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991.
992.
Objective: To compare the obstetrical and neonatal outcomes of late adolescent (LA) and adult pregnancies.

Methods: Between January 2012 and December 2012, a total of 313 late adolescent pregnant aged between 16 and 19 years and 418 adult pregnant women aged between 20 and 35 years having given birth in our maternity service were enrolled into this case–control study. The demographic and clinical data were reviewed from hospital database and patients’ medical records.

Results: The incidence of preterm birth (PB) in the LA group was significantly higher than in the adult group (p?=?0.001), while the incidence of gestational diabetes mellitus was significantly lower (p?=?0.001). The mean birth weight and the rate of delivered macrosomic fetuses in the study group were lower than in the control group (p?=?0.03). The LA group had significantly higher rate of vaginal delivery when compared to the adult group (p?=?0.001). Both the rate of pregnancy induced hypertensive disorders and postpartum hemorrhage were not statistically different between the two groups (p?=?0.31; p?=?0.38, respectively). The LA group had lower rate of stillbirth when compared to the adult group; however, the difference was statistically insignificant (0.3% versus 1.2%) (p?=?0.24).

Conclusions: The LA pregnancy should be closely followed up during their antenatal care period due to the significantly higher rate of PB.  相似文献   
993.
Objective: The objective was to evaluate and compare the whole blood nitrite concentration in the three trimesters of pregnancy. Additionally, we investigate whether there is any relation between nitrite concentrations and Doppler ultrasound analysis of some maternal and fetal vessels.

Methods: Thirty-three healthy pregnant women were examined at the first (11–14 weeks), second (20–24 weeks) and third trimester (34–36 weeks) of pregnancy. In the three exams, we determined the maternal whole blood nitrite concentration and uterine arteries Doppler analysis to determine pulsatility index (PI), and resistance index (RI). In the second and third trimester we also performed fetal umbilical and middle cerebral arteries PI and RI. We compared the concentrations of nitrite in three trimesters and correlated with Doppler parameters.

Results: No difference was observed in the whole blood nitrite concentrations across trimesters: 151.70?±?77.90?nmol/ml, 142.10?±?73.50?nmol/ml and 147.10?±?87.30?nmol/ml; first, second and third trimesters, respectively. We found no difference in correlation between whole blood nitrite concentration and Doppler parameters from the evaluated vessels.

Conclusions: In healthy pregnant women, the nitrite concentrations did not change across gestational trimesters and there was also no strong correlation with Doppler impedance indices from maternal uterine arteries and fetal umbilical and middle cerebral arteries.  相似文献   
994.
Objective: Pregnancies among morbidly obese women are associated with serious adverse maternal and neonatal outcomes. Our study objective is to evaluate the effect of bariatric surgery on obstetrical outcomes.

Methods: We carried out a retrospective cohort study using the healthcare cost and utilization project – Nationwide Inpatient Sample from 2003 to 2011 comparing outcome of births among women who had undergone bariatric surgery with births among women with morbid obesity. Logistic regression was used to estimate the adjusted effect of bariatric surgery on maternal and newborn outcomes.

Results: There were 8 475 831 births during the study period (221 580 (2.6%) in morbidly obese women and 9587 (0.1%) in women with bariatric surgery). Women with bariatric surgery were more likely to be Caucasian and ≥35 years old as compared with morbidly obese women. As compared with women with morbid obesity, women with bariatric surgery had lower rates of hypertensive disorders, premature rupture of membrane, chorioamnionitis, cesarean delivery, instrumental delivery, postpartum hemorrhage, and postpartum infection. Induction of labor, postpartum blood transfusions, venous thromboembolisms, and intrauterine fetal growth restriction were more common in the bariatric surgery group. There were no differences observed in preterm births, fetal deaths, or reported congenital anomalies.

Conclusion: In general, women who undergo bariatric surgery have improved pregnancy outcomes as compared with morbidly obese women. However, the bariatric surgery group was more likely to have venous thromboembolisms, to require a blood transfusion, to have their labor induced and to experience fetal growth restriction.  相似文献   
995.
Objective: We sought to assess the association between maternal height and the risk of preterm birth, fetal growth restriction and mode of delivery in twin gestations.

Study design: Cohort study of patients with twin pregnancies delivered from 2005 to 2014. We compared pregnancy outcomes between patients of short stature?≤159?cm to those of normal stature?≥160?cm. Patients with monoamniotic twins and major fetal anomalies were excluded. Pearson’s correlation, Chi-square and Student’s t-test were used as appropriate.

Results: Six hundred and sixty-six patients were included, 159 (23.9%) of whom had short stature (mean height 155.8?±?2.5?cm) and 507 (76.1%) of whom had normal stature (mean height 167.2?±?5.5?cm). There were no differences in outcomes between the groups in regards to preterm birth, gestational age (GA) at delivery, birth weight of either twin, preeclampsia, gestational diabetes or cesarean section rate. Results were similar when the groups were stratified by parity. As a continuous variable, maternal height did not correlate with GA at delivery (p=?0.388), cesarean delivery (p?=?0.522) nor the birth weight of the larger (p?=?0.206) or smaller (p?=?0.307) twin.

Conclusion: In twin pregnancies, maternal short stature is not associated with preterm birth, fetal growth restriction or cesarean section rate. This suggests that although anthropometric measurements have long been used to counsel patients in regards to outcomes, patients of short stature should be reassured that their height does not appear to lead to adverse twin pregnancy outcomes.  相似文献   
996.
Objective: To compare cesarean complication rates between women with body mass index (BMI) 40–49.9?kg/m2 and BMI?≥?50?kg/m2 and associations with surgical techniques.

Methods: This retrospective cohort study from 2009 to 2014 included women who underwent cesarean with delivery BMI?≥?50 and an equal number with BMI 40–49.9. Wound infections and/or separations were compared. We also examined wound complication rates between skin closure techniques and self-retaining retractor use.

Results: Among 498 patients (249 with BMI?≥?50 and 249 with BMI 40–49.9) there were no differences in estimated blood loss >1000?mL, blood transfusion, deep vein thrombosis or endometritis. Among those with outpatient follow-up (144 with BMI?≥?50 and 162 with BMI 40–49.9), those with BMI?≥?50 had a significantly higher rate of wound separations (p?=?0.01) but not infections. There were no differences in wound complication rates between skin closure techniques or self-retaining retractor use, though the study was not powered for these comparisons.

Conclusion: Wound complications, particularly separations, increase with BMI?≥?50 compared to a lesser degree of morbid obesity. Skin closure techniques and self-retaining retractor use were not associated with cesarean wound complications in patients with morbid obesity.  相似文献   
997.
目的:探讨双胎妊娠和三胎妊娠地中海贫血的产前基因诊断情况。方法:对27例双胎妊娠和三胎妊娠患者进行绒毛膜穿刺或羊膜囊穿刺胎儿取样,采取裂隙聚合酶链反应以及聚合酶链反应结合反向点杂交方法进行产前基因诊断。结果:在进行α地中海贫血产前基因诊断的20例双胎妊娠及1例三胎妊娠中,共对43个胎儿进行取材,共检测出6例Bart's水肿胎,3例血红蛋白H病。在进行β地中海贫血产前基因诊断的6例双胎妊娠中,共对9个胎儿进行取材,共检测到3例中重型β地中海贫血。结论:地中海贫血的多胎妊娠孕妇产前基因诊断能较有效检出Bart's水肿胎和中重型β地中海贫血患儿,可预防重型地中海贫血患儿的出生。  相似文献   
998.
目的:探讨复发性流产(RPL)患者NK细胞毒性和子宫动脉血流灌注对妊娠结局的影响。方法:回顾分析162例RPL患者的临床资料,根据妊娠结局分为流产组(n=30)和分娩组(n=132),比较两组的NK细胞毒性和子宫动脉血流阻力指数(U-RI)变化。结果:流产组的孕前NK细胞毒性高于分娩组,差异有统计学意义(P=0.02),两组的孕前U-RI比较差异无统计学意义(P=0.12);早孕期流产组各孕周的NK细胞毒性均高于分娩组,但差异无统计学意义(P0.05)。U-RI在早孕期较孕前明显降低(P0.001),且分娩组U-RI随孕周增加逐渐降低;与分娩组相比,孕7、8、9周时流产组的URI明显升高,差异有统计学意义(P=0.008,P=0.001,P=0.043)。结论:孕前NK细胞毒性增高,孕7~9周子宫动脉血流灌注量下降的患者再次自然流产风险增高,两者为独立危险因素。  相似文献   
999.
正乙型肝炎是由乙型肝炎病毒(hepatitis B,HBV)引起的一种严重危害人类健康的疾病,全世界的感染人数超过了24 000万。在美国,妊娠妇女群体中的HBV感染率约为0.7%~0.9%~([1-2])。宫内和围产期垂直传播是全球HBV传播的重要组成部分。研究表明,35%~50%的HBV携带者是由于围产期接触受感染的血液及其污染物而受到感染~([1])。预防受感染孕妇的HBV垂直传播给胎儿,对减少  相似文献   
1000.
A persistent finding is that assisted reproductive technology (ART) is associated with compromised birth outcomes, including higher risks for prematurity, low birthweight, and congenital malformations, even among singletons. Over the past decade, our research group, the Massachusetts Outcome Study of Assisted Reproductive Technology (MOSART), has evaluated pregnancy and birth outcomes among three groups of women, those women treated with ART, those with indicators of subfertility but without ART treatment, and fertile women. We have also explored the influence of infertility-related diagnoses on outcomes for women and infants. Over the course of our research, we have changed our perspective from an original focus on ART treatment parameters as the primary cause of excess morbidity to one centered instead on the underlying infertility-related diagnoses. This paper summarizes the research findings from our group that support this change in focus for infertility-based research from a primary emphasis on ART treatment to greater attention to the contribution of preexisting pathology underlying the infertility and suggests directions for future analyses.  相似文献   
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