Effects of physical activity during pregnancy on preterm delivery and mode of delivery: The Japan Environment and Children's Study, birth cohort study.
ABSTRACT: BACKGROUND:The aim of this study was to examine how physical activity (PA) before and during pregnancy influences pregnancy outcomes, particularly preterm delivery and mode of delivery. METHODS:This study was based on the Japan Environment and Children's Study. A total of 92,796 pregnant women who gave birth to live singleton babies were included. Information on mean PA per week during pregnancy was extracted from the responses to questionnaires completed by women during the second and third trimesters of pregnancy. Information on PA before pregnancy was obtained from questionnaires answered based on recall at participation. The level of PA was stratified into the following quartiles for categorical analysis: Very low, Low, Medium, and High. Pregnancy outcomes, gestational age at delivery (whether preterm delivery or not), and mode of delivery (spontaneous, instrumental, or caesarean delivery) were compared between the different groups adjusted for multiple covariates. RESULTS:With respect to PA during pregnancy, the risk of preterm delivery and instrumental delivery increased significantly in the Very low group compared to that in the Medium group (odds ratios [OR] 1.16, 95% confidence interval [CI], 1.05-1.29; OR 1.12, 95% CI, 1.03-1.22, respectively). Moreover, the risks of caesarean delivery in the Low group and instrumental delivery in the High group were significantly higher than the risks in the Medium group (OR 1.07, 95% CI, 1.00-1.15; OR 1.12, 95% CI, 1.02-1.22, respectively). In contrast, with respect to PA before pregnancy, there were no statistically significant differences when the other groups were compared to the Medium group. CONCLUSIONS:Pre-pregnancy PA has no negative effects on preterm birth and caesarean delivery. In contrast, both may be affected by PA during pregnancy because a low level of PA appears to slightly increase the risk of preterm delivery and operative delivery (caesarean and instrumental).
Project description:<h4>Objectives</h4>To examine pregnancy outcomes among births to women with idiopathic inflammatory myopathy (IIM) in relation to time of IIM diagnosis using population-based data.<h4>Methods</h4>This study used Swedish nationwide registers to identify all singleton births that occurred between 1973 and 2016 among women diagnosed with IIM between 1998 and 2016 and among women unexposed to IIM. We classified births according to the IIM status of the mother at time of delivery: post-IIM (n = 68), 1-3 years pre-IIM (n = 23), >3 years pre-IIM (n = 710) and unexposed to IIM (n = 4101). Multivariate regression models were used to estimate relative risks of adverse pregnancy outcomes in post-IIM births and pre-IIM births separately, in comparison with their non-IIM comparators.<h4>Results</h4>We found that post-IIM births had increased risks of caesarean section [adjusted relative risk (aRR) = 1.98; 95% CI: 1.08, 3.64], preterm birth (aRR = 3.35; 95% CI: 1.28, 8.73) and low birth weight (aRR = 5.69; 95% CI: 1.84, 17.55) compared with non-IIM comparators. We also noticed higher frequencies of caesarean section and instrumental delivery in 1-3 years pre-IIM births than in the non-IIM comparators.<h4>Conclusion</h4>Women who gave birth after IIM diagnosis had higher risks of caesarean section, preterm birth and low birth weight. These results further underline the importance of special care and close monitoring of women with IIM. Higher frequencies of caesarean section and instrumental delivery in pre-IIM births highlight the need for future research on the influence of subclinical features of IIM on pregnancy outcomes.
Project description:<h4>Objective</h4>The objective of this study was to assess the presence of newly acquired preterm birth (PTB) risk factors among primiparous women with no prior history of PTB.<h4>Design</h4>Case-control study.<h4>Setting</h4>Deliveries occurring within a large healthcare system from 2002 to 2012.<h4>Population</h4>Women with their first two consecutive pregnancies carried to ?20(0/7) weeks' gestation.<h4>Methods</h4>Those delivering the first pregnancy at term and the second preterm ?20(0/7) and <37(0/7) weeks (term-preterm cases) were compared with women with a term birth in their first two pregnancies (term-term controls). Social factors with the potential to change between the first and second pregnancies and intrapartum labour characteristics in the first pregnancy were compared between cases and controls.<h4>Main outcome measures</h4>Risk factors for term-preterm sequence.<h4>Results</h4>About 38 215 women met inclusion criteria; 1353 (3.8%) were term-preterm cases. Cases and controls were similar with regard to race/ethnicity and maternal age at the time of the first and second deliveries. Cases delivered their second pregnancy approximately 3 weeks earlier (35.7 versus 39.1, P < 0.001). In multivariable models accounting for known PTB risk factors, women with a caesarean delivery in the first pregnancy [adjusted odds ratio (aOR) = 2.20; 95% confidence interval (CI) 1.57-3.08], new tobacco use (aOR = 2.33; 95% CI 1.61-3.38), and an interpregnancy interval <18 months (aOR = 1.37; 95% CI 1.21-1.55) were at increased risk of term-preterm sequence.<h4>Conclusion</h4>Caesarean delivery in the first pregnancy, new tobacco use, and short interpregnancy interval <18 months are significant risk factors for term-preterm sequence. Women should receive postpartum counselling regarding appropriate interpregnancy interval and cessation of tobacco use.<h4>Tweetable abstract</h4>Caesarean delivery in the 1st pregnancy is a significant risk factor for preterm birth following a term delivery.
Project description:Studies using mothers' self-reported information on birth and pregnancy characteristics are common, but the validity of such data is uncertain. We evaluated questionnaire data from the RHINE III study on reproductive health provided by 715 mothers from Bergen, Norway, about their 1629 births between 1967 and 2010, using the Medical Birth Registry of Norway (MBRN) as gold standard. Validity of dichotomous variables (gender, preterm birth [<37 weeks' gestation], postterm birth [>42 weeks' gestation], induction of labour, forceps delivery, vacuum delivery, caesarean section, were assessed by sensitivity, specificity, positive and negative predictive values (PPV and NPV) and Cohen's kappa. Paired t-test, Pearson's correlation coefficient and Bland-Altman plots were used to validate birthweight, stratified by mother's level of education, parity, birth year and child's asthma status. Child's gender and caesarean section showed high degree of validity (kappa = 0.99, sensitivity and specificity 100%). Instrumental delivery and extremely preterm birth showed good agreement with sensitivity 75-92%. Preterm birth and induction of labour showed moderate agreement. Post-term delivery was poorly reported. The validity appeared to be independent of recall time over 45 years, and of the child's asthma status. Maternally reported birth and pregnancy information is feasible and cheap, showed high validity for important birth and pregnancy parameters, and showed similar risk-associations compared to registry data.
Project description:Preterm delivery is often performed by Caesarean section. We investigated modes of anaesthesia and risk factors for general anaesthesia among women undergoing preterm Caesarean delivery.Women undergoing Caesarean delivery between 24(+0) and 36(+6) weeks' gestation were identified from a multicentre US registry. The mode of anaesthesia was classified as neuraxial anaesthesia (spinal, epidural, or combined spinal and epidural) or general anaesthesia. Logistic regression was used to identify patient characteristic, obstetric, and peripartum risk factors associated with general anaesthesia.Within the study cohort, 11 539 women had preterm Caesarean delivery; 9510 (82.4%) underwent neuraxial anaesthesia and 2029 (17.6%) general anaesthesia. In our multivariate model, African-American race [adjusted odds ratio (aOR)=1.9; 95% confidence interval (CI)=1.7-2.2], Hispanic ethnicity (aOR=1.5; 95% CI=1.2-1.8), other race (aOR=1.4; 95% CI=1.1-1.9), and haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome or eclampsia (aOR=2.8; 95% CI=2.2-3.5) were independently associated with receiving general anaesthesia for preterm Caesarean delivery. Women with an emergency Caesarean delivery indication had the highest odds for general anaesthesia (aOR=3.5; 95% CI=3.1-3.9). For every 1 week decrease in gestational age at delivery, the adjusted odds of general anaesthesia increased by 13%.In our study cohort, nearly one in five women received general anaesthesia for preterm Caesarean delivery. Although potential confounding by unmeasured factors cannot be excluded, our findings suggest that early gestational age at delivery, emergent Caesarean delivery indications, hypertensive disease, and non-Caucasian race or ethnicity are associated with general anaesthesia for preterm Caesarean delivery.
Project description:<h4>Objective</h4>The aim of the present study was to evaluate the single and joint associations of maternal prepregnancy body mass index (BMI) and gestational weight gain (GWG) with pregnancy outcomes in Tianjin, China.<h4>Methods</h4>Between June 2009 and May 2011, health care records of 33,973 pregnant women were collected and their children were measured for birth weight and birth length. The independent and joint associations of prepregnancy BMI and GWG based on the Institute of Medicine (IOM) guidelines with the risks of pregnancy and neonatal outcomes were examined by using Logistic Regression.<h4>Results</h4>After adjustment for all confounding factors, maternal prepregnancy BMI was positively associated with risks of gestational diabetes mellitus (GDM), pregnancy-induced hypertension, caesarean delivery, preterm delivery, large-for-gestational age infant (LGA), and macrosomia, and inversely associated with risks of small-for-gestational age infant (SGA) and low birth weight. Maternal excessive GWG was associated with increased risks of pregnancy-induced hypertension, caesarean delivery, LGA, and macrosomia, and decreased risks of preterm delivery, SGA, and low birth weight. Maternal inadequate GWG was associated with increased risks of preterm delivery and SGA, and decreased risks of LGA and macrosomia, compared with maternal adequate GWG. Women with both prepregnancy obesity and excessive GWG had 2.2-5.9 folds higher risks of GDM, pregnancy-induced hypertension, caesarean delivery, LGA, and macrosomia compared with women with normal prepregnancy BMI and adequate GWG.<h4>Conclusions</h4>Maternal prepregnancy obesity and excessive GWG were associated with greater risks of pregnancy-induced hypertension, caesarean delivery, and greater infant size at birth. Health care providers should inform women to start the pregnancy with a BMI in the normal weight category and limit their GWG to the range specified for their prepregnancy BMI.
Project description:<h4>Objective</h4>Mitochondrial disease is a disorder of energy metabolism that affects 1 in 4300 adults in the UK. Pregnancy is associated with physiological demands that have implications for energy metabolism. We were interested to know how pregnancy was affected in women with mitochondrial disease, particularly those with the most common pathogenic mutation m.3243A>G.<h4>Design</h4>Retrospective case-comparison study.<h4>Population/setting</h4>Sixty-seven women with genetically confirmed mitochondrial disease from the UK Mitochondrial Diseases Cohort and 69 unaffected women participated.<h4>Methods</h4>Participants answered questionnaires regarding each of their pregnancies. Patients were divided into two groups according to genetic mutation, with those harbouring m.3243A>G comprising a single group.<h4>Main outcome measures</h4>Pregnancy-related complications, mode of delivery, gestational age and birthweight of newborns.<h4>Results</h4>Of 139 live births in the comparison group, 62 were in the m.3243A>G group and 87 were in the 'all other mutations' group. Pregnancies of women with the m.3243A>G mutation had significantly more gestational diabetes (odds ratio [OR] = 8.2, 95% CI 1.3-50.1), breathing difficulties (OR = 7.8, 95% CI 1.0-59.1) and hypertension (OR = 8.2, 95% CI 3.1-21.5) than the comparison group. Only half of the pregnancies in the m.3243A>G group had normal vaginal delivery, with emergency caesarean section accounting for 24.2% of deliveries. Babies were born significantly earlier to mothers harbouring m.3243A>G with 53.3% of them preterm (<37 weeks). These babies were also more likely to require resuscitation and admission.<h4>Conclusion</h4>Women who carried the m.3243A>G mutation appeared to be at higher risk of complications during pregnancies, caesarean section and preterm delivery than the unaffected women or those with other forms of mitochondrial disease.<h4>Tweetable abstract</h4>Pregnant women with mitochondrial disease - m.3243A>G mutation - are at greatly increased risk of complications and preterm delivery.
Project description:<h4>Background</h4>Preterm labour, between 24 to 28 weeks of gestation, remains prevalent in low resource settings. There is evidence of improved survival after 24 weeks though the ideal mode of delivery remains unclear. There are no clear management protocols to guide patient management. We sought to determine the incidence of preterm labour occurring between 24 to 28 weeks, its associated risk factors and the preferred mode of delivery in a low resource setting with the aim of streamlining patient care.<h4>Methods</h4>Between February 2020 and September 2020, we prospectively followed 392 women with preterm labour between 24 to 28 weeks of gestation and their newborns from admission to discharge at Kawempe National Referral hospital in Kampala, Uganda. The primary outcome was perinatal mortality associated with the different modes of delivery. Secondary outcomes included neonatal and maternal infections, admission to the Neonatal Special Care Unit (SCU), need for neonatal resuscitation, preterm birth and maternal death. Chi-square test was used to assess the association between perinatal mortality and categorical variables such as parity, mode of delivery, employment status, age, antepartum hemorrhage, digital vaginal examination, and admission to Special Care unit. Multivariate logistic regression was used to assess the association between comparative outcomes of the different modes of delivery and maternal and neonatal risk factors.<h4>Results</h4>The incidence of preterm labour among women who delivered preterm babies between 24 to 28 weeks was 68.9% 95% CI 64.2-73.4). Preterm deliveries between 24 to 28 weeks contributed 20% of the all preterm deliveries and 2.5% of the total hospital deliveries. Preterm labour was independently associated with gravidity (p-value = 0.038), whether labour was medically induced (p-value <0.001), number of digital examinations (p-value <0.001), history of vaginal bleeding prior to onset of labour (p-value < 0.001), whether tocolytics were given (p-value < 0.001), whether an obstetric ultrasound scan was done (p-value <0.001 and number of babies carried (p-value < 0.001). At multivariate analysis; multiple pregnancy OR 15.45 (2.00-119.53), p-value < 0.001, presence of fever prior to admission OR 4.03 (95% CI .23-13.23), p-value = 0.002 and duration of drainage of liquor OR 0.16 (0.03-0.87), p-value = 0.034 were independently associated with preterm labour. The perinatal mortality rate in our study was 778 per 1000 live births. Of the 392 participants, 359 (91.5%), had vaginal delivery, 29 (7.3%) underwent Caesarean delivery and 4 (1%) had assisted vaginal delivery. Caesarean delivery was protective against perinatal mortality compared to vaginal delivery OR = 0.36, 95% CI 0.14-0.82, p-value = 0.017). The other protective factors included receiving antenatal corticosteroids OR = 0.57, 95% CI 0.33-0.98, p-value = 0.040, Doing 3-4 digital exams per day, OR = 0.41, 95% 0.18-0.91, p-value = 0.028) and hospital stay of > 7 days, p value = 0.001. Vaginal delivery was associated with maternal infections, postpartum hemorrhage, and admission to the Special Care Unit.<h4>Conclusion</h4>Caesarean delivery is the preferred mode of delivery for preterm deliveries between 24 to 28 weeks of gestation especially when labour is not established in low resource settings. It is associated with lesser adverse pregnancy outcomes when compared to vaginal delivery for remote gestation ages.
Project description:<h4>Objectives</h4>To investigate the impact of maternal age on pregnancy outcomes with special emphasis on adolescents and older mothers and to investigate the differences in demographic profile between adolescents and older mothers.<h4>Methods</h4>This study is a secondary analysis of pregnancy outcomes of women in Riyadh Mother and Baby cohort study according to maternal age. The study population was grouped according to maternal age into five subgroups; <20, 20-29, 30-34, 35-39 and 40+years. The age group 20-29 years was considered as a reference group. Investigation of maternal age impact on maternal and neonatal outcomes was conducted with adjustment of confounders using regression models.<h4>Results</h4>All mothers were married when conceived with the index pregnancy. Young mothers were less likely to be illiterate, more likely to achieve higher education and be employed compared with mothers ? 40 years. Compared with the reference group, adolescents were more likely to have vaginal delivery (and least likely to deliver by caesarean section (CS); OR=0.6, 95%?CI 0.4 to 0.9, while women ?40 years, were more likely to deliver by CS; OR 2.9, 95%?CI 2.3 to 3.7. Maternal age was a risk factor for gestational diabetes in women ?40 years; OR 1.7, 95%?CI 1.3 to 2.1. Adolescents had increased risk of preterm delivery; OR 1.5, 95%?CI 1.1 to 2.1 and women ?40 years had similar risk; OR, 1.3, 95%?CI 1.1 to 1.6.<h4>Conclusion</h4>Adverse pregnancy outcomes show a continuum with the advancement of maternal age. Adolescents mother are more likely to have vaginal delivery; however, they are at increased risk of preterm delivery. Advanced maternal age is associated with increased risk of preterm delivery, gestational diabetes and CS.
Project description:BACKGROUND:Reliable, population-based data on pregnancy-related morbidity and mortality, and risk factors for fatal foetal outcomes are scarce for low- and middle-income countries. Yet, such data are essential for understanding and improving maternal and neonatal health and wellbeing. METHODS:Within the 4-monthly surveillance rounds of the Taabo health and demographic surveillance system (HDSS) in south-central Côte d'Ivoire, all women of reproductive age identified to be pregnant between 2011 and 2014 were followed-up. A questionnaire pertaining to antenatal care, pregnancy-related morbidities, delivery circumstances, and birth outcome was administered to eligible women. Along with sociodemographic information retrieved from the Taabo HDSS repository, these data were subjected to penalized maximum likelihood logistic regression analysis, to determine risk factors for fatal foetal outcomes. RESULTS:A total of 2976 pregnancies were monitored of which 118 (4.0%) resulted in a fatal outcome. Risk factors identified by multivariable logistic regression analysis included sociodemographic factors of the expectant mother, such as residency in a rural area (adjusted odds ratio (aOR)?=?2.87; 95% confidence interval (CI) 1.31-6.29) and poorest wealth tertile (aOR?=?1.79; 95% CI 1.02-3.14), a history of miscarriage (aOR?=?23.19; 95% CI 14.71-36.55), non-receipt of preventive treatment such as iron/folic acid supplementation (aOR?=?3.15; 95% CI 1.71-5.80), only two doses of tetanus vaccination (aOR?=?2.59; 95% CI 1.56-4.30), malaria during pregnancy (aOR?=?1.94; 95% CI 1.21-3.11), preterm birth (aOR?=?4.45; 95% CI 2.82-7.01), and delivery by caesarean section (aOR?=?13.03; 95% CI 4.24-40.08) or by instrumental delivery (aOR?=?5.05; 95% CI 1.50-16.96). Women who paid for delivery were at a significantly lower odds of a fatal foetal outcome (aOR?=?0.39; 95% CI 0.25-0.74). CONCLUSIONS:We identified risk factors for fatal foetal outcomes in a mainly rural HDSS site of Côte d'Ivoire. Our findings call for public health action to improve access to, and use of, quality services of ante- and perinatal care.
Project description:OBJECTIVES:To examine the association between postpartum urinary tract infection and intended mode of delivery as well as actual mode of delivery. DESIGN:Retrospective cohort study. SETTING AND PARTICIPANTS:All live births in Denmark between 2004 and 2010 (n=450?856). Births were classified by intended caesarean delivery (n=45?053) or intended vaginal delivery (n=405?803), and by actual mode of delivery: spontaneous vaginal delivery, operative vaginal delivery, emergency or planned caesarean delivery in labour or prelabour. PRIMARY AND SECONDARY OUTCOME MEASURES:The primary outcome measure was postpartum urinary tract infection (n=16?295) within 30 days post partum, defined as either a diagnosis of urinary tract infection in the National Patient Registry or redemption of urinary tract infection-specific antibiotics recorded in the Register of Medicinal Product Statistics. RESULTS:We found that 4.6% of women with intended caesarean delivery and 3.5% of women with intended vaginal delivery were treated for postpartum urinary tract infection.Women with intended caesarean delivery had a significantly increased risk of postpartum urinary tract infection compared with women with intended vaginal delivery (OR 1.33, 95% CI 1.27 to 1.40), after adjustment for age at delivery, smoking, body mass index, educational level, gestational diabetes mellitus, infection during pregnancy, birth weight, preterm delivery, preterm prelabour rupture of membranes, pre-eclampsia, parity and previous caesarean delivery (adjusted OR 1.24, 95% CI 1.17 to 1.46).Using actual mode of delivery as exposure, all types of operative delivery had an equally increased risk of postpartum urinary tract infection compared with spontaneous vaginal delivery. CONCLUSIONS:Compared with intended vaginal delivery, intended caesarean delivery was significantly associated with a higher risk of postpartum urinary tract infection. Future studies should focus on reducing routine catheterisation prior to operative vaginal delivery as well as improving procedures related to catheterisation.