Pregnancy outcomes following false-positive multiple marker screening tests

Pregnancy outcomes in women with a false-positive midtrimester multiple marker screening test (MMST) were reviewed. A genetic database was used to identify all women > or = age 30 who had a MMST at 15-20 weeks of gestation, a targeted ultrasound, and amniocentesis, and complete pregnancy outcome data. All patients with an abnormal fetal ultrasound (US) or karyotype were excluded. The incidence of adverse outcomes (defined as fetal death, preterm delivery, or a birth weight less than the 10th percentile for gestational age), in those women with a positive MMST (risk of Down's syndrome > or = 1:190) was compared to the incidence of adverse outcomes in control women with negative MMST. Chi-square analysis and Fisher's exact tests were used for comparisons as appropriate. Complete data was available from 1135 women. Seventy-seven percent were over age 35. Two hundred and forty-six women (22%) had a positive multiple marker test. No significant differences in outcomes were discovered after comparisons to controls: fetal death 1 of 246 (0.4%) versus 12 of 889 (1.3%), p = 0.32; preterm delivery 32 of 246 (13.0%) versus 147 of 889 (16.5%), p = 0.17; birth weight less than the 10th percentile, 9 of 246 (3.7%) versus 30 of 889 (3.4%), p = 0.83. Our data suggest that women > or = age 30 with a false-positive MMST and a normal midtrimester obstetrical sonogram are not at an increased risk for adverse pregnancy outcomes in later gestation.     

Etiology and outcome of acute renal failure in elderly patients

OBJECTIVE: To test the usefulness of the fetal transverse cerebellar diameter/abdominal circumference (TCD/AC) ratio in predicting known small-for-gestational-age (SGA) infants. METHOD: The relationship between fetal TCD and AC throughout the second half of pregnancy was investigated in 635 well-dated, normal pregnancies and examined with regard to gestational age and infant birth weight percentiles. RESULTS: One hundred eighteen (19%) fetuses were excluded due to inadequate visualization of the fetal cerebellum. A strong correlation was noted between gestational age determined by the last menstrual period and both fetal TCD (r2 = 0.91338) and AC (r2 = 0.89361) in fetuses with birth weights between the 10th and 90th percentiles (n = 407; mean 14.4, S.D. 1.2). Although the TCD/AC ratio showed a poor correlation with gestational age (r2 = 0.15788), a slight increase was noted during gestation. A TCD/AC ratio greater than 15.5 was present in 80% of SGA infants when measurements were performed within 1 week of delivery. CONCLUSION: Fetal TCD/AC ratio as a gestational age-independent method could improve diagnostic sensitivity and specificity in the early detection of fetal growth abnormalities.     

Impaired growth and risk of fetal death: is the tenth percentile the appropriate standard?

OBJECTIVE: Our purpose was to determine whether the 10th percentile of birth weight for gestational age is appropriate to identify fetuses at risk of death associated with impaired growth. STUDY DESIGN: All live births recorded in Virginia from Jan. 1, 1991, through Dec. 31, 1993, were examined. Percentile growth curves were constructed, and fetal, neonatal, and perinatal mortality rates were calculated for births within various percentile intervals. RESULTS: Significantly elevated fetal mortality was found for birth weights through the 15th percentile. The odds ratio for fetal mortality relative to the baseline for births < or = 5th percentile was 5.6, for the 5th through the 10th percentile 2.8, and for the 10th through the 15th percentile 1.9. These were all significant. CONCLUSION: Fetuses with birth weights between the 10th and 15th percentiles are at a significantly increased risk for fetal death. Therefore the use of the 15th percentile as a diagnostic threshold for the identification of the fetus at increased risk associated with impaired growth is recommended.     

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.     

Weight-for-length reference data for preterm, low-birth-weight infants

OBJECTIVE: To provide weight-for-length reference data for preterm, very-low-birth-weight and low-birth-weight infants. DESIGN: Data from 867 infants (428 boys and 439 girls) in the Infant Health and Development Program, who each were preterm and who had a low birth weight, were used to develop weight-for-length reference data. The Infant Health and Development Program is a national, randomized, clinical trial that included various ethnic groups at 8 sites. At each site, sampling ensured that two thirds of the infants in the study weighed 2000 g or less and that one third of the infants weighed from 2001 to 2500 g at birth. Infants were examined at birth, at 40 weeks' postconception, and at 4, 8, 12, 18, 24, 30, and 36 months' gestation-adjusted age. Gestation-adjusted age was used instead of chronological age from birth to correct for the degree of prematurity. RESULTS: Weight-for-length percentiles are given for lengths at 3-cm intervals ranging from 48 to 100 cm. These percentiles are sex specific and are for a very-low-birth-weight group (< or = 1500 g) and a low-birth-weight group (1501-2500 g). CONCLUSIONS: These data should assist screening for deviations from normal growth and may aid in the early detection of failure to thrive and excessive weight gain in infancy.     

When they grow up: the growth of extremely low birth weight (< or = 1000 gm) infants at adolescence

The growth of 32 extremely low birth weight infants (1000 gm or less) was determined at adolescence. Their height, weight, and head circumference were measured twice in the first year of life and then at ages 2, 3, 5, 8, 10 years, and during adolescence (12 to 18 years). The mean height, weight, and head circumference of the adolescents were at the 50th percentile. Female heights were > or = their mothers; male heights were in the same or greater percentile than those of their fathers. Extremely low birth weight infants experience "catch-up" growth up to and into adolescence and attain predicted biparental genetic height.     

Longitudinal assessment of growth in children born to mothers with human immunodeficiency virus infection

OBJECTIVES: To describe and to evaluate the longitudinal growth of children born to mothers with human immunodeficiency virus (HIV) infection. DESIGN: Measurements of weight, length (measured in infants in a recumbent position) and height (measured in older children in an upright position), and head circumference were documented and evaluated longitudinally using generalized estimating equations in a group of children born to HIV-infected mothers. Children infected with HIV were compared with uninfected children and with National Center for Health Statistics standards. SETTING: Primary care clinic in an urban hospital devoted to the medical care of children born to HIV-infected mothers. PATIENTS: One hundred nine children born to HIV-infected mothers, 59 HIV-infected and 50 uninfected, between birth and 70 months of age. RESULTS: The mean birth weights of both groups were below the 50th percentile. While the mean weight-for-age curve of uninfected children attained the 50th percentile by age 24 months, the mean birth weight-for-age curve of HIV-infected children remained below the 50th percentile. Weight gain became significantly different between the two groups by age 36 months. The mean birth length-for-age curves of HIV-infected and uninfected children was also below the 50th percentile. The mean height-for-age curve of uninfected children attained the 50th percentile by age 40 months, while that of HIV-infected children remained well below the 50th percentile. Linear growth between HIV-infected and uninfected children diverged earlier than weight, becoming significantly different by age 15 months. CONCLUSIONS: Although children born to HIV-infected mothers are born with weight and length below the 50th percentile, uninfected children catch up, while HIV-infected children remain below the 50th percentile and experience an earlier and more pronounced decrease in linear growth (height-for-age) than in weight-for-age.     

Ultrasonographic estimate of birth weight at 24 to 34 weeks: a multicenter study

OBJECTIVE: The study was intended to compare the accuracies of ultrasonographic estimates of birth weights among infants born between 24 and 34 weeks' gestation at 3 tertiary centers. STUDY DESIGN: In this retrospective study subjects were matched for gestational age (1:1); all underwent ultrasonographic examination within 2 weeks of delivery. The estimates of birth weight were obtained according to 26 published regression equations and their accuracies were assessed with the mean standardized absolute error. For each center the equation with the lowest error was selected to generate (1) receiver-operating characteristic curves for an estimate to identify actual weight < 1500 g and (2) prediction limit calculations to determine the estimate that ensures at 70% confidence a birth weight > 1500 g. RESULTS: One hundred seventy-one cases were analyzed at each center. Comparison of the 26 mean standardized errors at each center indicated that (1) the range was rather wide (eg, 89 +/- 87 to 365 +/- 313 g/kg) and (2) 73% (19/26) of the equations had significantly (P < .05) different accuracies. Receiver-operator characteristic curves show that fetal weight estimates of > or = 1600 g at 2 centers and > or = 1700 g at the third center are required to predict actual birth weight < 1500 g. Prediction limit calculation suggests that different fetal weight estimates (> 1600 g at center 1, > 1900 g for the center II, and > 1800 g at center III) are needed to predict actual weight > 1500 g with a 70% accuracy. CONCLUSIONS: Ultrasonographic estimates of weight for preterm infants, as obtained from 26 equations, are characterized by a rather wide range of accuracy; for most of the equations the accuracies of estimates differ markedly among centers.     

Significance of idiopathic preterm birth in relation to previous and future pregnancies

This registry-based cohort study aimed to describe the relationship between pregnancy complications in the first and second pregnancy, focussing on idiopathic and indicated preterm birth of singleton infants in either pregnancy. The cohort consisted of all women living in Denmark with a first singleton birth in 1982 and a second in the period 1982-1987 (13,967 women). The risk of a second preterm birth was not significantly different between women who had an idiopathic or an indicated first preterm birth (15.2 and 12.8% respectively). Adjustment by logistic regression analysis for other risk factors for preterm birth did not influence the relative risk (6.0 before 32 weeks and 4.8 between 32 and 36 weeks) of a second preterm birth subsequent to a first one. Women with idiopathic preterm delivery in their first or second pregnancies give birth to infants with lower birth weight in previous or subsequent pregnancies. Emergency cesarean section in a first term pregnancy was a risk factor for subsequent idiopathic preterm birth.     

Ultrasound fetal biometry charts for a North American Caucasian population

PURPOSE: This study was done to produce enhanced fetal biometry charts and graphs presenting percentile values as a function of fetal age. METHODS: The relationships between the ultrasound measurements of 10 fetal parameters and menstrual age were determined by a cross-sectional study. Data were obtained from 508 to 790 fetuses. Anatomic structures were scanned and measured 3 times during 1 routine sonographic examination. The study group consisted of 1,396 Caucasian women who had normal singleton fetuses with confirmation of menstrual dates by sonography before 14 weeks and for whom complete pregnancy outcome information was available. For each of the 10 parameters, percentile curves were derived for the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles. RESULTS: Ready-to-use fetal measurement charts and graphs are presented in a format giving the percentile values as a function of fetal age. There were no significant differences between male and female fetuses. CONCLUSIONS: These fetal biometry charts and graphs, obtained from a North American Caucasian population, enhance previously published data.     

Human recombinant anti-Rh(D) monoclonal antibodies: improvement of biological properties by in vitro class-switch

The aim of this study was to investigate how intrauterine growth retardation affects body proportions in VLBW infants. The cohort consisted of 135 surviving and 80 deceased preterm infants weighing less than 1250 grams at birth. Gestational age varied between 24 and 36 weeks (mean age 29.7 and 27.5 weeks, respectively). Birth weight was more than 2 SD below the mean birth standard values in 32% of the surviving, and in 27% of the deceased infants. Reduction of weight, length and head circumference at birth was analysed using Z scores based on Swedish birth standards. Z scores of weight, length and head circumference were highly correlated in the surviving and the deceased infants (r = 0.78 to 0.94 and 0.65 to 0.97, respectively). Length was significantly more affected by growth retardation than weight. Weight and head circumference were proportionately reduced. Intrauterine growth retardation influences body proportions in VLBW infants differently than in larger preterm and term infants.     

A standard of fetal growth for the United States of America

The appropriate interpretation of monitored fetal growth throughout pregnancy in individual patients and populations is dependent upon the availability of adequate standards. There is no adequate standard of fetal weight throughout pregnancy that is suitable for patients in the U.S.A. To determine such a standard for infants delivered at about sea level the 10th, 25th, 50th, 75th, and 90th percentiles of fetal weight for each menstrual week of gestation were calculated from 430 fetuses at 8 to 20 menstrual weeks' gestation aborted with prostaglandins and from 30,772 liveborn infants delivered of patients at 21 to 44 menstrual weeks' gestation. Median fetal crown-to-rump lengths and crown-to-heel lengths were derived from measurements of 496 aborted fetuses of 8 to 21 weeks' gestation. Fetal weight correction factors for parity, race (socioeconomic status), and fetal sex were calculated. The derived fetal growth curves are useful for clinical, public health, and investigational purposes.     

Regulatory sequences required for hst-1 expression in embryonal carcinoma cells

OBJECTIVE: To examine the relationship of subfertility with miscarriage, low birth weight, and preterm delivery. DESIGN: Comparison of time to pregnancy distributions between pregnancies that had different outcomes. Three comparisons were made: (a) miscarriages with live births; within live births, (b) low birth weight infant (up to 2,500 grams) or not low birth weight; (c) preterm birth (37 weeks or less) or not preterm. Cox regression was used to adjust for covariates. POPULATION: All first pregnancies were analyzed from the National Child Development Study, a large survey of young adults aged 33 years, which is nationally representative of the British-born population. MAIN OUTCOME MEASURES: The distribution of the time taken to conceive (time to pregnancy), miscarriage, birth weight, and preterm delivery. RESULTS: Pregnancies that ended in miscarriage tended to take 23% longer to conceive, after adjustment for the other variables. Pregnancies that resulted in preterm delivery tended to take 15% longer to conceive. There was no statistically significant association with low birth weight. CONCLUSIONS: Delay in time to conception is a risk factor for poor obstetric outcome, irrespective of medical intervention.     

Doppler velocimetry determined redistribution of fetal blood flow: correlation with growth restriction in diamniotic monochorionic and dizygotic twins

OBJECTIVE: Our purpose was to study fetal growth and blood flow distribution in diamniotic monochorionic compared with dizygotic (diamniotic dichorionic) twins by use of Doppler velocimetry of the umbilical artery and middle cerebral artery. STUDY DESIGN: Study candidates were divided into group A, consisting of 33 pairs (66 fetuses) of diamniotic monochorionic twins, and group B, 50 pairs (100 fetuses) of diamniotic dichorionic twins. Diamniotic monochorionic placentation was confirmed by microscopic placental examination for group A. Diamniotic dichorionic placentation was ensured for group B by selecting only twins with different-sex pairs (dizygotic twins). Targeted ultrasonography with biometry was performed in each twin, and Doppler recordings of the umbilical artery and middle cerebral artery were obtained. Waveforms were analyzed and the systolic/diastolic ratio, the resistance index, and a measure of blood flow redistribution (brain-sparing effect), the cerebral/placental ratio, was calculated for each fetus. Growth status at birth was assessed by the number of small-for-gestational-age infants (< or = 10th percentile), low-birth-weight infants (< or = 25th percentile), and percent of growth discordance between twins. Intertwin differences were assessed by delta values (value of larger twin minus value of smaller twin). RESULTS: Diamniotic monochorionic compared with dizygotic twins demonstrated a significantly greater probability of blood flow redistribution. For the study population as a whole, the brain-sparing effect was noted in 67% of small-for-gestational-age babies and only 7% of non-small-for-gestational-age infants (p < or = 0.001). For the diamniotic monochorionic pregnancies blood flow redistribution occurred in 6 of 10 small-for-gestational-age infants (60%) and 6 of 46 non-small-for-gestational-age infants (13%). In the diamniotic monochorionic group small-for-gestational-age compared with non-small-for-gestational-age infants were more likely to show blood flow redistribution, which was the result of significantly decreased resistance in the middle cerebral artery and significantly increased resistance in the umbilical artery. Small-for-gestational-age infants (< or = 10th percentile) occurred much less frequently in the dizygotic group. Two of two small-for-gestational-age infants in the dizygotic group showed blood flow redistribution. Although the extremes of birth weight were more common in the diamniotic monochorionic group, both groups had relatively large numbers of small babies with birth weights in the lower 25th percentile (50.0% for diamniotic monochorionic and 44.0% for dizygotic twins, not significant). However, 42.3% (11/26) of diamniotic monochorionic twins who were in the low-birth-weight group showed blood flow redistribution compared with only 3.3% (1/30) whose birth weights were > or = 25th percentile (p < or = 0.001). In the dizygotic twins 10% of lower-birth-weight infants redistributed blood flow compared with 1% in the higher-birth-weight group, a nonsignificant difference. Diamniotic monochorionic compared with dizygotic twins were delivered earlier (32.9 weeks vs 34.8 weeks, p < or = 0.001), were smaller (1832 gm vs 2304 gm, p < or = 0.001), showed higher birth weight discordance (29.8% vs 14%, p < or = 0.05), and had greater numbers (19.7% vs 2.3%, p < or = 0.01) of infants at < or = 10th percentile birth weight. CONCLUSIONS: Diamniotic monochorionic twins from the lower-birth-weight groups more often show blood flow redistribution compared with dizygotic twins of similar low birth weights. Placental vascular connections and the attendant hemodynamic changes in the fetuses of diamniotic monochorionic twins probably account for this difference. Brain-sparing events occur commonly without clinical twin transfusion syndrome in this group. These findings have implications for management.     

Plasma concentrations of fibrinogen and factor VII in adult life and their relation to intra-uterine growth

To examine the relation between fetal development and plasma concentrations of fibrinogen and factor VII in adult life we followed up 202 men and women, now aged around 50 years, who had been measured in detail at birth. Plasma concentrations of fibrinogen were related to weight and abdominal circumference at birth. In men, after adjustment for cigarette smoking and current obesity, plasma concentrations of fibrinogen fell by 0.12 g/l (95% CI 0.05-0.19) for each pound increase in birthweight and by 0.10 g/l (95% CI 0.03-0.17) for each inch increase in abdominal circumference. In contrast, analysis of the data for women showed no statistically significant relation between plasma fibrinogen concentration and weight or abdominal circumference at birth. No relation was seen between concentrations of factor VII and measurements made at birth in either sex. These findings suggest that, in men, reduced growth of the liver in fetal life has a long-term influence on fibrinogen metabolism.     

Use of mivacurium in orthopedic surgery: comparison of 2 different-dose inductions

OBJECTIVE: To evaluate the postnatal growth of full-term infants with fetal growth retardation (FGR) syndrome and their subgroups (disproportionate and proportionate) after six months of delivery. METHODS: This is a prospective follow-up study of 200 full-term gestations. We compare 100 FGRs (34 cases of FGR-disproportionate and 66 FGR-proportionate) infants against 100 normal infants/controls. At the sixth months of postnatal life, the infants were subjected to a standard paediatric evaluation and examination. RESULTS: At the sixth months of postnatal life, the infant weight was 7.183 g +/- 727 in the FGR group vs. 8.019 g +/- 823 in the control group, p < 0.001. 31% of FGR infants were found under the 10th percentile value as read for the 6th months standard, whereas the same value was detected in only 3% of control infants, p < 0.001. Likewise, 38% of FGR cases were under the 10th percentile of height versus 7% of control cases, p < 0.001. Proportionate FGR infants showed a higher increase of height in comparison to those from a disproportionate group (17.3 cm +/- 1.4 vs. 15.5 cm +/- 3.4, p < 0.05). A negative correlation was found between neonatal ponderal index (NPI) and weight gain (R = -0.16, p < 0.05). CONCLUSIONS: Six months after delivery, weight and height were lower in FGR infants than in controls. At that age, disproportionate and proportionate FGR infants had similar weight and height, being the height catch-up more significant in proportionate ones.     

How accurate is fetal biometry in the assessment of fetal age?

OBJECTIVE: The purpose of the study was to assess the accuracy of fetal biometry in the midtrimester of pregnancy in the assignment of fetal age. STUDY DESIGN: A total of 152 singleton, 67 twin, and 19 triplet gestations resulting from in vitro fertilization with ultrasonographic fetal biometry from 14 to 22 weeks made up the study population. A gestational age prediction equation was derived from singletons with the use of stepwise linear regression. This equation was compared with 38 previously published equations and then applied to the twin and triplet populations. RESULTS: Head circumference was the best predictor of gestational age (random error [SD] 3.77 days). Addition of abdominal circumference and femur length to head circumference improved the accuracy of the dating equation (random error 3.35 days). Most dating formulas had systematic errors of <1 week. The systematic error was -0.32 day for averaging the singleton-based predictions for twins and -1.26 days for triplets. CONCLUSIONS: Gestational age assessment with the use of fetal biometry from 14 to 22 weeks is accurate for singleton, twin, and triplet gestations.     

Postnatal changes of leptin levels in full-term and preterm neonates: their relation to intrauterine growth, gender and testosterone

The present study was carried out to investigate leptin levels in arterial and venous cord serum and in amniotic fluid in full-term infants at birth and on the 5th postnatal day to define the relationship of leptin to intrauterine growth rate, gender and early postnatal life. The relation of weight gain to serum leptin levels in male preterm infants was determined measuring leptin concentration weekly in the first 5 postnatal weeks. Testosterone levels were determined simultaneously to explore a possible relationship between leptin and testosterone concentrations. Fifty-three term newborn infants with mean birth weight and gestational age of 3,419 g (range 2,150-4,480) and 38.9 weeks (range 36-41) and 19 preterm male infants (mean birth weight and gestational age were 1,416 g (770-1,800) and 30.2 weeks (26-35) were enrolled into the study. Leptin and testosterone levels were determined by radioimmunoassay. It was demonstrated that serum leptin levels were markedly elevated in the cord blood without discernible arteriovenous differences. Cord blood leptin was found to correlate with birth weight (r = 0.40, p < 0.002), weight to length ratio (r = 0.40, p < 0.002) and body mass index (r = 0.35, p < 0.005). It was significantly lower in boys as opposed to girls (p < 0.01) and there was an apparent fall by the 5th postnatal day (p < 0.001). Amniotic fluid contained leptin in much less concentration than cord blood and it proved to be independent of intrauterine growth or gender. Serum leptin concentration in preterm infants at 1 week of age was significantly lower compared with term infants (p < 0.002) and it increased progressively with age (p < 0.01). An inverse relationship was found between leptin and testosterone level (r = -0.358, p < 0.01) and a positive correlation between leptin level and weight/height ratio (r = 0.674, p < 0.01). It is concluded that leptin derived either from placenta or fetal adipose tissue may be involved in regulating fetal growth and development and it may be related to energy intake, storage and expenditure. In preterm male infants serum leptin concentration increases with postnatal weight and testosterone may suppress leptin synthesis.     

A microscopic analysis of cut-bevel versus pencil-point spinal needles

OBJECTIVE: Our purpose was to establish new nomograms for the birth weight of twins on the basis of accurate methods to validate gestational age. STUDY DESIGN: The medical records of 1632 consecutive twin gestations delivered between 1984 and 1996 were reviewed. Only pregnancies induced by ovulation induction techniques or that were measured ultrasonographically for crown-rump length during the first trimester were included. Excluded were those whose fetuses (one or both) were stillborn, or if the mother smoked, had a significant chronic illness, or was prescribed any regular medications. The study comprised 520 twin pregnancies at 28 to 41 gestational weeks at delivery. RESULTS: The median and 10th and 90th percentile birth weight curves were calculated for the studied twins and plotted against previously reported singleton nomograms. Fetuses of twin pregnancies were found to be growth restricted in comparison with previously reported singletons throughout the third trimester. This trend became more evident after the thirty-fourth to thirty-sixth weeks. CONCLUSIONS: We recommend these novel birth weight nomograms for clinical use in the management of twin pregnancies.