Epidemiological studies of obstetric ultrasound examinations in Denmark 1989-1990 versus 1994-1995

BACKGROUND: The purpose of the study was to describe number, type, time and place for all obstetric ultrasound examinations that pregnant women in Denmark had performed during their pregnancies. Further, to compare these results with results from a similar national survey performed five years previously. METHODS: During a two-week period in February 1990 and a two-week period in May 1995, all delivery departments in Denmark (1990: 57/1995: 49) participated in two identical designed studies with the aim as described above. For all women who delivered in these periods variables were recorded from the women's case records and after interview. After the exclusion of 108/145 women without complete registrations, the material consisted of 2268/2315 women; approximately 3.7%/3.4% of all deliveries in Denmark 1990/1995. The chi2 and t-test were used for statistical analyses with a statistical significance level of 5%. RESULTS: Of all obstetric ultrasound examinations 99%/96% took place in hospitals. Twenty/seven percent of the women had no examination during their pregnancies. The mean number of obstetric ultrasound examinations was 1.5/1.9 for all women and 1.9/2.1 for women who had at least one examination. In total 40%/54% of the women were offered a screening examination. Women with an offer of screening had a mean number of examinations: 1.8/2.0 and women without an offer: 1.3/1.9 (1990: p<0.05; 1995: non-significant). CONCLUSION: The studies have shown an increasing number of women with an offer of ultrasound screening and in general an increased use of ultrasound examinations in obstetrics during the five year period 1990-1995 in Denmark.     

Early echography subprogramm. Southern Metropolitan Health Service evaluation 1989-1990]

The results of an early level I ultrasound program performed in the Southern Health Area of Santiago during the years 1989 and 1991 are reported. It was noticed that suspect gestational age constituted the highest number of ambulatory attentions (23.9%) in the High Risk Obstetric Department of Barros Luco Trudeau Hospital in 1987. With this program, in 1990, 82% of pregnant women were examined before 20 weeks' gestation, with a total of 10447 ultrasound examinations. Suspect gestational age descended to 8.6% in 1990 (compared with 23.9% in 1987). Amniocentesis and amnioscopies also diminished abruptly. The value of early routine level I ultrasound program in obstetric population improves maternal, fetal and newborn health indexes. These conditions are discussed.     

Management of pregnancies with suspected intrauterine growth retardation in Sweden. Results of a questionnaire

BACKGROUND: Diagnosis and management of intrauterine growth retardation during pregnancy remain a major challenge in obstetric care. The objective of this survey was to evaluate the routine clinical management of pregnancies with suspected intrauterine growth retardation at obstetric departments in Sweden. METHODS: In 1997, a questionnaire was sent to all 59 obstetric departments in Sweden. Forty-two departments, caring for 83% of all deliveries in Sweden, replied. Four major topics were addressed: definition and diagnosis of intrauterine growth retardation; magnitude of the problem; clinical management; use of Doppler ultrasound in clinical decision-making. RESULTS: Intrauterine growth retardation is diagnosed by a combination of serial fundal height measurements and ultrasonic fetal biometry at 40 departments, two departments perform routine fetal biometry at 32 weeks. The diagnosis is most often made at 32-36 gestational weeks. Five departments use 1.5 s.d. below the mean as cut-off point for diagnosis of small for gestational age fetuses; 35 departments use mean - 2 s.d. and two departments mean - 2.5 s.d. Intrauterine growth retardation is suspected in 1.6-6.3% pregnancies. About 19% of patients with suspected intrauterine growth retardation are hospitalized. On average, 63% of all small-for-gestational age babies are diagnosed prenatally. Thirty-nine out of 42 obstetric departments use formalized management protocols. All departments use cardiotocography, repeat ultrasound scans and Doppler ultrasound for antenatal surveillance. CONCLUSIONS: In Swedish obstetric units, the diagnostic procedures and methods of fetal surveillance in pregnancies suspected of intrauterine growth retardation are more or less uniform. Doppler examination of umbilical artery is used at all responding departments and is considered a valuable asset in clinical decision-making.     

Routine ultrasound scanning for the detection and management of twin pregnancies

One thousand five hundred fifty-one private patients underwent routine ultrasound scanning in part to detect twins. Five thousand nine hundred fifty private patients acted as controls and underwent ultrasound scanning only when indicated by conventional obstetric standards. When diagnosed, twin pregnancy was treated with increased bed rest, nutritional counseling and careful monitoring, with delivery in a tertiary-level center. No significant differences between the two groups could be demonstrated in maternal age, parity or incidence of twin pregnancy. A significant difference could be shown, however, in the early detection of twin pregnancy. By the end of the 24th week, 94% of the twins in the routinely scanned group had been diagnosed as compared to only 68% in the controls (p = 0.03). A significant improvement in perinatal outcome was also demonstrated in the routinely scanned patients as compared to the controls. The incidence of any unfavorable outcome in any infant was reduced from 60% in the controls to 25% in the routinely scanned patients (p = 0.0007). This reduction was due to a reduced incidence of low birth weight, smallness for gestational age, prematurity, depressed Apgar scores and stillbirths. When all twins diagnosed prior to the 25th week of pregnancy were compared with those diagnosed after that week, similar findings were demonstrated.     

Controlled trial of ultrasound screening for light for gestational age (LGA) infants in late pregnancy

The study included 3311 pregnant women: 1570 in the screened group and 1741 in the unscreened group. In the screened group, ultrasound was offered routinely in the 32nd and 37th week of pregnancy, at which time the fetal biparietal diameter (BPD) and the abdominal mean diameter (AD) were measured. If, after the first ultrasound examination, the estimated weight was less than 85% of the expected mean birthweight, a finding of light for gestational age (LGA) was suspected and the ultrasound examination was repeated in the 34th week. In the screened group 6.5% of the women were at risk at the final ultrasound examination (the sensitivity was 38%) and the predictive values of abnormal and normal weight deviation were 60% and 93%, with a specificity of 97% and a relative risk of 9. Ultrasound was offered to the unscreened group only in cases of clinical concern (23% of the women). In the unscreened group 34% of the 158 LGA infants had ultrasound performed before delivery because of clinical concern. By including pregnancies induced before ultrasound could be performed, 45% of the LGA infants in the unscreened group were suspected before delivery. No significant difference between the rate of induction, instrumental deliveries and caesarean sections was found between the two groups. No benefit in terms of decreased incidence of infants with low Apgar score and acidosis was achieved.     

Diagnostic methods for fetal malformations in the first half of pregnancy

INTRODUCTION: Fetal abnormalities are the most common cause of perinatal and postnatal death and infant handicap. For this reason prenatal screening (for fetal malformation) has become a routine part of obstetric care in many countries. Most often used are biochemical tests and continuously developing ultrasound diagnostics which makes possible precise analysis of the fetal morphology. There is interesting to establish a noninvasive test for the early detection of fetal malformation in pregnancy which is based on ultrasound examination (NT measurement from the 10th to the 19th weeks, presence of nasal bone in the first trimester ultrasound), correlated with serum concentration of AFP, beta-HCG and oestriol in the second trimester of pregnancy (triple test). The main aim of the study was to establish a diagnostic schema for detection of fetal malformations based on NT measurement in the first and second trimester coupled with triple test performed in the second trimester. MATERIALS AND METHODS: A group of 775 pregnant women from the 10-th week of pregnancy until childbirth has been put under examination. Between the 10th and the 14th and than between 15th and 19th week of pregnancy ultrasound examination with fetal biometry and NT measurement was done. NT measurements have been performed in accordance with the standards worked out by professor K. Nicolaides. At the first ultrasound examination the presence of the nasal bone was observed. The next step was performing the triple test between the 15th and 19th week of pregnancy. On the same day as second ultrasound examination blood was taken to determine the results of the triple test (ELISA method). The obtained results have undergone statistical analysis. RESULTS: The age of women qualified for the examination oscillated between 15 and 45 (over 35 -9.4%). There were 8 fetal malformations recognized all connected with the chromosomal anomalies, namely, 4 Downs syndrome, 2 fetuses with trisomy of the 18th pair of chromosomes and 2 with triploidy. At all physiologic pregnancies nasal bone was seen during first ultrasound examination. The obtained results of nuchal fold measurements and concentrations for the parameters of the triple test have been the basis to calculate medians in the particular weeks of pregnancy. In all the cases of genetic malformations the widening of the nuchal fold above 99 percentile (MoM NT) has been observed. Fetal nasal bone were absent in 62.5% first trimester ultrasound examinations. The risk of the occurrence of a genetic malformation resulting from the mother's age combined with the risk connected with the NT measurements and the results of the triple test for the cut-off point 1:250 (which seems to be the best for this population) gave 100% sensitivity, 0.6% % of false positive results and the positive predictive value of 80%. The above mentioned results are better than the ones which were obtained within the triple test only, where for the previously fixed cut-off point 1:250 sensitivity reached 63%, positive predictive value 25% and 4.4% false positive rate. Performing the so-called integrated test in which the risk of the occurrence of any malformation is estimated on the basis of the NT measurement in the first and the second term of pregnancy seems to be far more useful. CONCLUSIONS: Diagnostic schema for detection of fetal malformations in the first half of pregnancy which is based on ultrasound examination (NT measurement from the 10th to the 19th weeks), correlated with serum concentration of AFP, beta-HCG and oestriol in the second trimester of pregnancy (triple test) is very sensitive and safe method of the prenatal diagnosis leading to significant decrease of the invasive procedures (amniocentesis).     

Ultrasonic estimation of weight in the very low-birth weight fetus: a resident versus staff physician comparison

The estimation of weight in the very low-birth weight fetus (less than 1500 gm) is becoming more important in obstetric management as neonatal nurseries are reporting better outcome in this weight category. It has become clear that assessment of weight can best be accomplished through the use of ultrasound. In many institutions, however, ultrasonography is under the control of other departments and is not readily available. This arrangement prevents rapid access and compromises the benefit of the technique. To evaluate the accuracy of scans performed in very low-birth weight infants by personnel with limited training in ultrasonography, we undertook a systematic study of weight estimates in this select group of patients. To date, 31 ultrasound examinations have been performed by staff physicians and 50 by resident physicians. Comparisons made between ultrasound examinations by staff and resident physicians showed that the absolute error between the ultrasound-predicted weight and the actual weight, though less in the case of staff physician examinations, was not statistically significant.     

A validation of the diagnosis of obstetric sphincter tears in two Norwegian databases, the Medical Birth Registry and the Patient Administration System

BACKGROUND: The purpose of the present study was to validate the registration of obstetric sphincter tears in 2 registers, the Medical Birth Registry of Norway [MBRN] and Patient Administration System [PAS]. METHODS: A retrospective cohort study of all obstetric sphincter tears that occurred in our department in 1990-1992 and 2000-2002 was performed. The case records of all patients registered either in MBRN, PAS or the birth logs were compared with the information in the medical records, which constituted the 'golden standard'. RESULTS: The incidence of obstetric sphincter tears in 1990-1992 was 5.8% (774/13381), 5.6% (745/13381) had a perineal tear of third degree and 0.2% (29/13381) of fourth degree. In 2000-2002, the total incidence was 6.6% (813/12380), 5.9% (731/12380) was a third degree perineal tear and 0.7% (82/12380) fourth degree, respectively. The sensitivity and specificity of the MBRN database to detect obstetric sphincter tears was 85.3 and 99.5% in 1990-1992, and 91.8 and 99.7% in 2000-2002, respectively. The positive and negative predictive values of a MBRN-registered diagnosis of obstetric sphincter tears in 1990-1992 were 91.4 and 99.1%, while the corresponding percentages in 2000-2002 were 95.4 and 99.4%, respectively. The sensitivity and specificity of the PAS database was correspondingly 52.1 and 99.0% in 1990-1992, and 84.6 and 98.5% in 2000-2002. The positive and negative predictive values of a PAS-diagnosis of obstetric sphincter tears were 75.8 and 97.1% in 1990-1992. In 2000-2002, they were 92.7 and 98.9%, respectively. CONCLUSION: The validity of a diagnosis of obstetric sphincter tears, based on the MBRN, is sufficiently high to justify future large-scale epidemiologic studies based on this database, while the validity of a PAS diagnosis is lower, but improves.     

Prenatal ultrasonographic detection of gastrointestinal obstruction: results from 18 European congenital anomaly registries

OBJECTIVES: We evaluated the prenatal detection of gastrointestinal obstruction (GIO, including atresia, stenosis, absence or fistula) by routine ultrasonographic examination in an unselected population all over Europe. METHODS: Data from 18 congenital malformation registries in 11 European countries were analysed. These multisource registries used the same methodology. All fetuses/neonates with GIO confirmed within 1 week after birth who had prenatal sonography and were born during the study period (1 July 1996 to 31 December 1998) were included. RESULTS: There were 670 793 births in the area covered and 349 fetuses/neonates had GIO. The prenatal detection rate of GIO was 34%; of these 40% were detected < or = 24 weeks of gestation (WG). A total of 31% (60/192) of the isolated GIO were detected prenatally, as were 38% (59/157) of the associated GIO (p=0.26). The detection rate was 25% for esophageal obstruction (31/122), 52% for duodenal obstruction (33/64), 40% for small intestine obstruction (27/68) and 29% for large intestine obstruction (28/95) (p=0.002). The detection rate was higher in countries with a policy of routine obstetric ultrasound. Fifteen percent of pregnancies were terminated (51/349). Eleven of these had chromosomal anomalies, 31 multiple malformations, eight non-chromosomal recognized syndromes, and one isolated GIO. The participating registries reflect the various national policies for termination of pregnancy (TOP), but TOPs after 24 WG (11/51) do not appear to be performed more frequently in countries with a liberal TOP policy. CONCLUSION: This European study shows that the detection rate of GIO depends on the screening policy and on the sonographic detectability of GIO subgroups.     

Prenatal diagnosis of haemoglobin Bart's disease by cordocentesis at 12-14 weeks--experience with the first 59 cases

We have shown that fetuses affected by haemoglobin (Hb) Bart's disease can be reliably identified by their sonographic manifestation of cardiac enlargement at 12-14 weeks. Between 1995 and 1999, 282 couples were seen before 15 weeks. They were offered the options of chorionic villus sampling, or amniocentesis and DNA study, or ultrasound examination at 12-14 weeks, followed by cordocentesis and Hb study only when the ultrasound findings were abnormal. Two hundred and thirty-four at-risk pregnancies had ultrasound assessment at 12-14 weeks, 62 fetuses showed enlarged cardiothoracic ratio [mean (SD) 0.54 (0.02)] and four of them also had hydropic changes. Fifty-nine women agreed to undergo cordocentesis at 12-14 weeks and the procedure was successful in 57 cases (97%). Cordocentesis were performed by a freehand technique using a 26- or 24-gauge spinal needle with a 20-gauge introducer. Fifteen fetuses (25%) had bleeding from the cord and 12 fetuses (20%) had bradycardia following cordocentesis. The fetal loss rate was 8% (5/59). Hb Bart's disease was confirmed in all the 62 fetuses with cardiac enlargement. Their Hb concentration ranged between 3.1 to 8.4 g/dl. One hundred and seventy-two fetuses had normal ultrasound assessment and 148 of them were confirmed to be unaffected by Hb Bart's disease. Twenty-three pregnancies were ongoing and one miscarried at 15 weeks. We believe that sonographic assessment followed by selective cordocentesis at 12-14 weeks is a feasible prenatal diagnostic option for Hb Bart's disease.     

Significance of the ultrasound location of placental site in early pregnancy

The placenta was located by routine ultrasound scanning before 24 weeks gestation in 615 consecutive obstetric patients. A 'low lying' placenta was present in 175 (28 per cent) of the total group; the incidence decreasing from 32 per cent at 16 weeks gestation to 18 per cent at 24 weeks. Of 94 women with an initial 'low lying' placenta who were selected for rescanning, only five had a placenta praevia persisting beyond the 34th week. Patients with an early 'low lying' placenta had a significantly higher incidence of small-for-dates babies than those in whom the placenta remained clear of the internal cervical os on ultrasound scanning.     

Induced abortion in the first trimester of pregnancy and risk of miscarriage

Objective To analyse the relation between induced abortion and risk of subsequent miscarriage.
Design Case-control study conducted between February 1990 and May 1995.
Participants Case group included 782 women (median age 32 years, range 1446) admitted for spontaneous abortion (within the 12th week of gestation) to a network of obstetric departments in the greater Milan area. The control group was recruited among women who gave birth at term (> 37 weeks of gestation) to healthy infants on randomly selected days at the hospitals where cases had been identified. A total of 1543 controls (median age 30 years, range 14–45) were interviewed.
Results A total of 102 cases (13%) and 181 controls (12%) reported one or more induced abortions. No clear relation emerged between miscarriage and induced abortions. In comparison with women reporting no induced abortion the odds ratio (OR) for miscarriage were 1.1 (95% CI 0.8–1.4) in women reporting one induced abortion and 0.9 (95% CI 0.4–1.8) in women reporting two or more. Likewise, there was no association between time since last and age at first induced abortion and risk of miscarriage.
Conclusions This study did not find any strong association between induced and spontaneous abortion.     

The use of record linkage for auditing the uptake and outcome of prenatal serum screening and prenatal diagnostic tests for Down syndrome

OBJECTIVES: To pilot the use of linked routine records for auditing Down syndrome prenatal serum screening and diagnostic tests. METHODS: The cohort studied were 110 272 patients of 4 London maternity units that offered the Bart's maternal serum tests any time between 1990 and 1999. Audit was based on linked data derived from obstetric records, referral data on maternal serum screening and/or prenatal diagnoses. Cytogenetic reports without matching obstetric data were retained in the cohort as they included fetal deaths or terminations. RESULTS: (1) Significant independent influences on uptake of serum screening (58% overall) were maternal age, ethnicity, year and referring hospital, and those on uptake of prenatal diagnosis (4% overall) were screening result (54% uptake after positive screen), maternal age, year and referring hospital; (2) detection, false-positive rates and odds of being affected after positive results were respectively 49%, 4% and 1 : 59 between 1990 and 1994, and 78%, 7% and 1 : 58 after 1994. Using maternal age alone (cut-off > or =37 at delivery), these would have been respectively 40%, 7% and 1 : 96 between 1990 and 1994, and 40%, 9% and 1 : 107 between 1995 and 1999. CONCLUSIONS: Ongoing audit of DS prenatal programmes could be derived from computerised maternity data sets if they included fetal deaths, and relevant laboratory and ultrasound findings.     

“Fetal Growth Charts”: Comparison of Cross-Sectional Ultrasound Examinations with Birth Weight

We examined the hypothesis that fetal growth curves derived from birth weight data deviate significantly from growth curves generated from cross-sectional ultrasound estimated fetal weight. Fetal growth curves created from birth weight data were compared with growth curves generated from ultrasound examinations collected cross-sectionally (350 observations each). Groups were distributed by gestational age between 26 and 39 weeks gestation (25 observations per week). Ultrasound examinations were performed for size/dates discrepancy. Menstrual age was confirmed by ultrasound in each case. One hundred ultrasound examinations performed for size/dates discrepancy (with dating confirmed) were prospectively evaluated to compare the distribution of fetal weight percentile between the two charts. Regression lines for the growth curves were significantly different (P < 0.001). For each gestational age between 26 and 35 weeks, the ultrasound estimated fetal weights demonstrated a higher mean fetal weight (P < 0.05). Prospectively, the mean percentile of fetal weight for birth weight derived growth charts was 65% compared to 45% for the ultrasound defined (P < 0.001). For preterm infants (<35 weeks) the estimation of percentile rank for growth is different between birth weight and ultrasound derived growth curves. Sonographically derived “fetal growth charts” should provide an improved standard when characterizing ultrasound estimates of fetal weight.     

Ultrasound in obstetric decision making. How accurate are late ultrasound scans in gestational age and fetal weight assessment?

Gestational age determination based on obstetric dating criteria, early pregnancy ultrasound scans, Dubowitz examinations, and ultrasound scans performed shortly before delivery were reviewed for 69 preterm infants requiring neonatal intensive care. The last ultrasound scans underestimated gestational age by a median of 8 days, and by 2 weeks or more in 20 of the 69 cases, as opposed to best dating criteria. Ultrasonic fetal weight estimation was more accurate, but erred by more than 20% in 10% of cases. When obstetric decisions regarding preterm neonates must be made without prior information regarding gestational age, late ultrasound findings must be applied with extreme care.     

A randomised controlled trial of moxibustion for breech presentation

OBJECTIVES: To evaluate the efficacy of moxibustion for the correction of fetal breech presentation in a non-Chinese population. DESIGN: Single-blind randomised controlled trial (RCT). SETTING: Six obstetric departments in Italy. SAMPLE: Healthy non-Chinese nulliparous pregnant women at 32-33 weeks + 3 days of gestational age with the fetus in breech presentation. METHODS: Random assignment to treatment or observation. Treatment consisted of moxibustion (stimulation with heat from a stick of Artemisia vulgaris) at the BL 67 acupuncture point (Zhiyin) for one or two weeks. Two weeks after recruitment, each participant was subjected to an ultrasonic examination of the fetal presentation. MAIN OUTCOME MEASURE: Number of participants with cephalic presentation in the 35th week. RESULTS: The study was interrupted when 123 participants had been recruited (46% of the planned sample). Intermediate data monitoring revealed a high number of treatment interruptions. At this point no difference was found in cephalic presentation in the 35th week (treatment group: 22/65, 34%; control group: 21/58, 36%; RR 0.95; 99% CI 0.59-1.5). CONCLUSIONS: The results underline the methodological problems evaluating of a traditional treatment transferred from a different cultural context. They do not support either the effectiveness or the ineffectiveness of moxibustion in correcting fetal breech presentation.     

Chorionic villus sampling: a 15-year experience

The authors describe experiences gained over the period of 1984-1999 at two medical centers with chorionic villus sampling (CVS). Altogether 1,149 CVSs had been performed between the 10th and 32nd gestational weeks. Prior to 1993 the transcervical approach (TC-CVS), after 1994 the transabdominal method (TA-CVS) was used. Analysis of data collected within the framework of this study was based on the following factors: indications for sampling, complications and incidence of pregnancy loss. 91.6% of the CVSs were carried out for the purposes of cytogenetic examination of the fetus. Over the past few years an increasing number of procedures had been carried out for molecular-genetic tests (7.6% of the total number of cases). Though the primary indication for cytogenetic tests was the advanced age of the mother, a remarkable increase in the number of samplings had taken place for the purpose of examining "suspicious ultrasound findings", minor anomalies detected by ultrasound. In this group the proportion of pathological cases was significantly higher (14%) than in all the other samplings, carried out for other indications. This data in itself underlines the importance of ultrasound screening performed in the 18-20th weeks of gestation. Over the first half of the period being reviewed (1984-1993, TC-CVS), a fetal loss of 4.8% occurring within 3 weeks from the date of sampling, dropped to 1.7% in the period subsequent to year 1994 (TA-CVS). In cases of TA-CSV, both the complications and spontaneous abortions were fewer. In 74.1% of the cases studied, birth had taken place after the 37th week of gestation. Premature births (6.4%) and stillbirth rate (1.1%) did not exceed normal rates observed in the general population. On the basis of our results, it is safe to say that in prenatal diagnosis, TA-CVS is a real alternative method of mid-trimester amniocentesis and it is recommended for use at any stage of the pregnancy.     

Participation in prenatal screening tests and intentions concerning selective termination in Finnish maternity care

AIMS: The study examined how prenatal screening tests are presented to women, factors associated with women's participation in screening, their experience of decision-making and intentions concerning pregnancy termination, and hospital data on rates of selective terminations. METHODS: Questionnaires were given to pregnant women visiting maternity centres in two Finnish towns in which serum screening was offered (n = 1,035) and in one town where midtrimester ultrasound screening was offered (n = 497). Response rates to the questionnaires were 88 and 85%, respectively. Other questionnaires asking about selective terminations following detected fetal disorders were sent in 1993 to all public hospitals with obstetrics or gynaecology departments (response rate 100%). RESULTS: The serum screening test had usually been offered to women as a free choice, but for 22% of them it was presented as a routine procedure. Most women (92%) underwent serum screening and most (86%) found the decision to participate or not easy. In almost every aspect of presentation and participation studied, serum and ultrasound screening differed from each other. 85% of respondents to ultrasound screening answered that it was offered as a routine procedure. Close acquaintance with a person with congenital disability was negatively associated with participation in serum screening and with the intention to terminate pregnancy in case of a detected disability. 27% of women in the serum screening survey and 22% in the ultrasound survey declared that they would have declined pregnancy termination if a fetal disorder had been detected. However, according to the hospitals' data, only 13% of pregnancies with a serious fetal disorder detected were continued. CONCLUSIONS: All prenatal screening tests, including ultrasound examinations, require an adequate process of informed consent. Because the aim of such tests is to detect fetal malformations and syndromes, health care professionals should discuss the implications with women before they decide. Because acquaintance with a disabled person was found to associate with participation in screening and with intentions about selective termination, women's perceptions of lives of the disabled should receive more attention in future studies.     

Correlation between indication for amniocentesis and the time of its performing

OBJECTIVES: Prenatal diagnosis of fetal disorders is a very wide range of noninvasive and invasive methods. We use ultrasound examination and biochemical tests as screening tools in the low risk pregnancies. In a high risk pregnancy we perform invasive procedures to obtain definitive diagnosis. Amniocentesis is carried out in the first or in the early second trimester of pregnancy to determine: fetal karyotype, monogenic disorders, metabolic errors, the level of alpha-fetoprotein and acetylocholinesterase. DESIGN: The aim of our study was to determine the impact of the indication to amniocentesis on the time of performing the procedure. MATERIALS AND METHODS: We have analysed all the 721 amniocenteses carried out in the Department of Obstetrics in Gdansk in 1996-2002. Amniocenteses were performed due to: advanced maternal age in 553 cases, fetal malformation in current pregnancy in 39 cases, inherited disease in previous pregnancies in 80 cases, maternal balanced translocation in 6 cases, psychological reasons in 15 cases, inherited diseases in the family in 8 cases and serious obstetric history in 9 cases, abnormal results of triple test in 11 cases. The T-Student test was used for statistical analysis with the significance level p=0.05. RESULTS: The amniocentesis was performed in the 15th (from the 12th to the 26th) week of gestation. Amniocentesis performed because of: advanced maternal age in the 15th (from the 12th to the 25th); foetal malformation in current pregnancy in the 16th (from the 12th to the 26th); inherited disease in previous pregnancies in the 14th (from the 12th to the 18th); maternal balanced translocation in the 13th (from the 13th to the 14th); psychological reasons in the 15th (from the 13th to the 18th); inherited diseases in the family in the 15th (from the 13th to the 22nd); serious obstetric history in the 16th (from the 15th to the 17th); abnormal results of triple test in the 16th (from the 14th to the 19th). There is a statistical difference between time of performing amniocentesis because of advanced maternal age, fetal malformation in current pregnancy, maternal balanced translocation and other indications. CONCLUSION: In pregnancies with serious obstetric history--balanced translocation, inherited disease in previous pregnancies--women decided to perform amniocentesis earlier than in cases when advanced maternal age was the only indication for this procedure.