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Volume 168 Number I, Part 2

CHERNOBYL NUClEAR ACCIDENT - 6 YEARS LATER. 8M Pelrikpyskv M 0 Ph D Department of ObIGyn, North Shorn University Hospital­Cornell Medical Center, Manhasset, NY. OBJECTIVE: Analyses of the effect 01 Chemobyl nuclear accident (CNA) on letal and maternal health in the affected areas. STUDY DESIGN: Demographic and statistical data were obtained from Russian and Ukrainian ministries 01 Public Health and from a questionnaire study involving 52 physicians in the area. BES1n.IS: Table 1 reflects the incidence of fetal and maternal complications in 1983-84 (prior In the CNA) in 1988-89 and in 91 -92. The CNA occurred on April 26, 1986.

Table l' 1963 1988-89 1991-92

Major congenital anomalies (CHD, abdominal wei defects, NTDI

0.92% 2.1% 1.4%

Minor congenital anomalies 2.6 3.2 2.8

IUGR 0.86% 1.9% N/A Abortions on demand 18% 01 all 46% 01 all N/A

preQnancies pregnancies Preterm deliveIY 2% 3% NlA Spontaneous abortions No reliable data available

CONCLUSIONS. Stallstical data related In CNA IS Incomplete dua In

mass migration 01 the population and lack of unilorm reporting system in Russia and Ukraine. Original reports 01 a drastic increased incidence of congenital mallormations seem unjustified. CNA is associated with twolold increase in major congenital anomalies, fourfold - in preterm birth and almost ball 01 pregnancies aborted on demand.

PREYALEIICE ANO ETIOLOGY OF LOll BIRTlllE16HT IN IRfANTS IIITH MAJOR COII6EIIITAL AIIOIIALIES . S. Baker. R. Goldenberg. J . Hauth, S. Cliver: R. Copper'. Dept. Ob/Gyn. Univ. of Alabama 8irmingham. OBJECTIYE: To characterize the extent and etiology of decreased bi rthwei ght (BIIT) among infants wi th major congeni ta I anoma lies. STUIlY OESI6II: Infants with a major chromosomal or structural anomaly were Identified from 33.056 liveborn, singletons at 5 medi ca 1 centers from 1982-86. Anoma 1 i es were di agnosed at bi rth or in the neonatal period, and categorized as structural or chromosomal. Gestational age (GA) was based on clinical, ultrasound, and Oubowitz criteria. Fetal growth restriction (FGR) was defined as a birthweight <lOth percentile, and preterm delivery (PTO) as <37 weeks gestation. RESULTS: A major chromosomal or structural anomaly was identified in 402 infants (1.2%); 371 were structural (92%) and 31 were chromosomal. PTD occurred in 170 Infants (42%). The majori ty of these were spontaneous (71%) rather than i ndi cated (29"). The mean GA of both the i ndi cated and spontaneous PTO was 31 weeks . FGR occurred in 19%, and 7.2" were at or below the 3rd percentile. Infants with structural anomalies tended to have higher rates of PTD (43 vs 29%,p.12) and FGR (19.4 vs 9.7%,p . 18) than those with chromosomal anoma 1 i es. The mean GA at del i very, BIIT, and the pro port i on of FGR among infants with chromosomal and various types of structural anomal ;es are presented.

Mean Mean % FGR n GAwks ~ <3rd <4-10th

Chromosomal 31 37.4 2941 IT 6.4 Structural 371 35.8 2507 7.6 11.8

CNS 92 35 .7 2405 12 .0 18 . 5 GI 14 36.9 2416 21.4 7.1 Cardiac 63 37.9 3023 4.8 12.7 Other 202 35.2 2400 5.4 9.4

CONCLUSIOIIS : Although both PTO and FGR contribute to a reduction in BWT in I nfants with congeni ta 1 anoma 1 i es, the majority of reduced BIIT is due to spontaneous PTO rather than FGR. The impact of both of these etiologies is more striking in infants with structural rather than chromosomal anomaH es .

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SPO Abstracts 395

GENETIC AMNIOCENTESIS AND OPERATOR VOLUME. ~ (1), RP Lorenz (1.2). J Kirk (1), Divisions of Maternal Fetal Medicine. Fetal Imaging. and the Reproductive Genetics Program, 1) William Beaumont Hospital, Royal Oak MI and 2) Wayne State University OBJECTIVE: Operator experience (Verjaal. 1981) and # of needle insertions (Lowe. 1978) are related to pregnancy loss after midtrimester genetic amniocentesis. The null hypotbesis is that there were no differences in technical aspects or outcome between genetic amniocenteses done by physicians (HI) doing a large number of referral cases and those done by primary physicians (LO) less frequently. METIIODS: All procedures were done in the Division of Fetal lmaging with sonoiogists' assistance at 15-20 weeks gestation. Only singleton pregnancies planning delivery at our center were studied. RESULTS: During the study period (Jan 1990-Aug 1991), physicians in a genetics referral program (mean 188 ± 46 amnioo/yr/physician)(HI) performed 383 procedures on study patients. and 13 physicians (mean 18 ± 14 amnios/yr/physician)(LO) performed 217 procedures on study patients. The groups differed in 1) indications (p=.05). 2) # of multiple needle insertions (1112.9%; LO 9.2%; p<.(02), and transplacental insertions (16% vs. 24%. p=.03). There were no differences in failed procedures. spontaneous abortions. stiUbirths. preterm births. or NlCU admissions. Power analysis of procedure-related stillbirths (.25% rate, p=.05. power- .8) indicates that we can only exclude an increase of stillbirths of tenfold between these groups. A sample size of 4600 patients in each group is necessary to excluded a twofold increase in procedure related stillbirths. CONCLUSION: Genetic amniocentesis by primary physicians in low volume is associated with an increased rate oftransplacenlai insertions and multiple needle insertions, which may be a risk factor for pregnancy loss. Further research should be undertaken. Until further data are available. the Ob/Gyn Residency Review Committee's educational objective for this procedure and the performance of this procedure by primary physicians are questioned.

352 ' FEASIBILITY AND CYTOGENETIC OUTCOME OF FIRST TRIMESTER AMNIOCENTESIS Q.Jri.Qnx, S. Dahoun·X, Ph. Extermannx, C. DeLozier-Blanchet·x, F. B&guin. Dept Ob/Gyn, Div. Medical Genetics', University Hospital GENEVA, Switzerland

OBJECTIVE: To asses the possibility 01 amniotic fluid sampling for fetal karyotyping during the first trimester of pregnancy. STU DY DESIGN: women undergoing elective first trimester termination 01 pregnancy (TOP) were asked to participate in the study, wich had been approved by the departmental ethics commitee. Written and oral inlormation was given at the pre-hospitalization visit. After consent was obtained, amniocentesis (a single attempt) was performed Iransabdominally with a 22-gauge needle using a freehand technique under continuous ultrasound guidance. We attempted In collect >5 ml of amniotic fluid. TOP was carried out the same morning. Flask and in situ cultures were establishrd in Chang medium; cytogenetic procedures were those routinely used with second trimester amniotic fluid samples. RESUL TS: Irom February to August 1992, 42 amniocentesis were performed in 8 to 12 weeks pregnancies with crown-rump lengths (CRL) from 17 to 66 mm (mean 33, ± 9.7). Fluid was collected in all cases, in amounts from 1 to 17 ml (mean 8 mi. ± 5). In the 6 pregnancies wilh CRL <23 mm, less Ihan 3 ml 01 amniotic fluid volume was obtained. In 14/21 pregnancies wilh CRL from 23 to 35 mm, and in all 15 with CRL >35 mm, at least 5 ml of amniotic fluid was obtained. Fetal heart activity was present in all cases after amniocentesis. 01 the35 samples sent to the Genetics Division, 3 are stili in culture. Of the remaining 32 cases 19 (59%) did not grow, whereas 9 (28%) revealed normal letal karyotypes (6 cases 46, XY; 3 cases 46, XX). In 4 others, (12%) only cytogenetic results of insufficient quantity andlor quality could be obtained. CONCLUSIONS: these preliminary data indicate that fluid sampling is difficult when CRL is 35 mm or less. The amniotic sac, readily visible on ultrasound, tends to collapse after aspiration of various amounts of fluid. In addition, the safety of the pnocedure has not been established. Using standard culture and harvesting techniques we were able In establish the fetal karyotype in only a minority of cases; the more advanced the gestation and the more lIuid obtained, the higher the probability 01 success. This experience, taken together with reports 01 letal anomalies associated with early chorionic villus sampling. indicate that it may be difficult aneVor unsafe to obtain a karyotype at less than 10 weeks of pregnancy.