Prenatal lead exposure in relation to gestational age and birth weight: A review of epidemiologic studies

Although the adverse effect on pregnancy outcomes at high levels of lead exposure in the workplace has been recognized for years, there is uncertainty regarding the impact of exposure at the lower community exposure levels commonly encountered today. This review summarizes the epidemiologic literature and discusses pertinent methodologic issues and possible sources of interstudy variation. The authors conclude that prenatal lead exposure is unlikely to increase the risk of premature membrane rupture but does appear to increase the risk of preterm delivery. Whether prenatal lead exposure decreases gestational age in terms of infants is unclear. Prenatal lead exposure also appears to be associated with reduced birth weight, but results vary in relation to study design and degree of control for confounding. Adjustment for gestational age, a possible confounder of the birth weight-lead exposure association, did not yield clearer results.     

Outcomes of planned home birth: an integrative review

Current evidence indicates the critical importance of several factors that contribute to improved perinatal outcomes: a facilitating environment at the place of birth, skilled birth attendance, and the continuum of perinatal care for women and newborns. This level of care is often referred to as "first-level" care, and is most readily provided in birthing centers and primary level health facilities. However, there is a body of evidence that has been compiled over the past several decades that addresses the safety of planned home birth, under circumstances that emulate these elements of "first-level" care. These studies demonstrate a remarkable consistency in the generally favorable results of maternal and neonatal outcomes, both over time and among diverse population groups. These outcomes are also favorable when viewed in comparison to various reference groups (birth center births, planned hospital births, and vital statistics). These data should influence policy in support of planned home birth, including policy that endorses building or sustaining a home birth infrastructure in parallel to the efforts to build capacity for facility-based birth. Such public policy would also be in keeping with the fundamental right of women to have choice in childbirth, particularly when options are equally good.     

Length of the third stage of labor at term pregnancies is shorter if placenta is located at fundus: prospective study

AIM: To investigate how the location of the placenta at term pregnancies affects the duration of the third stage of labor and to discuss the possible mechanisms affecting the duration of the third stage. We believe that this is the first prospective study comparing the duration of the third stage of labor according to placental location. METHODS: The placental implantation was determined as anterior (n = 78), posterior (n = 59), or fundal (n = 64) by ultrasound, in 201 women with singleton pregnancies. After delivery of the newborn, oxytocin infusion was routinely given. Duration of the third stage of labor was compared by anova. P < 0.05 was determined as significant. RESULTS: The duration of the third stage of labor was 10.36 +/- 5.94 min, 10.44 +/- 5.35 min, and 8.12 +/- 4.25 min with placentas located anteriorly, posteriorly, and fundal, respectively. The length of the third stage was significantly shorter in the fundal placenta group. CONCLUSION: In this study, the length of the third stage of labor was approximately 2 min shorter with placentas located at the fundus compared to the other two groups. The mechanism responsible for shorter duration may be the bipolar separation of fundal placentas in contrast to usual unipolar down-up separation of anterior or posterior placentas. Another contributing factor may be the use of oxytocin infusion for the management of the third stage, however this should be investigated by further studies by using real time ultrasonography.     

A review of factors associated with dystocia and cesarean section in nulliparous women

The primary indication for cesarean section in nulliparous women continues to be clinical diagnoses that fall under the rubric of dystocia. These diagnoses account for approximately two-thirds of all cesareans experienced by otherwise healthy nulliparous women. Contemporary research evidence suggests that this clinical phenomenon is complex and multifactorial. This review explores factors associated with the phenomenon of dystocia in the context of a conceptual model that considers women's physical and psychological characteristics, fetal factors, intrapartum care and interventions, assessments and clinical decision-making of health care providers, the sociopolitical environment, and the social and physical environment of childbirth. Clinical recommendations include emphasis on the maintenance of normal weight and weight gain during pregnancy, delaying the admission of nulliparous women to the hospital until active labor is established, avoiding elective induction for nulliparous women, keeping women well-hydrated and well-fed during labor, providing high-quality supportive care during labor, staying the course with effective treatment when dystocia is encountered, and a renewed emphasis on the psychobehavioral preparation of nulliparous women for the realities of labor.     

Risk factors for anal sphincter tears: the importance of maternal position at birth

Objective  To assess the role of birth position in the occurrence of anal sphincter tears (AST).
Design  Observational cohort study.
Setting  South Hospital in Stockholm, a teaching hospital with around 5700 births per year.
Population  Among all 19 151 women who gave birth at the South Hospital during the study period 2002–05, 12 782 women met the inclusion criteria of noninstrumental, vaginal deliveries.
Methods  Data on birth position and other obstetric factors were analysed in relation to occurrence of AST.
Main outcome measure  Third- and fourth-degree AST.
Results  AST occurred in 449 women (3.5%). The trauma was more frequent in primiparous (5.8%) than in multiparous women (1.7%). The highest proportion of AST was found among women who gave birth in lithotomy position (6.9%), followed by squatting position (6.4%). Logistic regression analyses showed that lithotomy (adjusted OR 2.02, 95% CI 1.58–2.59) and squatting positions (adjusted OR 2.05, 95% CI 1.09–3.82) were associated with a significantly increased risk for AST. Other major risk factors for anal sphincter trauma were primiparity (adjusted OR 3.29, 95% CI 2.55–4.25), prolonged second stage of labour >1 hour (adjusted OR 1.52, 95% CI 1.11–2.10), infant birthweight more than 4 kg (adjusted OR 2.12, 95% CI 1.64–2.72) and large infant head circumference (adjusted OR 1.57, 95% CI 1.23–1.99).
Conclusion  Lithotomy and squatting position at birth were associated with an increased risk for AST also after control for other risk factors.     

Evaluation of pregnant women with scarred uterus in a low resource setting

AIM: Management of post cesarean pregnancy continues to be a dilemma. The present study was undertaken to evaluate the outcome of such pregnancies in a resource constrained setting so that an appropriate management protocol can be decided. METHODS: An observational study was conducted in the Department Of Obstetrics And Gynecology, King George's Medical University, Lucknow, India. The outcome of all of the women admitted with pregnancy with a previous cesarean section was noted. RESULTS: A total number of 447 women with a post cesarean pregnancy underwent delivery. These comprised 13.7% of total deliveries over the same period. 124 women (27.7%) had successful vaginal delivery while 323 (72.3%) had a repeat cesarean section. Maternal morbidity and perinatal mortality were both significantly higher in the vaginal delivery group (P = 0.00211 and P = 0.0426, respectively). CONCLUSIONS: Vaginal birth after cesarean (VBAC) is associated with higher maternal morbidity and perinatal mortality. Therefore the decision for VBAC must be taken only after proper consideration and counseling of the couple.     

复方保元煎对绝经后CHD患者脂代谢和血流变影响的研究

目的:研究复方保元煎对绝经后冠心病(CHD)患者脂代谢、血流变的影响。方法:观察180例患者,随机分为治疗组102例,对照组78例。治疗组采用中药复方保元煎治疗,对照组采用维尼安治疗,分别于治疗前后测定脂代谢、血流变指标。结果:治疗后两组脂代谢、血流变指标均有不同程度的改变。治疗组在降低总胆固醇(TC)、甘油三酯(TG),低密度脂蛋白(LDL-C)、载脂蛋白B(apoB)、血流变指标优于对照组(P<0.05或P<0.01)。结论:复方保元煎能改变血脂代谢、调节血黏度,对预防和逆转绝经后的CHD的发生和发展有积极的治疗作用。     

小剂量米非司酮用于紧急避孕临床观察

目的 观察一次性小剂量米非司酮用于紧急避孕的效果。方法征集无保护性交或避孕失败后72小时内就诊并符合条件的健康妇女100例，单次口服米非司酮10mg。结果失败1例，按照Dixon方法计算，避孕有效率为89．55％；受试的月经周期无明显改变且未出现明显副作用。结论小剂量米非司酮单次口服用于紧急避孕简单、有效、安全。     

含服米索前列醇预防选择性剖宫产产后出血

目的：探讨舌下含服米索前列醇预防剖宫产产后出血的效果。方法：将妊娠晚期单胎选择性剖宫产者200例随机分为两组,研究组110例，在第二产程末胎头娩出后舌下含服米索400μg，对照组90例，在胎儿娩出后静脉注射催产素20IU，观察产后2h出血量和用米索前后血压及用药后出现的副作用，结果：产后2h内的出血量，研究组与对照组分别为174．43ml和219.73ml，二组比较有显著性差异（P＜0．01），用米索前后血压比较，二组无显著性差异（P＞0．05），结论：舌下含服前列醇促进子宫收缩作用强于催产素，能减少产后出血，也适用于某些与血管变化有关的高危孕产妇，预防产后出血。     

恩丹西酮与地塞米松预防性治疗腹腔镜胆囊切除术后恶心呕吐的临床观察

目的：探讨恩丹西酮与地塞米松预防性治疗腹腔镜胆囊切除术后恶心呕吐的比较。方法：89例择期腹腔镜胆囊切除术者随机为恩丹西酮、地塞米松和生理盐水组。麻醉诱导及维持方法相同，诱导时三组分别注射恩丹西酮8mg、地塞米松10mg及生理盐水5ml。术后观察病人24h恶心、呕吐情况。结果：恩丹西酮和地塞米松组与生理盐水组相比＊P＜0．01，恩丹西酮组与地塞米松组相比＃P＞0．05。结论：恩丹西酮与地塞米松均能有效防治腹腔镜胆囊切除术后恶心呕吐，但恩丹西酮价格昂贵，地塞米松则比较低廉，有推广使用价值。