Does excessive adenosine 5''-triphosphate formation in cells lead to malignancy? A hypothesis on cancer

PROBLEM: Neonatal outcome of in vitro fertilization (IVF) pregnancies has been described by different authors, but several issues have yet to be resolved. The aim of the present study was to evaluate neonates conceived in vitro and to direct special attention to neonatal morbidity and prevalence of minor abnormalities. The information that has been accumulated so far is scant. METHOD: The first 100 babies conceived in vitro, and subsequently born in our institute, were investigated and compared with the general, spontaneously conceived newborn population. All infants were examined by a senior neonatologist, and the data that were recorded included gestational age at delivery, birth weight, gender, major malformations, minor congenital abnormalities, neonatal mortality, and neonatal morbidity (including asphyxia, jaundice, meconium aspiration, hypoglycemia, and hypocalcemia). RESULTS AND CONCLUSIONS: The data indicate that the IVF neonates assessed had a higher rate of low birth weight (37%), twinning (30%), and preterm birth (20%) in comparison with the general reference population (p < 0.05). However, no differences were encountered either in the rate of small for gestational age infants or the incidence of major malformations and minor abnormalities between these groups of newborns. The overall neonatal morbidity in IVF babies was found to exceed that of the general population. Nevertheless, at birth, there were no clinical pathognomonic signs typical of IVF babies, although more detailed metabolic, endocrine, and neurobehavioral studies are still required to confirm that newborns conceived in vitro do not differ from those conceived spontaneously in any of these respects.     

Mainland China, Taiwan and the Hong Kong Region: the Second Medical Education Conference

OBJECTIVE: Our objective in this study was to evaluate decreased weight/length ratio as a correlate of perinatal morbidity in twins. STUDY DESIGN: Rates of weight/length ratio less than 10% (low WL) were compared in 986 neonates from twin gestations and 4929 matched singletons. Low WL was compared with birth weight less than 10% (SGA) and 25% birth weight discordance as a marker for perinatal depression and neonatal mortality. RESULTS: Both SGA (42% vs 8%) and low WL (38% vs 8%) occurred more commonly in twins. Low WL was a better correlate of depression and mortality than SGA or 25% birth weight discordance. After adjustment for major anomalies, prematurity, and low WL, perinatal morbidity in twins and singletons did not differ. CONCLUSIONS: Low WL, a marker of asymmetric growth restriction, is a better marker for perinatal morbidity in twins than SGA or 25% discordance. Twins and singletons have similar rates of perinatal morbidity and mortality after adjustment for anomalies, prematurity, and growth restriction.     

Lower risks of adverse outcome in twins conceived by artificial reproductive techniques compared with spontaneously conceived twins

The outcomes of twins conceived by 136 women after medical assistance (MA) such as ovulation induction with or without assisted reproductive techniques, and twins conceived spontaneously (SP) by 72 women were compared. All 208 women were monitored from < 20 weeks gestation; they all delivered at > or = 24 weeks gestation. The chorionicity of the placenta was diagnosed antenatally and confirmed after delivery. There were 10 perinatal deaths; the physical and neurological status of the remaining 406 infants was assessed at 1 year of corrected age. There were no differences in gestational age at birth, the birth weights of the larger and smaller twins, the birth weight discordance, or the incidence of life-threatening major malformations between groups. Adverse infant outcomes, such as death, cerebral palsy and mental retardation occurred in nine (3.3%) of 272 MA twins compared with 12 (8.3%) of 144 SP twins (P < 0.05). The placenta was monochorionic in only three (2.2%) of 136 MA twin pregnancies compared with 41 (57%) of 72 SP twin pregnancies (P < 0.001). Of the 21 infants with adverse outcomes, nine had monochorionic placentas. Thus, the risk of an adverse outcome was 2.8-fold higher (95% confidence interval (CI) 1.2-6.4) in monochorionic twins than in dichorionic twins (10 versus 3.7%; P < 0.05). There was no difference in the incidence of adverse infant outcomes between SP (4.8%) and MA (3.4%) twins with dichorionic placentas. These findings suggest that ovulation induction in itself was not associated with an adverse outcome of twin pregnancies. The lower frequency of monochorionic placentas in MA twins may have been responsible for the lower risk of an adverse outcome in MA twins.     

Human herpesvirus-6: a new member of the herpesvirus family, a threat to AIDS, organ-transplanted and other immune deficient patients

OBJECTIVE: The purpose was to evaluate a low weight to length ratio as a correlate of perinatal morbidity and mortality. STUDY DESIGN: Data from the Collaborative Perinatal Project for infants of 34 weeks' gestation or more were evaluated. Associations between the weight to length ratio of < 10% (low weight to length) and birth weight of < 10% (small for gestational age) by gestational age and gender, perinatal depression, dysmaturity, cerebral palsy, and neonatal mortality were evaluated. RESULTS: A low weight to length ratio and small for gestational age status were associated with most markers of perinatal morbidity and mortality in term and preterm infants. In infants not small for gestational age, a low weight to length ratio was associated with increased morbidity and mortality (relative risk of 1.9 to 4.2) in term infants, and with perinatal depression (relative risk of 2.9) in preterm infants. Logistic regression found low weight to length ratio was a better independent correlate than small for gestational age status for all markers assessed and found low weight to length ratio was significantly associated with all morbidity and mortality markers in infants not small for gestational age. CONCLUSION: Low weight to length ratio, a marker for asymmetric growth restriction, is correlated with perinatal morbidity, even in infants not small for gestational age.     

Obstetric and perinatal outcome of pregnancies following intracytoplasmic sperm injection

The aim of this study was to describe the obstetric and perinatal outcome for births following intracytoplasmic sperm injection (ICSI). Of 210 infants born, 140 were singletons and 70 were twins. There were no triplets or higher births. The multiple birth frequency was 20%. Overall, 17% of deliveries were preterm, although for singleton pregnancies the incidence was reduced to 9%. The median birth weight of all live born infants was 3168 g and singletons 3470 g. Of all infants, 17% had a low birth weight (<2500 g) and 2% had a very low birth weight (<1500 g). Two major malformations occurred in two singleton children and four minor malformations occurred in four children. This was within the range of expected values in Sweden. Karyotyping was performed in 58 pregnancies. All of them were normal. The perinatal mortality was 0.5%. In conclusion, in this observational study from Sweden of the first infants born after ICSI in our programme, the incidence of multiple births, preterm births, low birth weight babies and congenital malformations was low compared with other series of in-vitro fertilization pregnancies not associated with ICSI.     

Perinatal outcome of pregnancies after assisted reproduction: a case-control study

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.     

Neonatal morbidity and mortality associated with triplet pregnancy

OBJECTIVE: To compare neonatal morbidity and mortality in a large cohort of triplet pregnancies with singleton and twin neonates managed at a single tertiary center over a short time. METHODS: Records from all triplet pregnancies managed and delivered from 1992 to 1996 were reviewed for neonatal outcome data. Pregnancies delivered before 20 weeks' gestation and neonates with lethal congenital anomalies were excluded. The comparison group comprised all singleton and twin neonates managed in the same neonatal intensive care unit (NICU) during the same period. RESULTS: During the 5-year period, 55 triplet pregnancies and their resulting 165 neonates were managed and delivered at this center. Their outcomes were compared with those of 959 singleton and 357 twin neonates born at similar gestational ages. The median gestational age at delivery for triplets was 32.1 weeks, and 149 of the 165 infants were admitted. Sixteen triplet neonates were not admitted to our neonatal intensive care unit, 12 because of previable gestational age, three because of stillbirth, and one because of a lethal congenital anomaly. The crude perinatal mortality rate in triplets was 121 per 1000 births, and there was no significant difference in outcome based on triplet birth order. There were no significant differences in survival rates between singleton, twin, and triplet neonates, with an overall neonatal survival of 95%, 95%, and 97%, respectively. The only significant differences in morbidity were an increased incidence of mild intraventricular hemorrhage (relative risk [RR] 6.20; 95% confidence interval [CI] 2.64, 14.61), mild retinopathy of prematurity (RR 20.05; 95% CI 3.59, 111.79), and severe retinopathy of prematurity (RR 46.69; 95% CI 6.25, 348.85) in triplets compared with singletons, and severe retinopathy of prematurity (RR 6.83; 95% CI 1.24, 37.56) in triplets compared with twins. CONCLUSION: When stratified by gestational age, triplet neonates delivered at 24-34 weeks' gestation have similar outcomes as singleton and twin neonates, with the only clinically significant difference being an increased incidence of retinopathy of prematurity in triplets.     

The effect of maternal smoking on birth weight in twin pregnancies

Information on 869 076 singletons and 17 566 twins, born during the period 1983-1991, was obtained from the Swedish Medical Birth Registry. Data on birth weight, gestational duration, vital status, and maternal smoking habits during pregnancy were analyzed in order to investigate whether twinning potentiates the effect of maternal smoking on birth weight and perinatal mortality. The individual birth weights were expressed as percentages of mean birth weight, where mean birth weights of singletons and twins were calculated separately. The birth weight reducing effect of maternal smoking was found to be of the same magnitude among twins and singletons weighing > 90% of mean birth weight. For infants weighing < 90% of mean birth weight, maternal smoking had a significantly stronger effect on birth weight among singletons than among twins. When gestational duration was taken into consideration, this difference was less pronounced. The effect of maternal smoking on gestational duration was stronger among singletons than twins. The smoking-related risk increase of perinatal death was of about the same magnitude among twins and singletons.     

Causes of perinatal mortality in twins

The author analyses perinatal mortality in 244 twin pregnancies. In 80% the twins' Apgare score at birth was 10 to 8 and neonatal mortality in this group 1.26%. The slightly asphyxial group (Apgar 7 to 4) comprised 62 (38.75%) twins and the neonatal mortality in this group was 14.51%. There were 20 (12.5%) severely asphyxial (Apgar 3 or less) twins, their neonatal mortality amounting to 80.0%. Out of 193 twins weighing at birth less than 2500 g, 45 (23.31%) died, while in the twins weighing more than 2500 g there was not a single death. The perinatal mortality of twins up to the 37th week of pregnancy amounted to 17.37% and from the 38th week of pregnancy to 1.22%. The mean duration of pregnancy in twins was 38.1 +/- 2 SD 6.3 weeks. The most frequent cause of death in twins has proved to be immaturity and asphyxia at birth, leading to the development of hyaline membranes (80.0%). Other causes were far less frequent. The author concludes that in the perinatal mortality of twins their vitality at birth (assessed by the Apgar score), birth weight, and the duration of pregnancy play an important role.     

Purification and characterization of a low-molecular-weight bovine kidney acid phosphatase

To investigate changes in cerebral palsy birth prevalence and perinatal mortality rate by different gestational age groups, 1979-86, cerebral palsy cases in eastern Denmark were identified from the Danish Cerebral Palsy Register, and information on birth and mortality rates was sought in the Danish Medical Birth Register. From 1979-82 to 1983-86, the birth prevalence of cerebral palsy increased from 2.6 to 3.0 per 1000 (P < 0.05). The rate for infants of 31 weeks' gestation or more did not change, whereas a significant increase was observed in infants below 31 weeks (85-123 per 1000, P < 0.05). In the same periods, perinatal mortality in eastern Denmark decreased significantly from 8.6 to 7.8 per 1000. The decrease in stillbirth rate was significant in all subgroups of gestational ages except in those of 28-30 weeks' gestation. The early neonatal mortality rate decreased significantly only in infants below 31 weeks (282-239 per 1000, P < 0.05). Thus, in eastern Denmark, cerebral palsy birth prevalence has increased from birth-year period 1979-82 to 1983-86 because of an increased rate in preterm infants below 31 weeks, who at the same time had a reduced risk of early neonatal death.     

Infants conceived using in-vitro fertilization do not over-utilize health care resources after the neonatal period

Health outcomes during the first year for 95 infants born following in-vitro fertilization (IVF) were compared with those of 79 naturally conceived controls whose mothers were of identical parity and similar age. Primigravid women were enrolled prospectively at 30 weeks gestation, perinatal and neonatal data were collected during pregnancy and following birth, and details of health care resource use were obtained from mothers at 4 and 12 months. Median (range) number of medical problems during the first year tended to be less for IVF infants, 4 (0-41) versus 5 (0-12) (P = 0.07), whilst total number of visits to health care workers was similar for IVF and control infants, 19 (2-47) versus 19 (1-47). IVF infants were more likely to have an excessive number of visits to Early Childhood Health Care Centres [odds ratio (OR; 95% confidence interval, CI) = 2.44 (1.11-5.56)], but less likely to have an excessive number of visits to general medical practitioners [OR = 0.45 (0.22-0.93)] and other health care workers [OR = 0.48 (0.23-0.99)]. These data provide some degree of reassurance about medium-term health outcomes for children conceived using IVF. Although they are more likely to utilize the resources of neonatal intensive care units, IVF infants do not appear to have an increased number of medical problems or to over-utilize health care resources during the remainder of their first year of life.     

Births following oral contraceptive failures

Neonatal outcome was studied in 108 infants conceived while their mothers were taking oral contraceptives. The infants tended to be born to younger, less educated mothers and were more likely to have been exposed to hormonal pregnancy tests. Ten newborns were malformed; 8 of these were males. One was anencephalic, and 1 infant had Down's syndrome. There was also a significantly large number of twins and an excess of perinatal mortality. These results are similar to those of previous studies, showing a small but increased risk of adverse outcome in infants born after oral contraceptive failure.     

Children conceived by in vitro fertilisation after fresh embryo transfer

AIMS: To compare the outcome in in vitro fertilisation (IVF) children (after fresh embryo transfer) from multiple and singleton births with one another, and with normally conceived control children. METHODS: A cohort of 278 children (150 singletons, 100 twins, 24 triplets and four quadruplets), conceived by IVF after three fresh embryos had been transferred, born between October 1984 and December 1991, and 278 normally conceived control children (all singletons), were followed up for four years after birth. They were assessed for neonatal conditions, minor congenital anomalies, major congenital malformations, cerebral palsy and other disabilities. Control children, all born at term, were matched for age, sex and social class. RESULTS: The ratio of male:female births was 1.03. Forty six per cent of IVF children were from multiple births; 34.9% were from preterm deliveries; and 43.2% weighed less than 2500 g at birth. The IVF singletons were on average born one week earlier than the controls, weighed 400 g less, and had a threefold greater chance of being born by caesarean section. The higher percentage of preterm deliveries was largely due to multiple births and they contributed to neonatal conditions in 45.0% of all IVF children. The types of congenital abnormalities varied: 3.6% of IVF children and 2.5% of controls had minor congenital anomalies, and 2.5% of IVF children and none of the controls had major congenital malformations. The numbers of each specific type of congenital abnormality were small and were not significantly related to multiple births. IVF children (2.1%) and 0.4% of the controls had mild/moderate disabilities. They were all from multiple births, including two children with cerebral palsy who were triplets. CONCLUSIONS: The outcome of IVF treatment leading to multiple births is less satisfactory than that in singletons because of neonatal conditions associated with preterm delivery and disabilities in later childhood. A reduction of multiple pregnancies by limiting the transfer of embryos to two instead of three remains a high priority.     

Five-year follow-up after balloon pulmonary valvuloplasty

We hypothesized that gender and intrauterine growth retardation (IUGR) have greater effects than birth order on mortality and morbidity rates of very low birth weight (< 1501 gm) twins. Neonatal data were collected on 44 pairs of twins born alive between January 1984 and December 1987. Birth weight was 1018 +/- 289 gm and gestational age was 28.1 +/- 2.5 weeks. The male/female ratio was 46:42; 24 infants had IUGR, and 64 were appropriate in size for gestational age. Of the 88 infants, 61 (69%) survived. Birth order had no effect on outcome. Female twin pairs had a longer gestation than either male twin pairs or twins with discordant sex (29.2 +/- 2.5 weeks vs 27.4 +/- 2.0 weeks and 27 +/- 3 weeks, respectively; p < 0.002). They also had a lower mortality rate (14% vs 47% and 25%; p < 0.001) and a lower incidence of bronchopulmonary dysplasia (22% vs 57% and 50%; p < 0.02). Infants with IUGR had an increased mortality rate (50% vs 23%; p < 0.02) and an increased sepsis rate (61% vs 25%; p < 0.02) compared with infants with appropriate size for gestational age who were matched for gestational age. Multiple logistic regression analysis to assess the independent effects of gestational age, gender, and IUGR on mortality rate, bronchopulmonary dysplasia, and intraventricular hemorrhage revealed that gestational age was the most significant contributor to all three outcome variables; IUGR contributed to an increased mortality rate, and male gender contributed to the occurrence of bronchopulmonary dysplasia.     

Expression of HER-2/neu oncogene in normal, hyperplastic, and malignant endometrium

The development of new technologies in neonatal intensive care which appeared this last decade increased the viability of premature newborns and contributed to the increase in the number of admissions of very low birth weight (VLBW) newborns in the intensive neonatal care services (12.6% of admissions in 1987, 15.2% in 1996). In a retrospective epidemiology survey in French speaking Belgian Community, we collected the data of 1521 newborns whose birth weight was under 1500 g, from January 1990 to December 1994, in order to improve our knowledge or regional mortality and morbidity rates and to estimate the impact of new procedures. We do not notice any variation of annual mortality (+/- 20%), nor of morbidity (sequelae risks to survivors at the departure of the hospital +/- 23%) on the global population during the survey period. However the mortality of infants born between 30 and 33 weeks drops dramatically (17% in 1990, 3.6% in 1994). As it has been demonstrated in randomised surveys, we recover the beneficial effect of antenatal corticotherapy which allows us to reduce to more than 50% the mortality of newborns from treated mothers (11% mortality versus 24%). In comparison to figures of international literature, our survival rate without sequelae is at least 10% lower than Américan results for infants whose birth weight is < 1000 g and at least 5% lower for infants between 1000 and 1500 g. In conclusion, although the introduction of surfactant and high frequency ventilation during this period, mortality rate of VLBW infants doesn't seem to decrease significantly from 1990 to 1994. However, multivariate statistical study of predictable mortality and morbidity factors need to be performed in order to define or promote preventive strategy.     

A common pathway mediates retinoic acid and PMA-dependent programmed cell death (apoptosis) of neuronal cells

To assess the maternal and neonatal risk associated with high-order cesarean sections, a case-control study was carried out in two university affiliated maternity wards. The outcome of 154 pregnancies of women undergoing cesarean section for the 4th time or more was compared with 148 women sectioned for the 2nd or 3rd time and 132 women of similar age and parity after spontaneous birth. The main outcome measures were maternal operative and postoperative morbidity and neonatal prematurity and its complications, Apgar scores, and the need for intensive care. Women undergoing multiple (> or = 4) cesarean sections had significantly more intra-abdominal adhesions (P < 0.0001) than women sectioned for the 2nd or 3rd time. However, the time interval from incision to delivery and the total duration of operation were similar. The postoperative course was not adversely affected by multiple cesarean sections. A high incidence (16.2%) of preterm cesarean deliveries was noted in the study group. This was due to non-elective repeat cesarean delivery rather than to poor timing of scheduled cesarean sections. The significantly increased (P < 0.05) need for neonatal intensive care was explained by the higher occurrence of prematurity. Low Apgar scores (< or = 7) at 1 and 5 min were significantly (P < 0.01) related to multiple cesarean sections, even after controlling for the effect of gestational age. We conclude that multiple cesarean sections pose little risk for the mother, but may be associated with increased neonatal risk, attributed mainly to preterm non-elective cesarean sections.     

Multiples births: a continuing problem with assisted reproductive techniques

Assisted reproductive techniques (ART) such as in vitro fertilisation (IVF), ovulation induction and superovulation followed by insemination have caused a sharp increase in multiple birth prevalence rates. The perinatal morbidity of multiple birth infants is high because of the high incidence of premature birth. The social and psychological problems of multiple birth families are also considerable. In 1990 high-order multiple births were mainly the result of IVF. Although the number of IVF treatments has increased more than the number of other ART treatments, nowadays high-order multiple births are predominantly caused by superovulation. Since 1990 the number of high-order multiple births has stabilised, but the recent sharp increase in ART twins results in a further rise in births of severely preterm ART infants. More restraint should be practised in superovulation treatments to bring down the number of (high-order) multiple births.     

Risks of subsequent pregnancies on mother and newborn in female heart transplant recipients

BACKGROUND: Female heart transplant recipients are able to carry pregnancies successfully. This study evaluates the effect of subsequent pregnancies on newborn and maternal outcomes and graft survival. METHODS: Subjects were identified through a previously reported multicenter study, case reports from literature review, and recipients entered in the National Transplantation Pregnancy Registry. A retrospective analysis was completed of 35 heart transplant recipients with first pregnancies (FP) and 12 who had one or two additional pregnancies (P>1). Newborns were assessed for gestational age, neonatal birth weight, and complications. Maternal data included pregnancy outcome, peripartum complications, including infection and rejection, current graft function, and recipient survival. RESULTS: Forty-seven pregnancies (35 FP and 12 P>1) from 35 heart transplant recipients were studied. FP outcomes included 26 live births (one set of twins), four miscarriages, and six therapeutic abortions, whereas P>1 outcomes included 11 live births (one set of twins), and two miscarriages. There was no significant difference between mean birth weights (2353+/-986 gm vs 2588+/-521 g, P>1 vs FP; mean+/-SD; p=NS) or prematurity incidence (<37 weeks; 50% vs 40%; p=NS) for the live-born infants. Compared with the FP group, there was a trend toward increased neonatal complications in P>1 (40% vs 12%; p=NS). Complications were significantly more common in premature newborns compared with full-term newborns (33% vs 5%; p < 0.05). No structural malformations were identified in the live-born infants. Maternal complication rates were the same in both groups (40%). Of 28 recipients available for follow-up, the maternal survival rate was 75% for the FP group and 89% for the P> group. Mean rejection rate per year was slightly increased after pregnancy in the P>1 group. Surviving recipients had similar graft function by echocardiographic left ventricular ejection fraction. CONCLUSIONS: Post-heart transplantation pregnancies often have successful outcomes, but there is a high incidence of prematurity and low birth weight. Subsequent pregnancies do not seem to significantly increase the incidence of complications in either the newborn or mother or increase graft rejection or failure. Larger studies of posttransplantation pregnancies may provide more definitive information.     

Combined effects of antenatal corticosteroids and surfactant supplementation on the outcome of very low birth weight infants

Antenatal corticosteroids in preterm pregnancy may result in the reduction of the incidence of respiratory distress syndrome (RDS) and neonatal mortality. It is well known that postnatal use of surfactant in very low birth weight (VLBW) infants with RDS results in decreased neonatal morbidity and mortality. To evaluate the additive beneficial effects of combined antenatal corticosteroids and postnatal use of rescue surfactant on the outcome of VLBW infants, we retrospectively reviewed 286 maternal/infant charts of preterm infants with gestational ages 23 to 32 weeks and birth weights 501 to 1500 gm who were born at our institution from 1991 through 1994. Of the 87 (30%) infants who were treated with corticosteroids before birth, 41 (47%) had RDS, and of the 199 (70%) infants who were not treated with corticosteroids before birth, 162 (81%) had RDS (p < 0.001). The infants who had RDS and who were treated with corticosteroids before birth had a decreased incidence of pulmonary air leaks and a decreased need for diuretic therapy. In addition, they had a significant reduction in O2 requirement and ventilator settings as reflected by FIO2, mean airway pressure, ventilator rate, O2 index, and A-aDO2 before they received the first dose of rescue surfactant (p < 0.05 to p < 0.01) in contrast to other VLBW infants who had RDS and who were not treated with corticosteroids before birth. We conclude that antenatal corticosteroid therapy in threatened premature labor combined with the use of postnatal rescue surfactant is associated with a decreased incidence of RDS and may be beneficial for reducing the severity of RDS and improving the eventual outcome of VLBW infants.     

Effect of Tissucol on connective tissue matrix during wound healing: an immunohistochemical study in rat skin

OBJECTIVE: Our goal was to identify prenatally available parameters that correlate with neonatal outcome and could be used for predicting such outcome in the extremely low-birth-weight pregnancy. STUDY DESIGN: From 1990 through 1995, obstetric and neonatal data of live-born nonanomalous singleton infants with birth weights between 400 and 1000 gm were reviewed. Only cases in which ultrasonographic biometry, including biparietal diameter, abdominal circumference, and femur length, was performed < or =3 days before delivery were included. Overall survival (defined as alive at discharge) and survival without specific severe neonatal morbidities (namely, retinopathy of prematurity [stage 3 or 4], intraventricular hemorrhage [grade 3 or 4], periventricular leukomalacia, chronic lung disease, and deafness) were ascertained. The best combination of prenatal parameters for the prediction of overall survival and survival without severe morbidity was determined by backward stepwise logistic regression analyses. RESULTS: The most significant prenatal predictors of overall survival were the obstetric estimate of gestational age and the abdominal circumference (chi2 = 11.8036, p = 0.0006 and chi2 = 8.1862, p < 0.005, respectively). Survival without severe morbidity was also predicted by the same combination of parameters (chi2 = 21.9079, p = 0.0001 and chi2 = 6.538, p = 0.01, respectively). The estimated fetal weight was not a significant independent predictor of either category of outcome (chi2 = 0.1249, p = 0.72 and chi2 = 0.0361, p = 0.85, respectively). On the basis of the regression formulas, curves displaying the probabilities of overall survival and survival without severe morbidity with any combination of gestational age and abdominal circumference were developed. CONCLUSION: The combination of gestational age and the abdominal circumference measurements appears to be superior to any combination that included estimated fetal weight data for predicting neonatal outcome in the neonates weighing < or =1000 gm. We developed a mechanism for predicting neonatal outcome in this weight category on the basis of prenatally available parameters. This information could prove useful for both parental counseling and obstetric decision making.