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Background

Unintended pregnancy, a pregnancy that have been either unwanted or mistimed, is a serious public health issue in Brazil. It is reported for more than half of women who gave birth in the country, but the characteristics of women who conceive unintentionally are rarely documented. The aim of this study is to analyse the prevalence and the association between unintended pregnancy and a set of sociodemographic characteristics, individual-level variables and history of obstetric outcomes.

Methods

Birth in Brazil is a cross-sectional study with countrywide representation that interviewed 23,894 women after birth. The information about intendedness of pregnancy was obtained after birth at the hospital and classified into three categories: intended, mistimed or unwanted. Multinomial regression analysis was used to estimate the associations between intendedness of a pregnancy, and sociodemographic and obstetric variables, calculating odds ratios and 95 % confidence intervals. All significant variables in the bivariate analysis were included in the multinomial multivariate model and the final model retaining variables that remained significant at the 5 % level.

Results

Unintended pregnancy was reported by 55.4 % of postpartum women. The following variables maintained positive and significant statistical associations with mistimed pregnancy: maternal age?<?20 years (OR?=?1.89, 95 % CI: 1.68–2.14); brown (OR?=?1.15, 95 % CI: 1.04–1.27) or yellow skin color (OR?=?1.56, 95 % CI: 1.05–2.32); having no partner (OR?=?2.32, 95 % CI: 1.99–2.71); having no paid job (OR?=?1.15, 95 % CI: 1.04–1.27); alcohol abuse with risk of alcoholism (OR?=?1.25, 95 % CI: 1.04–1.50) and having had three or more births (OR?=?2.01, 95 % CI: 1.63–2.47). The same factors were associated with unwanted pregnancy, though the strength of the associations was generally stronger. Women with three or more births were 14 times more likely to have an unwanted pregnancy, and complication in the previous pregnancies and preterm birth were 40 % and 19 % higher, respectively. Previous neonatal death was a protective factor for both mistimed (OR?=?0.61, 95 % CI: 0.44–0.85) and unwanted pregnancy (OR?=?0.44, 95 % CI: 0.34–0.57).

Conclusions

This study confirms findings from previous research about the influence of socioeconomic and individual risk factors on unintended pregnancy. It takes a new approach to the problem by showing the importance of previous neonatal death, preterm birth and complication during pregnancy as risk factors for unintended pregnancy.
  相似文献   
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Background

The participation of nurses and midwives in vaginal birth care is limited in Brazil, and there are no national data regarding their involvement. The goal was to describe the participation of nurses and nurse-midwives in childbirth care in Brazil in the years 2011 and 2012, and to analyze the association between hospitals with nurses and nurse-midwives in labor and birth care and the use of good practices, and their influence in the reduction of unnecessary interventions, including cesarean sections.

Methods

Birth in Brazil is a national, population-based study consisting of 23,894 postpartum women, carried out in the period between February 2011 and October 2012, in 266 healthcare settings. The study included all vaginal births involving physicians or nurses/nurse-midwives. A logistic regression model was used to examine the association between the implementation of good practices and suitable interventions during labor and birth, and whether care was a physician or a nurse/nurse-midwife led care. We developed another model to assess the association between the use of obstetric interventions during labor and birth to the personnel responsible for the care of the patient, comparing hospitals with decisions revolving exclusively around a physician to those that also included nurses/nurse-midwives as responsible for vaginal births.

Results

16.2 % of vaginal births were assisted by a nurse/nurse-midwife. Good practices were significantly more frequent in those births assisted by nurses/nurse-midwives (ad lib. diet, mobility during labor, non-pharmacological means of pain relief, and use of a partograph), while some interventions were less frequently used (anesthesia, lithotomy position, uterine fundal pressure and episiotomy). In maternity wards that included a nurse/nurse-midwife in labour and birth care, the incidence of cesarean section was lower.

Conclusions

The results of this study illustrate the potential benefit of collaborative work between physicians and nurses/nurse-midwives in labor and birth care. The adoption of good practices in managing labor and birth could be the first step toward more effective obstetric and midwifery care in Brazil. It may be easier to introduce new approaches rather than to eliminate old ones, which may explain why the reduction of unnecessary interventions during labor and birth was less pronounced than the adoption of new practices.
  相似文献   
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The purpose of this study was to measure the acute effects of pre-exhaustion vs. traditional exercise order on neuromuscular performance and sEMG in trained men. Fourteen young, healthy, resistance trained men (age: 25.5 ± 4.0 years, height: 174.9 ± 4.1 cm, and total body mass: 80.0 ± 11.1 kg) took part of this study. All tests were randomized and counterbalanced for all subjects and experimental conditions. Volunteers attended one session in the laboratory. First, they performed ten repetition maximum (10RM) tests for each exercise (bench press and triceps pushdown) separately. Secondly, they performed all three conditions at 10RM: pre-test (bench press and triceps pushdown, separately), pre-exhaustion (triceps pushdown+bench press, PE) and traditional (bench press+triceps pushdown, TR), and rested 30 minutes between conditions. Results showed that pre-test was significantly greater than PE (p = 0.031) but not different than TR, for total volume load lifted. There was a significant difference between the pre-test and the time-course of lactate measures (p = 0.07). For bench press muscle activity of the pectoralis major, the last repetition was significantly greater than the first repetition (pre-test: p = 0.006, PE: p = 0.016, and TR: p = 0.005). Also, for muscle activity of the triceps brachii, the last repetition was significantly greater than the first repetition (pre-test: p = 0.001, PE: p = 0.005, and TR: p = 0.006). For triceps pushdown, muscle activity of the triceps brachii, the last repetition was significantly greater than the first repetition (pre-test: p = 0.006, PE: p = 0.016, and TR: p = 0.005). For RPE, there were no significant differences between PE and TR (p = 0.15). Our results suggest that exercise order decreases repetitions performed, however, neuromuscular fatigue, lactate, and RPE are not impacted. The lack of difference in total volume load lifted between PE and TR might explain, at least in part, the similar metabolic and perceptual responses.

Key points

  • The effects of different exercise order schemes (e.g. PE and TR) on muscle activity and strength performance indicated that similar responses were observed when comparing these schemes.
  • Strength and conditioning coaches should consider these results when prescribing resistance training programs.
  • The primary target (e.g. muscle group) of the training session should trained first, when fatigue level low, in order to maximize training outcomes.
Key words: Exercise performance, resistance training, biomechanics  相似文献   
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