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1.
We conducted a retrospective cohort study to assess the risk of amniocentesis in twin pregnancy for adverse outcomes. The study base consisted of women who had an amniocentesis performed during twin pregnancy and a comparison representative sample of women who carried a twin pregnancy, but did not have invasive prenatal diagnosis. The 227 women in each of the exposed and non-exposed groups were residents of the state of New South Wales, Australia, over the period 1980-92, and were matched on maternal age and period of the infant's birth. Nearly 10% of twin pregnancies among the women having an amniocentesis were affected by a stillbirth, and the stillbirth rate among exposed fetuses (5.3%) was nearly twice as high as among non-exposed fetuses (3.1%). After adjustment for confounding and excluding abnormalities, there was a non-significant elevated relative risk of stillbirth after exposure to amniocentesis. The analysis by type of amniocentesis (with and without methylene blue dye) was limited by small numbers, but the burden of risk was primarily among women who had dye exposure during amniocentesis (relative risk = 3.64, 95% confidence interval = 1.15, 11.48). This increase remained after adjusting for confounding, although the confidence interval was wide. In conclusion, we were unable to establish with certainty whether an increased risk of stillbirth could be ruled out among women who had any type of amniocentesis in twin pregnancy.  相似文献   

2.
OBJECTIVE: To determine the maternal age at which twin gestations have a risk of fetal aneuploidy comparable to that of singleton pregnancies at maternal age 35, accounting for variation in dizygotic twinning rates by maternal age and race. METHODS: Known aneuploidy risks and rates of dizygotic twinning by maternal age and race were used to calculate the risk of fetal aneuploidy at term and in the second trimester by maternal age and race in twin gestations, using previously published calculations. RESULTS: The risk of at least one aneuploid twin at term is 1/193 at maternal age 31 for both white and African-American women, which is comparable to the risk of 1/192 for an aneuploid singleton term pregnancy at maternal age 35. The risk of at least one aneuploid twin at amniocentesis at maternal age 31 is 1/190 for white and 1/187 for African-American women, which is slightly lower than the rate in singletons of 1/135. CONCLUSION: Invasive prenatal diagnosis for detection of fetal aneuploidy should be offered to all women with twin gestations at age 31, regardless of race.  相似文献   

3.
Second trimester maternal serum screening for fetal Down's syndrome (DS), using the AFP (alpha-fetoprotein), hCG (human chorionic gonadotrophin) and uE3 (unconjugated oestriol) triple test, is as well documented procedure associated with a DS-detection rate of about 70 per cent, for an amniocentesis rate of about 7 per cent. The triple test is relatively little used in the Nordic countries, though its wider use would result in more efficient diagnosis of DS and various fetal malformtions. The maternal age indication currently used leaves gravidae under 35 years of age without prenatal diagnostics, although it is in just this age group that the majority (70 per cent) of cases of fetal DS occur. In Denmark, where 12 per cent of gravidae undergo invasive diagnostic procedures, the proportion of induced abortions due to the procedures is far too high, in relation to the DS detection rates obtained. Maternal serum screening yields a much better ratio between the risk of abortion after amniocentesis and the likelihood of DS detection than does maternal age alone. Maternal serum screening at 7-14 weeks of gestation, using pregnancy-associated plasma protein A and free hCG beta subunit concentrations, will become available within the next few years, thus reducing the incidence of some of the psychological and technical problems associated with second trimester screening, especially that of third trimester abortion. Irrespective of whether it is performed in the first or the second trimester, maternal serum screening will be the cornerstone of prenatal DS diagnosis in the future.  相似文献   

4.
OBJECTIVE: To assess pregnancies and conceptus after artificial insemination (AID) or IVF with frozen semen donor (IVF-D) on sufficiently large study population in order to distinguished minor variations. STUDY DESIGN: From 1987 to 1994, all pregnancies obtained after AID or IVF-D were registered prospectively in the French CECOS Federation data base. Different factors were recorded for this study: first menarche age of the recipient women, cycle length, insemination date in the conception cycle, maternal age at delivery, hormonal treatments, donor age, sperm conservation length and follow up of the pregnancy: miscarriage, tubal pregnancy, time at delivery, sex of the foetus, weight, malformation. RESULTS: 21,597 pregnancies obtained after AID and 3381 after IVF-D were registered. 2% were lost to follow up. Foetal loss rate is 18% after AID and 21.5% after IVF-D (p < 0.001). The tubal pregnancy rate is 0.9% after AID and 1.7% after IVF-D (p < 0.0001). 18,128 children were born after AID and 3313 after IVF-D. After AID, the twin pregnancy rate is 6.9% and the multiple pregnancy (> or = 3 foetus) rate is 0.7%. After IVF-D, these rates are 24.8% and 4.2% respectively (p < 0.0001). After AID the mean weight at delivery, sex ratio, premature rate, intra uterine growth retardation rate are not different from national rates published in 1995. The foetus malformation rate (including medical abortions) is 1.9% after AID and 2.7% after IVF-D (p < 0.009). After AID the trisomy 21 rate increases with the mother age but also with the donors age if the maternal age is equal. The birth defects rate is not different from those registered in Paris, Strasbourg and Marseille. The birth defects rate observed after IVF-D is not different from the rate observed after IVF with husband semen. (2.74% versus 2.99%; p = 0.16). CONCLUSION: After AID the miscarriage and tubal pregnancy rate, the children's weight, the premature rate is not different from that of the general French population. Sex ratio is normal as is the global malformation rate. The multiple pregnancy rate (x 7 for twin and by 10 for multiple pregnancies more than 3 foetus) is high, showing the influence of ovulation induction treatment. The birth chromosomal abnormalities rate is normal and correlated not only to the mother's age but also to the donor's age. This result without clear biological explanation will require further verification in a greater population. Practically speaking, these observations encourages lowering the age limit for semen donors less than 45 years. IVF-D practice instead of AID doubles the tubal pregnancy rate (0.9% versus 1.7% and increases the twin pregnancy rate by 2.5% and the multiple pregnancy (> or = 3 fetus) rate by 3. It is necessary to promote good practice for AID for which the pregnancy rate is very different from one centre to another within the centres with AID low results a too high rate of IVF-D. Finally we can say that pregnancies from IVF-D or IVF with husband semen are not significantly different. In other words pregnancy outcome is not changed after sperm cryopreservation.  相似文献   

5.
BACKGROUND: In 1968 the first antenatal diagnosis of Down's syndrome was made and screening on the basis of selecting women of advanced maternal age for amniocentesis was gradually introduced into medical practice. In 1983 it was shown that low maternal serum alpha fetoprotein (AFP) was associated with Down's syndrome. Later, raised maternal serum human chorionic gonadotrophin (hCG), and low unconjugated oestriol (uE3) were found to be markers of Down's syndrome. In 1988 the three biochemical markers were used together with maternal age as a method of screening, and this has been widely adopted. PRINCIPLES OF ANTENATAL SCREENING FOR DOWN'S SYNDROME: Methods of screening need to be fully evaluated before being introduced into routine clinical practice. This included choosing markers for which there is sufficient scientific evidence of efficacy, quantifying performance in terms of detection and false positive rates, and establishing methods of monitoring performance. Screening needs to be provided as an integrated service, coordinating and managing the separate aspects of the screening process. SERUM MARKERS AT 15-22 WEEKS OF PREGNANCY: A large number of serum markers have been found to be associated with Down's syndrome between 15 and 22 weeks of pregnancy. The principal markers are AFP, hCG or its individual subunits (free alpha- and free beta-hCG), uE3, and inhibin A. Screening performance varies according to the choice of markers used and whether ultrasound is used to estimate gestational age (table 1). When an ultrasound scan is used to estimate gestational age the detection rate for a 5% false positive rate is estimated to be 59% using the double test (AFP and hCG), 69% using the triple test (AFP, hCG, uE3), and 76% using the quadruple test (AFP, hCG, uE3, inhibin A), all in combination with maternal age. Other factors that can usefully be taken into account in screening are maternal weight, the presence of insulin dependent diabetes mellitus, multiple pregnancy, ethnic origin, previous Down's syndrome pregnancy, and whether the test is the first one in a pregnancy or a repeat. Factors such as parity and smoking are associated with one or more of the serum markers, but the effect is too small to justify adjusting for these factors in interpreting a screening test. URINARY MARKERS AND FETAL CELLS IN MATERNAL BLOOD: Urinary beta-core hCG has been investigated in a number of studies and shown to be raised in pregnancies with Down's syndrome. This area is currently the subject of active research and the use of urine in future screening programmes may be a practical possibility. Other urinary markers, such as total oestriol and free beta-hCG may also be of value. Fetal cells can be identified in the maternal circulation and techniques such as fluorescent in situ hybridisation can be used to identify aneuploidies, including Down's syndrome and trisomy 18. This approach may, in the future, be of value in screening or diagnosis. Currently, the techniques available do not have the performance, simplicity, or economy needed to replace existing methods. DEMONSTRATION PROJECTS: Demonstration projects are valuable in determining the feasibility of screening and in refining the practical application of screening. They are of less value in determining the performance of different screening methods. Several demonstration projects have been conducted using the triple and double tests. In general, the uptake of screening was about 80%. The screen positive rates were about 5-6%. About 80% of women with positive screening results had an invasive diagnostic test, and of those found to have a pregnancy with Down's syndrome, about 90% chose to have a termination of pregnancy. ULTRASOUND MARKERS AT 15-22 WEEKS OF PREGNANCY: There are a number of ultrasound markers of Down's syndrome at 15-22 weeks, including nuchal fold thickness, cardiac abnormalities, duodenal atresia, femur length, humerus length, pyelectasis, and hyperechogenic bowel. (ABSTRA  相似文献   

6.
BACKGROUND: Microbial invasion of the amniotic cavity plays a major role in the pathogenesis of preterm labor and delivery in singleton pregnancy. Nevertheless, this association is not well established among patients with multiple gestations. The purpose of our study was to explore the role of intraamniotic infection in the setting of twin pregnancies. METHODS: Consecutive women with twin gestations, intact membranes and preterm labor who underwent transabdominal amniocentesis under sonographic guidance. Amniotic fluid (AF) was retrieved from both sacs and cultured for aerobic and anaerobic microorganisms as well as for Mycoplasma species. Intraamniotic infection was defined as a positive AF culture for microorganisms. Mann Whitney U test or Student t-test or Fisher's exact test were utilized for analysis. RESULTS: Amniotic fluid was obtained from 74 patients. Sixty-eight women delivered prematurely (91.9%). Amniotic fluid culture results were positive for microorganisms in nine cases and all women with intraamniotic infection delivered prematurely as well as 59 (90.7%) patients with negative culture. Among the nine patients with intraamniotic infection, microorganisms were isolated from the presenting sac in five cases (55.6%), from both sacs in three patients (33.3%) and from the upper sac in the remaining case (11.1%). Patients with a positive AF culture had a more advanced cervical dilatation, a shorter interval amniocentesis-to-delivery and a higher incidence of clinical chorioamnionitis than those with a negative AF culture. CONCLUSIONS: The prevalence of intraamniotic infection and clinical and histological chorioamnionitis in twin pregnancies and preterm labor is similar to singleton pregnancies and preterm labor. Therefore, women with multiple gestations and preterm labor should be managed as singleton pregnancies.  相似文献   

7.
A retrospective evaluation of alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated oestriol (uE3) levels in maternal blood in the second trimester was conducted for cases of aneuploid pregnancies identified from a series of women who underwent amniocentesis. Blood samples were collected from 1078 women just before genetic amniocentesis was performed, mainly for individuals of advanced maternal age (greater than 35 years). Twenty-five maternal serum samples from pregnant women with an aneuploid fetus, including 14 with Down's syndrome, were available for analysis of all three parameters. An algorithm to detect Down's syndrome was used for this analysis with a risk of > or = 1:299 classified as screen-positive, this being found for 20.4 per cent of the cases (220/1078). The actual Down's syndrome detection rate was 85.7 per cent (12/14), whereas the detection rate for all aneuploidies was 72.0 per cent (18/25). Those that were not detected were two cases of trisomy 21, one trisomy 18, two trisomy 13, three sex chromosome abnormalities, and one case of an additional marker chromosome. The data indicate that this tri-analyte test should be provided after thorough genetic counselling and informed decision-making regarding maternal serum screening for women who wish for a prenatal diagnosis.  相似文献   

8.
OBJECTIVES: To present the complications of twin pregnancies with delayed delivery of the second twin, 32 days after expulsion of the first twin. CASE: A 29-year-old woman with a twin pregnancy at gestational age 13 weeks and 5 days presenting with a rupture of the membranes of the first twin. At 21 completed weeks the umbilical cord prolapsed and at 23 weeks the first twin was stillborn with the placenta in the uterus. After maternal septicemia the second twin was delivered by caesarian section, at 28 complete weeks, liveborn. The mother and child were discharged from hospital 10 weeks later, corresponding to 38 completed weeks of pregnancy. CONCLUSIONS: A very early premature rupture of membrane (PROM) occurs more often in twin pregnancies. The delivery of one twin most often results in expulsion of the second twin. With PROM there is a great risk of chorioamnionitis, as in our case, which resulted in an acute cesarean section. In this case, conservative management achieved a viable fetus in spite of very early and serious complications.  相似文献   

9.
OBJECTIVE: Our purpose was to ascertain the screening efficiency of a new midtrimester Down syndrome detection protocol that combines maternal urine testing and ultrasonographic examination. STUDY DESIGN: In a prospective study, beta-core fragment, the stable end product of human chorionic gonadotropin metabolism, was measured in maternal urine. The results were standardized for urine creatinine levels. The study was performed in women undergoing midtrimester genetic amniocentesis (15 to 24 weeks' gestation). Urine beta-core fragment values were expressed as multiples of the normal median for gestational age. The screening performance of a combination of ultrasonographic parameters and urine beta-core values for Down syndrome detection was determined. RESULTS: A total of 511 singleton pregnancies in women undergoing amniocentesis were studied, 18 of the women (3.5%) had a Down syndrome fetus. A urine beta-core fragment level > or = 97th percentile had a sensitivity of 61.1% and a false-positive rate of 3.2%. An abnormal prenatal screen was defined as a urine beta-core level > or = 97th percentile, increased nuchal thickness (> or = 5 mm), or the presence of gross structural defects. Corresponding values for the screening efficiency of an abnormal prenatal screen were sensitivity of 77.8% and a false-positive rate of 4.1%. With an abnormal prenatal screen the odds ratio is 82.8 (95% confidence interval 22.6 to 364.9) for having a Down syndrome fetus. CONCLUSION: The presence of an abnormal maternal urine beta-core level, a gross ultrasonographic anomaly, or increased nuchal thickness had a high detection rate and a low false-positive rate for Down syndrome. This novel screening algorithm is useful for further delineating the risk status in patients at high risk who are reluctant to undergo or decline genetic amniocentesis.  相似文献   

10.
OBJECTIVE: To assess past care practices of neurologists and obstetricians to identify areas in which practice patterns differ from currently accepted optimal care. METHODS: Retrospective chart review of 155 women identified as having a diagnosis of epilepsy (or seizure disorder) who had been pregnant any time between January 1988 and December 1995 and were admitted to Stanford University Hospital for delivery. A total of 161 pregnancies (132 women) were selected for study. RESULTS: An obstetrician was seen at some point during the pregnancy in 99% of the pregnancies, whereas a neurologist was seen at least once in only 64% of the pregnancies. In the 3 months before conception, an obstetrician was seen in 5% of the pregnancies and a neurologist was seen in 15%. Seventy-five percent of the patients taking antiepileptic medication and 65% of the untreated patients had documentation of folate supplementation at any time during pregnancy. Vitamin K supplementation in the final month of pregnancy was documented for only 41% of those receiving antiepileptic drugs. In over one-third of the pregnancies the mother did not have a maternal serum alpha-fetoprotein measure documented and a similar percentage did not receive genetic counseling. Monitoring of the maternal serum concentration of the non-protein-bound fraction of the prescribed antiepileptic drugs was not documented. CONCLUSIONS: We identified specific omissions of appropriate vitamin supplementation, genetic counseling, and drug level monitoring. Educational efforts should be targeted to improve the management of pregnancy in women with epilepsy.  相似文献   

11.
BACKGROUND: Screening of maternal serum to identify fetuses with Down's syndrome is now routinely offered during the second trimester of pregnancy. Prenatal screening by means of serum assays or ultrasonographic measurements, either alone or in combination, may also be possible in the first trimester. METHODS: We measured serum alpha-fetoprotein, unconjugated estriol, human chorionic gonadotropin (hCG), the free beta subunit of hCG, and pregnancy-associated protein A in 4412 women (82 percent of whom were 35 years of age or older) who came to 16 prenatal diagnostic centers for chorionic-villus sampling or early amniocentesis at 9 to 15 weeks of gestation. Ultrasound measurements of fetal nuchal translucency were also reported. Fetal chromosomal analysis was performed in all pregnancies. Altogether, there were 61 fetuses with Down's syndrome. RESULTS: A total of 48 pregnancies affected by Down's syndrome and 3169 unaffected pregnancies were identified before 14 weeks of gestation; the rates of detection of Down's syndrome for the five serum markers were as follows: 17 percent for alpha-fetoprotein, 4 percent for unconjugated estriol, 29 percent for hCG, 25 percent for the free beta subunit of hCG, and 42 percent for pregnancy-associated protein A, at false positive rates of 5 percent. The results of the measurements of serum hCG and its free beta subunit were highly correlated. When used in combination with the serum concentration of pregnancy-associated protein A and maternal age, the detection rate was 63 percent for hCG (95 percent confidence interval, 47 to 76 percent) and 60 percent for its free beta subunit (95 percent confidence interval, 45 to 74 percent). Measurements of nuchal translucency varied considerably between centers and could not be reliably incorporated into our calculations. CONCLUSIONS: Screening for Down's syndrome in the first trimester is feasible, with use of measurements of pregnancy-associated protein A and either hCG or its free beta subunit in maternal serum.  相似文献   

12.
OBJECTIVE: To evaluate the association between maternal weight gain patterns, based on pregravid body mass index (BMI) and birth weight outcome in twins, and to make specific recommendations for maternal weight gain during twin gestation. METHODS: One hundred eighty-nine twin pregnancies were reviewed retrospectively. Weekly rates of maternal weight gain before 20 weeks, from 20 weeks to delivery, and for total gestation were calculated. Thresholds of weekly maternal weight gain were determined for underweight and normal-weight women. RESULTS: In underweight women, a higher weekly rate of gain before 20 weeks was associated with the birth of both twins weighing at least 2500 g (1.13 versus 0.70 lb/week, P = .017), when compared with mothers of at least one twin weighing less than 2500 g. A higher rate of weight gain from 20 weeks to delivery was associated with the delivery of twins weighing at least 2500 g in both underweight (1.92 versus 1.29 lb/week, P = .031) and normal weight (1.63 versus 1.29 lb/week, P = .046) women. No significant differences in weight gain patterns were found between overweight women delivering twins weighing less than 2500 g or at least 2500 g. A weekly rate of gain from 20 weeks' gestation to delivery of at least 1.75 lb/week in underweight women and at least 1.50 lb/week in normal-weight women was associated with the birth of both twins weighing at least 2500 g. After controlling for other potential determinants of birth weight, the threshold of 1.75 lb/week in underweight women showed a trend toward significance as an independent predictor of both twins weighing at least 2500 g (P = .06). CONCLUSION: Certain maternal weight gain patterns during twin pregnancy are associated with the birth of each twin weighing at least 2500 g. As with singletons, recommendations for maternal weight gain during twin pregnancy can be based on pregravid BMI.  相似文献   

13.
PURPOSE: A matched case-control study of all pregnancies obtained after either IVF or ICSI was conducted to investigate the perinatal outcome. METHODS: Three hundred eleven singleton and 115 twin pregnancies obtained after assisted reproduction were studied. Controls were selected from a regional register and were matched for maternal age, parity, singleton or twin pregnancy, and date of delivery. RESULTS: No significant difference was observed for gestational age at delivery, birth weight, incidence of congenital anomalies, and incidence of perinatal mortality between ART (singleton and twin) pregnancies and spontaneous controls. ART twin pregnancies showed a higher incidence of preterm deliveries than control pregnancies (52 vs 42%; P < 0.05) and needed more neonatal intensive care (47 vs 26%; P < 0.05). CONCLUSIONS: From this case-control study it is concluded that the perinatal outcome of ART singleton pregnancies is not different from that in matched controls. ART twin pregnancies showed a higher incidence of preterm deliveries than control pregnancies and needed more neonatal intensive care.  相似文献   

14.
OBJECTIVE: To assess the utility of biochemical antenatal screening for Down's syndrome in a socioeconomically deprived area with a high proportion of Asian women from the Indian Subcontinent. DESIGN: Audit of Down's syndrome biochemical screening service over a four-year period. SETTING: Teaching hospital and community antenatal clinic in inner city Birmingham. POPULATION: Women booked between October 1992 and December 1996. METHODS: Blood for screening was collected between 14 and 21 weeks gestation, alpha-fetoprotein and intact human chorionic gonadotrophin were measured in serum and the risk of Down's syndrome was calculated. MAIN OUTCOME MEASURES: Uptakes of screening and amniocentesis, screen positive rate, odds of being affected given a positive result, miscarriages associated with amniocentesis offered following a high risk result, detection rate, number of Down's cases prevented and a cost analysis. Outcome measures were compared between Asians and Caucasians. RESULTS: Overall 11,974 women (71%) accepted serum screening. The screen positive rate was 8.3% in Asians and 5.0% in Caucasians. The uptake of amniocentesis in women following a high risk result was 54% overall (35% Asian, 67% Caucasian). Nineteen cases of Down's syndrome were identified, of which 13 occurred in women who opted for biochemical screening. The detection rate of the biochemical screening programme was 85% (11/13). Of these 11 cases, six (none of whom were Asian) elected to have an amniocentesis, of whom four thereafter had a termination. CONCLUSION: In this study the public health benefits of screening for Down's syndrome in a socioeconomically deprived area with a high Asian population, were small.  相似文献   

15.
OBJECTIVE: To derive a method for revising the risk of Down's syndrome in maternal serum marker screening when there is vaginal bleeding. The effect on screening performance of routinely allowing for the presence or absence of bleeding in all women is also assessed. DESIGN: Overview of published studies on the rate of reported vaginal bleeding in pregnancies with Down's syndrome, on the rate according to maternal age and on the association of bleeding with alpha-fetoprotein (AFP) level. The publications are supplemented with data on unconjugated oestriol (uE3), human chorionic gonadotrophin (hCG) and AFP levels in a consecutive series of screened women. SETTING: Routine Down's syndrome screening tests carried out on women having antenatal care at the St James's University Hospital, Leeds. SUBJECTS: Eight hundred and nine screened women. RESULTS: In five studies the rate of vaginal bleeding in Down's syndrome pregnancies was 1.7 times that in unaffected pregnancies on average. In three studies, the vaginal bleeding rate increased proportionally by 2.2% on average for each year of maternal age. Three studies and our own data were consistent with a 10% increase in the mean AFP level associated with vaginal bleeding, but it did not appear to materially alter uE3 and hCG levels or the standard deviations and correlation coefficients for any of the three analytes. An individual woman's risk was calculated by multiplying her age-specific odds of Down's syndrome by two likelihood ratios, one relating to the vaginal bleeding itself and one from the marker levels. Routine allowance for the presence or absence of vaginal bleeding was estimated to increase the detection rate by less than 1%. CONCLUSION: Our method is of clinical value in revising the risk when there is concern that vaginal bleeding might be responsible for a negative maternal serum Down's syndrome screening result. A policy of routinely incorporating information on vaginal bleeding in risk estimation for all women would have too small an effect on overall screening performance to recommend it.  相似文献   

16.
BACKGROUND: Early amniocentesis has been claimed to confer a higher risk of fetal loss than standard amniocentesis after the 15th gestational week. Our experience of early amniocentesis in single and twin gestations from 1990 - 1995 is presented with 99.3% follow-up. METHODS: Amniocentesis was performed between 11 gestational weeks + 5 days and 14 gestational weeks + 6 days. RESULTS: In 1646 pregnancies 1678 amniocenteses were performed. Thirty-two reamniocenteses were done, 17 due to amniocyte culture failure and 15 due to failure to obtain sufficient amount of amniotic fluid on the first occasion. After puncture 1.49% (25/1678) suffered a spontaneous abortion. Twenty twin pregnancies were included. One spontaneous abortion was noted in this group, as well as three cases where one fetus was normal and the other had a severe defect. Selective abortions were performed without complications. CONCLUSIONS: The difference of postprocedure fetal loss in our population between early and standard amniocentesis is 0.8%. A comparison of postprocedure losses is not appropriate when amniocenteses are performed at a different gestational age, as spontaneous loss decreases with increased gestational age. Our results compare well with the only randomized study between early and standard amniocentesis where the fetal loss after early amniocentesis is similar to that in standard amniocentesis.  相似文献   

17.
OBJECTIVE: The purpose of this study was to investigate the efficiency of second-trimester maternal serum screening for Down's syndrome and open neural tube defects using alpha-fetoprotein and free beta-human chorionic gonadotropin as serum markers. METHODS: 3, 188 women underwent testing between 14th and 22nd week of pregnancy. Of all tested patients, 25.4% were >/=35 years old. A cut-off risk of >/=1:250 for Down's syndrome and MS-AFP >/=2.0 MoM for open neural tube defect were considered screen-positive. RESULTS: The detection rate for Down's syndrome was 77.8% (7/9) with 8.2% screen-positive rate (7.9% false-positive rate). When evaluated separately, in patients younger than 35 and in those >/=35 years old, the screen-positive rates were 3.1 and 23.3%, respectively. A total of 52 (1.6%) were found screen-positive for open neural tube defect; 2 cases of encephalocela and 1 case of gastroschisis were confirmed prenatally. CONCLUSION: The respectable number of cases with trisomy 21 identified in this study confirms that routine mid-trimester screening for Down's syndrome including MS-AFP, free beta-hCG and maternal age is useful in identifying pregnancies at increased risk.  相似文献   

18.
Neonatal lupus erythematosus (NLE) is characterized by persistent congenital complete heart block, often without any other structural heart defects. Lupus-like dermatitis is seen transiently, more rarely hepatitis and thrombocytopenia occurs. Recent investigations have shown a close relation between NLE and maternal anti-Ro/La antibodies. These antibodies seem responsible for the destruction of the bundle of His and the AV node in the foetus. Total AV block is seen in 1:15.-22,000 of liveborn children, 70-90% of them are caused by NLE. It is difficult to identify the pregnancies at risk since at delivery most of the mothers (up to 66%) are without symptoms. If the mother has anti-Ro/La antibodies the risk for having a child with NLE is probably less than 5%. However, new investigations have shown that mothers who in addition have anti-DNA antibodies have significantly lower risk of bearing a child with NLE. In most cases foetal complete AV block is found accidentally during pregnancy. Slow foetal heart rate with the demonstration of AV dissociation should not, unless the foetus shows sign of incompensation, lead to acute delivery, but pregnancy should be monitored carefully by serial echocardiography. More than half of the children with congenital heart block need pacemaker therapy shortly after birth. The other children should be followed closely for signs of incompensation and may need pacemaker therapy later on.  相似文献   

19.
The independent associations between parity and maternal body mass index (BMI), and between parity and maternal weight gain, were investigated using a combination of cross-sectional and longitudinal analyses based on a retrospective, repeat-pregnancy study that examined the change in maternal body weight from the beginning of one pregnancy to the beginning of the next. A group of 523 multiparous women who had been weighed regularly during pregnancy, and none of whom had fallen pregnant less than 12 months after the birth of their previous child, were examined. Sociodemographic, behavioural, medical, obstetric and perinatal data, together with antenatal measurements of maternal body weight and height, were abstracted from each mother's obstetric notes. Parity was found to be independently associated with maternal BMI (p < 0.001), gestational weight gain (p < 0.001) and interpregnancy weight gain (p = 0.032). Women of different parities were found to be at differential risk of long-term weight gain for two reasons. First, primiparous women are at risk of long-term weight gain because they gain the most weight during pregnancy, and high gestational weight gain is in itself a risk factor for long-term weight gain. Second, women of higher parity (4+) are at risk of long-term weight gain because they gain more weight in association with pregnancy, irrespective of the amount of weight they gain during their pregnancies. For women of parity 3 or less, the association between maternal body weight and parity appears to be the result of cumulative weight gained during successive pregnancies. For women of greater parity, the association between maternal body weight and parity is partly the result of cumulative excess gestational weight gained during successive pregnancies, and partly the result of gaining more weight from the beginning of one pregnancy to the next at later pregnancies.  相似文献   

20.
AIM: To establish a baseline cross-sectional prevalence of maternal smoking, measured by antenatal serum cotinine testing, in a population of pregnant women. METHODS: Residual sera from first and second routine antenatal blood samples were collected anonymously over a six-month period for pregnancies within the Canterbury region. Cotinine levels were measured by an ELISA test with a result of > 14 ng/mL indicative of active smoking. Only pregnancies ending in a confirmed live birth were considered in smoking prevalence calculations. There was a total of 1948 eligible residual blood samples. RESULTS: Of the 414 residual blood samples available for the first two months of pregnancy, 146 (35.3%) were found to be positive for cotinine. Smoking prevalence decreased over pregnancy so that by the third trimester 225 (26.8%) of 838 samples were cotinine positive. Infants born from smoking mothers had significantly lower birth weights. CONCLUSIONS: In 1994, a third of women tested in early pregnancy and a quarter of women tested in late pregnancy were identified as being smokers. Repeated objective cross-sectional surveys will allow accurate assessment of the efficacy of smokefree interventions both before and during pregnancy.  相似文献   

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