS: Maternal prepregnancy body size was differently associated with GWG and breastfeeding behavior depending on the location of the fat mass. Thus, maternal fat distribution may be a more important determinant of GWG and breastfeeding behavior than BMI alone.

Mental disorders in motherhood according to prepregnancy BMI and pregnancy-related weight changes--A Danish cohort study.

BACKGROUND: Previous studies have shown an association between prepregnancy BMI and postpartum depression, but little is known about this association beyond one year postpartum and the influence of postpartum weight retention (PPWR). METHODS: We used data from 70355 mothers from the Danish National Birth Cohort to estimate the associations between maternal prepregnancy BMI and PPWR, respectively, and incident depression/anxiety disorders until six years postpartum. Outcome was depression or anxiety diagnosed clinically or filling a prescription for an antidepressant. Cox regression was used to estimate hazard ratios (HR) with 95% confidence intervals (CI). Follow-up started at the day of delivery. For the analysis regarding PPWR, follow-up started six months postpartum. RESULTS: Underweight, overweight and obesity were associated with depression and/or anxiety disorders when compared to normal-weight, though the associations were attenuated after adjustments (HR 1.24 [95% CI 1.06-1.45], 1.05 [95% CI 0.96-1.15] and 1.07 [95% CI 0.95-1.21] for underweight, overweight and obese, respectively). Compared to mothers who had returned to their prepregnancy BMI, risk of depression/anxiety disorders was increased for mothers, who from prepregnancy to 6 months postpartum experienced either weight loss >1 BMI unit (HR 1.19 [95% CI 1.06-1.25]), weight gain of 2-3 BMI units (HR 1.23 [95% CI 1.08-1.40]), or weight gain of ≥3 BMI units (HR 1.21 [95% CI 1.05-1.40]). LIMITATION: Causal direction and mechanisms behind the associations are largely unknown. CONCLUSIONS: Low prepregnancy body weight and postpartum weight gain or loss are associated with occurrence of depression and anxiety disorders.

How do pregnancy-related weight changes and breastfeeding relate to maternal weight and BMI-adjusted waist circumference 7 y after delivery? Results from a path analysis.

BACKGROUND: Reproduction has been related to long-term maternal weight gain, and changes in fat mass, with gestational weight gain, have been identified as an important contributor. However, the influence of weight changes during the whole reproductive cycle and the modifying effect of breastfeeding are unknown. OBJECTIVE: The objective was to examine how prepregnancy weight, gestational weight gain, postpartum weight changes, and breastfeeding influence maternal weight and body mass index-adjusted waist circumference (WCBMI) 7 y after delivery. DESIGN: This was a prospective cohort study of 23,701 women participating in the Danish National Birth Cohort with singleton births and no births during follow-up. Path analysis was used to assess the total, direct, and indirect effects; the latter was mediated through weight changes on the pathways. RESULTS: Postpartum weight retention at 6 mo and weight gain from 6 to 18 mo postpartum were highly positively associated with both outcomes. A 1-kg increase in weight retention at 6 mo postpartum corresponded to an average increase of 0.5 kg at 7 y. Gestational weight gain was not associated with WCBMI but was positively associated with weight at 7 y; 87% of this effect was mediated through later weight changes. For both outcomes, a small inverse association was observed for breastfeeding duration. This was strongest for WCBMI, for which 97% of the effect was direct, ie, not mediated through postpartum weight. CONCLUSIONS: These findings show that postpartum weight retention at 6 mo and weight gain from 6 to 18 mo postpartum contribute equally to adverse maternal anthropometric measures 7 y after delivery. Breastfeeding duration may have a beneficial effect.

Association of adherence to lifestyle recommendations and risk of colorectal cancer: a prospective Danish cohort study.

OBJECTIVES: To evaluate the association between a simple lifestyle index based on the recommendations for five lifestyle factors and the incidence of colorectal cancer, and to estimate the proportion of colorectal cancer cases attributable to lack of adherence to the recommendations. DESIGN: Prospective cohort study. SETTING: General population of Copenhagen and Aarhus, Denmark. PARTICIPANTS: 55 487 men and women aged 50-64 years at baseline (1993-7), not previously diagnosed with cancer. MAIN OUTCOME MEASURE: Risk of colorectal cancer in relation to points achieved in the lifestyle index (based on physical activity, waist circumference, smoking, alcohol intake, and diet (dietary fibre, energy percentage from fat, red and processed meat, and fruits and vegetables)) modelled through Cox regression. RESULTS: During a median follow-up of 9.9 years, 678 men and women had colorectal cancer diagnosed. After adjustment for potential confounders, each additional point achieved on the lifestyle index, corresponding to one additional recommendation that was met, was associated with a lower risk of colorectal cancer (incidence rate ratio 0.89 (95% confidence interval 0.82 to 0.96). In this population an estimated total of 13% (95% CI 4% to 22%) of the colorectal cancer cases were attributable to lack of adherence to merely one additional recommendation among all participants except the healthiest. If all participants had followed the five recommendations 23% (9% to 37%) of the colorectal cancer cases might have been prevented. Results were similar for colon and rectal cancer, but only statistically significant for colon cancer. CONCLUSIONS: Adherence to the recommendations for physical activity, waist circumference, smoking, alcohol intake, and diet may reduce colorectal cancer risk considerably, and in this population 23% of the cases might be attributable to lack of adherence to the five lifestyle recommendations. The simple structure of the lifestyle index facilitates its use in public health practice.