Katrine Mari Owe

Correlates of regular exercise during pregnancy: the Norwegian Mother and Child Cohort Study

The aims of this study were to describe the level of exercise during pregnancy and to assess factors associated with regular exercise. Using data from the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health, 34 508 pregnancies were included in the present study. Data were collected by self‐completed questionnaires in gestational weeks 17 and 30, and analyzed by logistic regression analysis. The results are presented as adjusted odds ratios (aOR) with a 95% confidence interval. The proportion of women exercising regularly was 46.4% before pregnancy and decreased to 28.0 and 20.4% in weeks 17 and 30, respectively. Walking and bicycling were the most frequently reported activities before and during pregnancy. The prevalence of swimming tended to increase from prepregnancy to week 30. Exercising regularly prepregnancy was highly related to regular exercise in week 17, aOR=18.4 (17.1–19.7) and 30, aOR 4.3 (4.1–4.6). Low gestational weight gain was positively associated with regular exercise in week 30, aOR=1.2 (1.1–1.4), whereas being overweight before pregnancy was inversely associated with regular exercise in week 17, aOR=0.8 (0.7–0.8) and 30, aOR=0.7 (0.6–0.7). Also, women experiencing a multiple pregnancy, pelvic girdle pain, or nausea were less likely to exercise regularly.

Recreational Physical Activity and the Risk of Preeclampsia: A Prospective Cohort of Norwegian Women

Previous case-control studies suggest that recreational physical activity protects against preeclampsia. Using a prospective design, the authors estimated the risk of preeclampsia for pregnant women according to level of physical activity, taking other variables that influence risk into consideration. The data set comprised 59,573 pregnancies from the Norwegian Mother and Child Cohort Study (1999-2006). Information on physical activity and other exposures was extracted from questionnaire responses given in pregnancy weeks 14-22, whereas diagnosis of preeclampsia was retrieved from the Medical Birth Registry of Norway. Estimation and confounder control was performed with multiple logistic regression. About 24% of pregnant women reported no physical activity, and 7% reported more than 25 such activities per month. The adjusted odds ratio was 0.79 (95% confidence interval: 0.65, 0.96) for preeclampsia when comparing women who exercised 25 times or more per month with inactive women. The association appeared strongest among women whose body mass index was less than 25 kg/m(2) and was absent among women whose body mass index was higher than 30 kg/m(2). These results suggest that the preventive effect of recreational physical activity during pregnancy may be more limited than has been shown in case-control studies and may apply to nonobese women only.

Association between regular exercise and excessive newborn birth weight

OBJECTIVE: To estimate the association between regular exercise before and during pregnancy and excessive newborn birth weight. METHODS: Using data from the Norwegian Mother and Child Cohort Study, 36,869 singleton pregnancies lasting at least 37 weeks were included. Information on regular exercise was based on answers from two questionnaires distributed in pregnancy weeks 17 and 30. Linkage to the Medical Birth Registry of Norway provided data on newborn birth weight. The main outcome measure was excessive newborn birth weight, defined as birth weight at or above the 90th percentile. Logistic regression analyses were used to estimate the associations separately for nulliparous (n=16,064) and multiparous (n=20,805) women, and the results are presented as adjusted odds ratios (aORs) with 95% confidence intervals (95% CIs). RESULTS: Excessive newborn birth weight was observed in 4,033 (10.9%) newborns, 56.1% (n=2,263) of whom were born to multiparous women. An inverse association between regular exercise (at least three times per week) and excessive newborn birth weight in pregnancy weeks 17 and 30 was observed in nulliparous women, aOR 0.72 (95% CI 0.56–0.93) and aOR 0.77 (95% CI 0.61–0.96), respectively. Regular exercise performed before pregnancy did not affect the probability of delivering newborns with an excessive birth weight in nulliparous or multiparous women. CONCLUSION: Regular exercise during pregnancy reduces the odds of giving birth to newborns with excessive birth weight by 23–28%.

Guidelines for Physical Activity During Pregnancy Comparisons From Around the World

Introduction. Women attain numerous benefits from physical activity during pregnancy. However, because of physical changes that occur during pregnancy, special precautions are also needed. This review summarizes current guidelines for physical activity among pregnant women worldwide. Methods. We searched PubMed (MedLINE) for country-specific governmental and clinical guidelines on physical activity during pregnancy through the year 2012. We cross-referenced with articles referring to guidelines, with only the most recent included. An abstraction form was used to extract key details and summarize. Results. In total, 11 guidelines were identified from 9 countries (Australia, Canada, Denmark, France, Japan, Norway, Spain, United Kingdom, United States). Most guidelines supported moderate-intensity physical activity during pregnancy (10/11) and indicated specific frequency (9/11) and duration/time (9/11) recommendations. Most guidelines provided advice on initiating an exercise program during pregnancy (10/11). Six guidelines included absolute and relative contraindications to exercise. All guidelines generally ruled-out sports with risks of falls, trauma, or collisions. Six guidelines included indications for stopping exercise during pregnancy. Conclusion. This review contrasted pregnancy-related physical activity guidelines from around the world, and can help inform new guidelines as they are created or updated and facilitate the development of a worldwide guideline.

Do pregnant women follow exercise guidelines? Prevalence data among 3482 women, and prediction of low-back pain, pelvic girdle pain and depression

Purpose We describe exercise level in mid-pregnancy, associated sociodemographic variables, and investigate the association between exercise in mid-pregnancy and subsequent low-back pain, pelvic girdle pain and depression at 32 weeks of pregnancy. Material and methods The study included 3482 pregnant women participating in the Akershus Birth Cohort study (response rate 80.5%). Data were collected by a questionnaire in pregnancy weeks 17–21, pregnancy week 32 and electronic birth journal. The results were analysed by logistic regression and are presented as crude (cOR) and adjusted OR (aOR) with 95% CI. Results Only 14.6% of the respondents followed the current exercise prescription for exercise during pregnancy (≥3 times a week, >20 min at moderate intensity). One-third of the study sample exercised less than once a week at pregnancy weeks 17–21. Women exercising either 1–2 times or ≥3 times a week at mid-pregnancy were more often primiparous, higher-educated and had less often prepregnacy body mass index >30 kg/m2 compared with women exercising less than once a week. Women who exercised ≥3 times a week were less likely to report pelvic girdle pain (aOR: 0.76, 95% CI 0.61 to 0.96), while women exercising 1–2 times a week were less likely to report low-back pain (aOR: 0.80, 95% CI 0.66 to 0.97) and depression (aOR: 0.66, 95% CI 0.48 to 0.91). Conclusions Few Norwegian women follow current exercise prescriptions for exercise in mid-pregnancy. The results may indicate an association between exercising mid-pregnancy and lower prevalence of low-back pain, pelvic girdle pain and depression in late pregnancy.

Exercise during Pregnancy and the Gestational Age Distribution: A Cohort Study

PURPOSE The studys purpose was to examine the associations between exercise performed at different time points during pregnancy and gestational age (GA) in a population-based cohort study. METHODS Data included 61,098 singleton pregnancies enrolled between 2000 and 2006 in the Norwegian Mother and Child Cohort Study, conducted by the Norwegian Institute of Public Health. Self-reported exercise was collected from two questionnaires in pregnancy weeks 17 and 30. GA was determined on the basis of the expected date of delivery according to ultrasound, as registered in the Medical Birth Registry of Norway. We used logistic regression to analyze preterm (<37 completed weeks) and postterm births (≥ 42 wk). Comparison of mean GA by exercise levels was estimated by a general linear model. RESULTS Mean GA for women exercising three to five times a week in week 17 was 39.51 (95% confidence interval [CI] = 39.48-39.54) compared with 39.34 (95% CI = 39.30-39.37) completed weeks for nonexercisers (P < 0.001). Mean differences remained for all categories of exercise after adjusting for confounding with the greatest mean difference between exercising three to five times per week in week 17 and nonexercisers (equals 1 d). Similar mean differences in GA were observed by exercise levels in week 30. The greatest protective effect on risk of preterm birth was observed for women exercising three to five times a week in week 17 or 30 (adjusted odds ratio (aOR) = 0.82, 95% CI = 0.73-0.91 and aOR = 0.74, 95% CI = 0.65-0.83, respectively) compared with nonexercisers. On the other hand, women exercising one to two or three to five times per week in week 17 were slightly more likely to have a postterm birth (aOR = 1.14, 95% CI = 1.04-1.24 and aOR = 1.15, 95% CI = 1.04-1.26, respectively). Mean GA did not differ by type of exercise performed during pregnancy. CONCLUSIONS Exercise performed during pregnancy shifted the GA distribution slightly upward resulting in reduced preterm births and slightly increased postterm births.

Summary of international guidelines for physical activity after pregnancy.

Postpartum physical activity can improve mood, maintain cardiorespiratory fitness, improve weight control, promote weight loss, and reduce depression and anxiety. This review summarizes current guidelines for postpartum physical activity worldwide. PubMed (MEDLINE) was searched for country-specific government and clinical guidelines on physical activity after pregnancy through the year 2013. Only the most recent guideline was included in the review. An abstraction form facilitated extraction of key details and helped to summarize results. Six guidelines were identified from 5 countries (Australia, Canada, Norway, United Kingdom, and United States). All guidelines were embedded within pregnancy-related physical activity recommendations. All provided physical activity advice related to breastfeeding and 3 remarked about physical activity after cesarean delivery. Recommended physical activities mentioned in the guidelines included aerobic (3/6), pelvic floor exercise (3/6), strengthening (2/6), stretching (2/6), and walking (2/6). None of the guidelines discussed sedentary behavior. The guidelines that were identified lacked specificity for physical activity. Greater clarity in guidelines would be more useful to both practitioners and the women they serve. Postpartum physical activity guidelines have the potential to assist women to initiate or resume physical activity after childbirth so that they can transition to meeting recommended levels of physical activity. Health care providers have a critical role in encouraging women to be active at this time, and the availability of more explicit guidelines may assist them to routinely include physical activity advice in their postpartum care. Target Audience Obstetricians and gynecologists, family physicians Learning Objectives After completing this CME activity, physicians should be better able to describe the benefits of physical activity identified in postpartum physical activity guidelines, discuss the impacts of physical activity on breastfeeding as described in postpartum physical activity guidelines, and assess the limitations of the current postpartum physical activity guidelines.

Physical activity during pregnancy and language development in the offspring

BACKGROUND In rodents, physical activity during pregnancy has been associated with improved learning and memory in the offspring. We used data from the Avon Longitudinal Study of Parents and Children (born in 1991-92) to investigate maternal physical activity during pregnancy and offspring language development. METHODS At 18 weeks of gestation, women reported the hours per week they participated in 11 leisure-time physical activities and the hours per week spent in general physical activity (leisure, household and occupational). Caregivers completed a modified MacArthur Infant Communication scale at 15 months. Verbal intelligence quotient (IQ) was measured at age 8 years. Regression analysis was used to examine the associations of physical activity with MacArthur score (more than 75th percentile) and verbal IQ. The number of participants available for analyses ranged from 4529 to 7162. RESULTS Children of women in the two highest quintiles of leisure activity (compared with no leisure activity) were more likely to have high 15-month MacArthur scores (adjusted odds ratio 1.2 [95% confidence interval 0.9, 1.4] and adjusted odds ratio 1.4 [95% CI 1.1, 1.7], respectively). Leisure activity was not associated with IQ, while general physical activity was linked with lower verbal IQ (1 and 3 points lower for the two highest quintiles). CONCLUSIONS The most robust finding was a transient increase in offspring vocabulary score at young ages with maternal leisure activity. Differences in the associations with leisure-time physical activity compared with general physical activity need further exploration.

Pelvic pain after childbirth: a longitudinal population study.

Abstract In this longitudinal population study, the aims were to study associations of mode of delivery with new onset of pelvic pain and changes in pelvic pain scores up to 7 to 18 months after childbirth. We included 20,248 participants enrolled in the Norwegian Mother and Child Cohort Study (1999-2008) without preexisting pelvic pain in pregnancy. Data were obtained by 4 self-administered questionnaires and linked to the Medical Birth Registry of Norway. A total of 4.5% of the women reported new onset of pelvic pain 0 to 3 months postpartum. Compared to unassisted vaginal delivery, operative vaginal delivery was associated with increased odds of pelvic pain (adjusted odds ratio [OR]: 1.30; 95% confidence interval [CI]: 1.06-1.59). Planned and emergency cesarean deliveries were associated with reduced odds of pelvic pain (adjusted OR: 0.48; 95% CI: 0.31-0.74 and adjusted OR: 0.65; 95% CI: 0.49-0.87, respectively). Planned cesarean delivery, young maternal age, and low Symptom Checklist-8 scores were associated with low pelvic pain scores after childbirth. A history of pain was the only factor associated with increased pelvic pain scores over time (P = 0.047). We conclude that new onset of pelvic pain after childbirth was not commonly reported, particularly following cesarean delivery. Overall, pelvic pain scores were rather low at all time points and women with a history of pain reported increased pelvic pain scores over time. Hence, clinicians should follow up women with pelvic pain after a difficult childbirth experience, particularly if they have a history of pain.

Exercise during pregnancy and risk of cesarean delivery in nulliparous women: a large population-based cohort study

BACKGROUND Vaginal delivery for the first birth is of great importance for further obstetric performance for the individual woman. Given the rising cesarean delivery rates worldwide over the past decades, a search for modifiable factors that are associated with cesarean delivery is needed. Exercise may be a modifiable factor that is associated with type of delivery, but the results of previous studies are not conclusive. OBJECTIVE The purpose of this study was to investigate the association between exercise during pregnancy and cesarean delivery, both acute and elective, in nulliparous women. STUDY DESIGN We conducted a population-based cohort study that involved 39,187 nulliparous women with a singleton pregnancy who were enrolled in the Norwegian Mother and Child Cohort Study between 2000 and 2009. All women answered 2 questionnaires in pregnancy weeks 17 and 30. Acute and elective cesarean delivery data were obtained from the Medical Birth Registry of Norway. Information on exercise frequency and type was assessed prospectively by questionnaires in pregnancy weeks 17 and 30. Generalized linear models estimated risk differences of acute and elective cesarean delivery for different frequencies and types of exercise during pregnancy weeks 17 and 30. We used restricted cubic splines to examine dose-response associations of exercise frequency and acute cesarean delivery. A test for nonlinearity was also conducted. RESULTS The total cesarean delivery rate was 15.4% (n=6030), of which 77.8% (n=4689) was acute cesarean delivery. Exercise during pregnancy was associated with a reduced risk of cesarean delivery, particularly for acute cesarean delivery. A nonlinear association was observed for exercise frequency in weeks 17 and 30 and risk of acute cesarean delivery (test for nonlinearity, P=.003 and P=.027, respectively). The largest risk reduction was observed for acute cesarean delivery among women who exercised >5 times weekly during weeks 17 (-2.2%) and 30 (-3.6%) compared with nonexercisers (test for trend, P<.001). Reporting high impact exercises in weeks 17 and 30 was associated with the greatest reduction in risk of acute cesarean delivery (-3.0% and -3.4%, respectively). CONCLUSION Compared with nonexercisers, regular exercise and high-impact exercises during pregnancy are associated with reduced risk of having an acute cesarean delivery in first-time mothers.