Routine prenatal screening for congenital heart disease: what can be expected? A decision-analytic approach.

OBJECTIVES: This study assessed the potential impact of fetal ultrasound screening on the number of newborns affected by cardiac anomalies. METHODS: A decision model was developed that included the prevalence and history of congenital heart disease, characteristics of ultrasound, risk of abortion, and attitude toward pregnancy termination. Probabilities were obtained with a literature survey; sensitivity analysis showed their influence on expected outcomes. RESULTS: Presently, screening programs may prevent the birth of approximately 1300 severely affected newborns per million second-trimester pregnancies. However, over 2000 terminations of pregnancy would be required, 750 of which would have ended in intrauterine death or spontaneous abortion. Further, 9900 false-positive screening results would occur, requiring referral. Only the sensitivity of routine screening and attitude toward termination of pregnancy appeared to influence the yield substantially. CONCLUSIONS: The impact of routine screening for congenital heart disease appeared relatively small. Further data may be required to fully assess the utility of prenatal screening.     

维生素与胎儿发育的关系

胎儿在母体宫内需要经过配种、胚胎、胎儿三个阶段,任何影响母胎健康的病因都可以会影响宫内受精卵、胚胎、胎儿发育,严重者甚至胚胎停育、胎死宫内。研究表明各种维生素的缺乏容易诱发人体各种各样的疾病,孕期母体维生素的需要量增加,如果孕期母体维生素摄入不足、补充不够、未得到及时增加或增加过量都会给宫内的胎儿带来害处,影响胎儿器官功能的正常发育,导致胎儿发育不良;有些严重的胎儿畸形是致死性的,孕期要注意筛查及时处理。孕期加强母胎保健,重视优生优育,改善孕妇和儿童营养状况,合理调配膳食和进食并适当补充维生素,了解各种维生素的功效和胎儿发育相关性,对于降低胎儿出生缺陷、防治妇女儿童营养缺乏病、提高人口素质均具有重要实际意义。     

Hydrops fetalis secondary to parvovirus B19 infections

BACKGROUND: Fetal infection by human parvovirus B19 is a common cause of fetal anemia, nonimmune hydrops fetalis, and spontaneous abortion and can result in fetal death. Recent improvements in diagnosing parvovirus infections and the availability of intrauterine transfusion have reduced the overall rate of fetal loss after maternal exposure. METHODS: We report two cases of maternal parvovirus infection with classic findings of hydrops fetalis and review various aspects of parvovirus infection with emphasis on the developing management options in pregnancy. RESULTS AND CONCLUSIONS: Different management led to different results. In the first case there was normal neonatal and infantile development, and in the second case, the fetus died. With accurate laboratory testing, obstetric sonography, and fetal transfusion, the fetal mortality from parvovirus infection has been reduced considerably, and most pregnancies complicated by maternal parvovirus infection result in healthy outcomes.     

Sensitivity and specificity of placental proteins for gestational age screening: An exploratory study

ObjectiveTo examine the possibility that serum or urine concentrations of pregnancy-associated plasma protein A (PAPP-A), a disintegrin and metalloproteinase 12 (ADAM-12), placental growth factor (PlGF), human placental lactogen (HPL), glypican-3, pregnancy specific beta-1-glycoprotein 1 (PSG-1) or prolactin could predict gestational age (GA) >70 days, the currently recommended limit for medical abortion in the United States.Study designIn this exploratory observational study, we collected serum and urine specimens from 245 healthy individuals with singleton intrauterine pregnancies at GA <40 weeks by ultrasound. We assayed the serum specimens for all seven proteins and the urine specimens for PAPP-A and ADAM-12. We used scatterplots and receiver operating characteristic curves to identify a concentration for each protein that would differentiate GAs above and below 70 days.ResultsAll seven proteins showed significant ability to distinguish GAs >70 days from earlier gestations. A PAPP-A concentration ≥5.591 ng/ml provided 100% sensitivity and 90% specificity for identifying GAs >70 days. An ADAM-12 concentration of ≥3.11 ng/ml provided 98.5% sensitivity and 77% specificity for identifying GAs >70 days. Serum concentrations of the other compounds showed less diagnostic discrimination. PAPP-A was not detected in urine, and urinary ADAM-12 concentrations were not useful in identifying GAs above 70 days.ConclusionPAPP-A and ADAM-12 showed considerable promise as bases for a sensitive and specific serum test for identifying pregnancies with GA >70 days. If these results are confirmed by future research, such a test could obviate the need for routine ultrasound before medical abortion.ImplicationsTwo placental proteins, PAPP-A and ADAM-12, showed considerable promise as bases for a serum test for identifying pregnancies with gestational age >70 days. Such a test could be highly useful in screening patients for eligibility for medical abortion.     

Prenatal screening and pregnant women's attitudes toward the abortion of defective fetuses.

We studied the attitudes of 490 pregnant women toward the abortion of defective fetuses. Three hundred of these women were participating in a prenatal screening program for neural tube defects. Although theoretical accounts of the effects of behavior on attitude would suggest that participation in a screening program would affect abortion attitudes, evidence in support of such an association was weak. The overwhelming majority of women, regardless of whether they had participated in the screening program, believed that women are justified in having an abortion in the face of fetal abnormality. There was a sharp increase in the number of screening program participants who said they would have an abortion when the probability of the fetus being affected with a neural tube defect rose from 95 per cent to 100 per cent.     

Expanding medical abortion: can medical abortion be effectively provided without the routine use of ultrasound?

Medical abortion studies have traditionally relied on ultrasound to confirm gestational age, intrauterine location and abortion completion. However, the routine dependence on ultrasound can limit access to safe services for women living in low resource settings that are often most in need of safe abortion care. This review discusses the literature surrounding the safe provision of medical abortion without the routine use of ultrasonography and concludes that clinicians can use the reported last menstrual period (LMP) and physical examination to reasonably estimate gestational age. Completed pregnancy expulsion can be confirmed primarily through history and physical examination with some studies indicating that urine pregnancy tests may also play a limited role. Central to the discussion of whether medical abortion can be provided in most low resource settings without the routine use of ultrasonography is the fact that the mifepristone–misoprostol regimen is a highly effective procedure for pregnancy termination through 63 days' gestation.     

Safety of intrauterine device insertion by trained nurse-midwives in the Sudan

Insertion of intrauterine devices (IUDs) by trained health workers other than physicians is increasing, particularly in developing countries. Twenty nurse-midwives in government service in the Sudan, called health visitors (HVs), were trained to provide intrauterine contraceptives in a research project designed to evaluate the safety of insertion of IUDs by medical personnel who are not physicians. After training, they inserted 763 IUDs. Independent evaluation of 520 clients was conducted by gynecologists who found that only six devices (1.2%) had been incorrectly inserted. Outcomes for clients of the health visitors, with respect to perforations, infections, expulsions, and pregnancies, compared well with those of eight physicians who participated in the study. The research strongly supports the concept of nurse-midwife training for IUD insertion. This would greatly expand the availability of family planning services and would conserve physician time and skills for problem cases.     

What does fetal renal echogenicity mean in intrauterine growth retardation?

AIMS: The object of this study was to investigate the fetal renal and middle cerebral arterial blood flows in patients with normal and hyperechogenic kidneys during the fetal period. MATERIAL AND METHODS: Study group consisted of 82 pregnancies with intrauterine growth retardation. Group included pregnant women from the third trimester. Hyperechogenic medullae were detected in 17 out of 82 pregnancies with intrauterine growth retardation. RESULTS: Fetal renal hyperechogenicity appears to be an indicator of fetal arterial circulatory depression, correlated with pathological changes in the pulsatility index for the fetal renal arteries. The fetal renal arterial blood flow pulsatility index was significantly lower in hyperechogenic cases, while in the middle cerebral artery flow was in the normal range. This may also be an indication of subsequent intrauterine and neonatal complications, such as cesarean section because of fetal distress (47%), treatment in a neonatal intensive care unit (71%) or increased perinatal mortality (12%) in our cases. CONCLUSIONS: Detailed ultrasound of renal parenchyma and Doppler examination of renal and middle cerebral arteries appear to be an useful method in the prenatal diagnosis of reduced renal perfusion and of intrauterine hypoxia so as to detect possible pathological fetal conditions in utero.     

Fetal growth and timing of parturition in humans

Animal studies indicate that either the fetus or the intrauterine environment, both of which set the pattern for fetal growth, may affect the timing of parturition. The authors examined the association between fetal growth and timing of spontaneous onset of labor in humans among low-risk white US women with singleton pregnancies (1987-1991). They restricted the data to pregnancies which had a reliable date of the last menstrual period, normal fetal growth in the first half of pregnancy, and no history of or current pregnancy complications that might have impaired fetal growth (n = 3,360). Subjects received ultrasound examinations at 15-22 and 31-35 weeks' gestation. Fetal growth was adjusted for parity, fetal sex, and maternal prepregnancy weight and height. Results showed that slower or faster fetal growth in the second half of pregnancy resulted in substantially lower or higher birth weight, respectively. However, fetal growth in the second half of pregnancy, even at extremes (2 standard deviations below or above the mean), did not have a meaningful impact on the timing of parturition; neither did fetal growth acceleration or deceleration in late pregnancy. Thus, in low-risk pregnancies where fetal growth is normal in early gestation, fetal growth in the second half of pregnancy does not affect the timing of normal parturition.     

卵巢妊娠43例临床分析

目的:探讨卵巢妊娠的病因、临床特征及诊治特点。方法:回顾性分析1993年7月~2005年12月我院收治的43例卵巢妊娠病例。结果:卵巢妊娠占同期异位妊娠1.81%,绝大多数卵巢妊娠患者(97.67%)社会经济地位低下,有人流(65.12%)及妇科病史(60.47%),37.21%放置宫内节育器。卵巢妊娠最主要症状是腹痛(93.02%),仅74.42%有停经史,37.21%阴道出血。所有患者无1例术前确诊,均手术治疗,其中5例行腹腔镜手术。结论:卵巢妊娠发生率呈上升趋势,与人流、妇科疾病及放置宫内节育器有关。开展以社区为基础的综合健康教育来提高妇女健康意识十分迫切。因临床表现不典型,术前很难确诊,应充分结合血β-HCG及阴道B超以提高术前诊断率。治疗应以手术为主。腹腔镜手术安全、有效,值得推广。     

多胎妊娠减胎术的临床应用

目的:分析多胎妊娠早期减胎术的可行性、安全性及对妊娠的影响,决定合适的手术时机、手术方法。方法:多胎妊娠孕妇,于孕早期在腹部B超引导下,将穿刺针选择性进入1～2个胚胎的心管搏动处注射氯化钾,或经阴道B超引导下,将穿刺针选择性进入胚胎心管搏动处,反复抽吸至胎心消失或负压吸出胚胎。结果:84例中78例经阴道减胎术单次成功,6例减胎2次成功。5例经腹胎心注射氯化钾减胎术,60例经阴道抽吸胚胎法,19例经阴道机械破坏法。26例足月剖宫产,10例足月顺产,24例早产,6例早期流产,4例晚期流产,无1例因感染而于术后第3～7天流产,现14例继续妊娠。59例减胎术后为双胎妊娠,25例减胎术后为单胎妊娠。多胎妊娠的减胎术成功率88.1%,总流产率11.9%。已分娩的112个新生儿均健康。结论:超声引导下经阴道多胎妊娠早期选择性减胎术是安全、有效和简便的治疗方法,选择妊娠7～8周经阴道抽吸胚胎法进行效果较好。     

Maternal serum alpha-fetoprotein screening: benefits, risks, and costs

Based upon previously published reports, the benefits and risks of screening a hypothetical population of 10,000 women are analyzed, and the cost benefit of maternal serum alpha-fetoprotein screening is reviewed. Five hundred women would have an initially elevated serum alpha-fetoprotein and experience moderately severe anxiety until further tests are completed. One hundred fifty pregnancies would undergo amniocentesis with approximately one spontaneous abortion resulting from the procedure. Fifty sets of twins, 86 pregnancies with underestimated gestational age, and 50 pregnancies at risk for low birthweight or fetal death would be identified. All four anencephalics and three of four fetuses with spina bifida would be detected. The benefits to pregnant women of prenatal screening for neural tube defects exceed the risks. At the present incidence of neural tube defects, the cost of prenatal screening to society approximately equals the economic savings. If the incidence of neural tube defects continues to fall, the benefits, risks, and costs will have to be reevaluated. There are insufficient data to determine adequately the benefits, risks, and costs of the screening for Down's syndrome with maternal serum alpha-fetoprotein, and such screening should be discouraged.     

Uterine cavity assessment prior to IVF

Approximately 15% of couples are affected with subfertility, of which up to 20% remain unexplained. Uterine cavity abnormalities can be a contributing cause of subfertility and recurrent implantation failure. Uterine cavity assessment has been suggested as a routine investigation in the evaluation of subfertile women. Traditionally, hysterosalpingography has been the most commonly used technique in the evaluation of infertility. Transvaginal ultrasound scan allows visualization of the endometrial lining and cavity, and has been used as a screening test for the assessment of uterine cavity. Abnormal uterine findings on a baseline scan can be further evaluated with saline hysterosonography, which is highly sensitive and specific in identifying intrauterine abnormalities. Hysteroscopy is considered as the definitive diagnostic tool to evaluate any abnormality suspected on hysterosalpingography, transvaginal ultrasound scan or saline hysterosonography during routine investigation of infertile patients. Minimally invasive hysteroscopes have minimized the pain experienced by patients during the procedure and made it feasible to use hysteroscopy as a routine outpatient examination. Following recurrent IVF failure there is some evidence of benefit from hysteroscopy in increasing the chance of pregnancy in the subsequent IVF cycle, both in those with abnormal and normal hysteroscopic findings. Various possible mechanisms have been proposed for this beneficial effect, but more randomized controlled trials are needed before its routine use in the general subfertile population can be recommended.     

Maternal serum alpha-fetoprotein screening: a cost-benefit analysis.

The prenatal detection of fetal neural tube defects (NTD) is now possible by means of a multi-tiered program utilizing maternal serum alpha-fetoprotein (MSAFP) screening coupled with ultrasonography and amniocentesis where indicated. This paper considers the economic consequences of screening for fetal NTD a theoretical cohort of 100,000 pregnant women at risk of having an affected fetus who would elect to terminate their pregnancies if an affected fetus were found. The cost of the program was balanced against the benefits of the program, such as the averted costs of institutionalization, medical care, and the like. The total cost of the program to screen 100,000 such women was calculated to be $2,047,780, or slightly over $20 per woman screened, while the total economic benefits exceeded $4,000,000.     

Randomized comparison of levonorgestrel- and copper-releasing intrauterine systems immediately after abortion,with 5 years' follow-up

Women who seek an abortion are motivated to use contraceptive methods afterwards. Because the return of fertility after abortion is immediate, there is a need for effective and safe contraception promptly after the termination of pregnancy. A randomized trial of Mirena and NovaT intrauterine contraceptive devices inserted at the time of elective termination of pregnancy, duration no more than 12 weeks, is reported here. Women were randomized 2:1 resulting in 305 subjects with Mirena and 133 with NovaT as a segment of a larger study of 3000 women. In the Mirena group, two pregnancies at year 4 resulted in a final gross rate of 0.8 at 5 years, which was significantly (p < 0.0004) lower than the corresponding rate of 9.5 with NovaT. Terminations because of expulsion, bleeding problems, pain, pelvic inflammatory disease and other medical reasons were less common in the Mirena group, but not significantly different. The cumulative expulsion gross rate for NovaT at 5 years was 15.4 and for Mirena it was 10.5. Termination rates because of amenorrhea were low in both groups. It is concluded that both devices were well tolerated. Mirena was more effective and the rate of adverse events was lower than with NovaT. Special attention should be paid to the insertion procedure when carried out at the time of abortion.     

胎儿单脐动脉的研究进展

正常胎儿的脐带有2条脐动脉,而单脐动脉(SUA)胎儿的脐带中仅为1条脐动脉,系脐带发育及结构异常。SUA的诊断主要依靠产前超声检查和产后胎盘、脐带大体检查及其病理学检查。目前,SUA的发生机制尚未阐明。越来越多的研究结果显示,SUA是胎儿先天畸形、染色体核型异常、早产及低出生体质量的软标记,SUA亦可能引起胎儿宫内生长受限及出生后生长发育不良等不良结局。笔者拟就SUA的概念及分类、诊断、发生机制、与之相关的胎儿畸形和染色体核型异常等综述如下。     

Changing tactics in the abortion argument: does a fetus feel pain?

The 30th anniversary of the passing of the abortion law in England sparked off yet another skirmish in the continuing struggle. Not only the Catholic Church but also anti-lobby groups have protested against the abortion law. Anti-lobby groups consider abortion as an evil that must be fought. To further explain their point, the anti-lobby groups used the conclusions on pediatric anesthetic practice to change their tactics in combating the abortion issue from the emotional point of view to the apparently rational. A group of pediatricians, anesthetists, bioethicists and neuroanatomists has considered the problem of when the fetus may first be able to feel pain. They have decided that the fetus cannot feel pain before the 26th week and recommended that the fetus be given an anesthetic for any abortion later than the 24th week. The anti-lobby groups say that this view limits the perception of pain to the cerebral cortex and that the thalamus is well enough developed by the 10th week for the growing embryo to feel the pain. However, as to the question of fetal pain, one can never know whether fetuses feel pain, because they can never tell.     

超声筛查在胎儿颅脑畸形的应用及研究

目的探讨分析超声筛查在胎儿颅脑畸形的应用价值,研究超声筛查的作用。方法选取该院2011年1月1日—2012年12月31日间进行超声筛查胎儿颅脑畸形的孕妇5430例,采用多切面序贯扫查法对胎儿颅脑进行筛查,对于超声诊断颅脑严重畸形的胎儿,进行中止妊娠。结果超声筛查检出19例胎儿颅脑畸形,经产后证实检出率为100%(6/6)。在进行超声筛查胎儿颅脑畸形的过程中,检出心脏畸形18例,唇腭裂12例,羊膜束带综合征1例,先天性膈疝3例,先天性肺囊腺瘤2例,四肢短小3例。结论超声筛查在胎儿颅脑畸形的应用价值巨大,对胎儿颅脑畸形的检出率高,同时可以检出胎儿自身患有的畸形,为临床提供有价值的信息。     

Tobacco smoke exposure and pregnancy outcome among working women. A prospective study at prenatal care centers in Orebro County, Sweden

Among 4,687 women undergoing prenatal care in Orebro County, Sweden, from October 1980 to June 1983, 678 nonsmokers reported passive exposure to tobacco smoke. Of these women, 267 had been passively exposed at work, and the risk ratio (RR) for intrauterine death (spontaneous abortion or stillbirth) among these pregnancies was increased to 1.53 (95% confidence interval (CI) 0.98-2.38) compared with pregnancies of unexposed working women. This could not be explained by age, previous spontaneous abortion, educational level, planning of pregnancy, or alcohol use. The effect was confined to first-trimester fetal loss (adjusted RR = 2.16, 95% CI 1.23-3.81), while active smoking was associated with intrauterine death after the first trimester. Passive exposure in the workplace was weakly associated with preterm birth (less than 37 weeks) but not with low birth weight (less than 2,500 g) among full-term livebirths. Active smoking clearly increased the risk of both of these outcomes. However, passive exposure in the home only did not seem to affect pregnancy outcome. The lack of quantitative exposure data points to the need for more research before passive exposure to tobacco smoke can be regarded as an established hazard to fetal development and survival.     

宫腔镜联合腹部B超处理难取宫内节育器的临床分析

目的探讨应用宫腔镜联合腹部B超处理难取的宫内节育器的临床价值。方法选择常规方法取器失败1～3次的病例78例，在官腔镜联合腹部B超监测下取器，观察疗效及并发症。结果所有患者一次性取器成功，成功率100％，无并发症。结论宫腔镜下联合腹部B超监测处理难取宫内节育器的方法是成功的。