Miscarriage diagnosis and gestational age estimation in the early first trimester of pregnancy: transabdominal versus transvaginal sonography.

A comparison is made between 290 patients examined using transabdominal sonography and 308 patients examined using transvaginal sonography. Patients with suboptimal menstrual histories and threatened miscarriages were excluded from these two groups of patients. The transabdominal and transvaginal sonography examinations were carried out while the patient's bladder was empty, so that there was no delay between the clinical and sonographic examinations. In this way there was no patient discomfort from a full bladder. In normal pregnancies after 42 days of amenorrhea, the percentage visualization rates of the chorionic sac, of the embryo with heart activity and of the yolk sac were measured. There were no significant differences between the two groups. The two techniques were able to provide a reliable diagnosis of miscarriage on embryos >or= 4 mm or with chorionic sacs >or= 10 mm mean diameter. However, before 42 days of gestation, transvaginal sonography was better than transabdominal sonography at diagnosing miscarriage. The percentage of anembryonic pregnancies was higher in the transabdominal sonography group (21%) than in the transvaginal sonography group (7%), despite similar gestational ages at the time of a positive diagnosis. Thus, a transabdominal scan can be used after 42 days and borderline cases can be referred for transvaginal sonography for confirmation.     

First-trimester, three-dimensional transvaginal ultrasound volumetry in normal pregnancies and spontaneous miscarriages.

OBJECTIVE: The aim of this study was to perform three-dimensional ultrasound volumetry of intrauterine contents in cases of normal and failed pregnancies and correlate these with conventional two-dimensional measurements. METHODS: This was a cross-sectional observational study. Three-dimensional volumetric data were collected from a total of 111 patients with first-trimester singleton pregnancies together with conventional two-dimensional measurements. A single investigator performed all ultrasound scans and volume measurements. RESULTS: Among 111 participants, 30 had an ongoing pregnancy and 81 had a miscarriage (anembryonic pregnancy 30, missed miscarriage 30, and incomplete miscarriage 21). There were no significant differences in age, parity, or gestational age between groups. A positive linear correlation was demonstrable between the crown-rump length and gestational sac volume in normal pregnancies (r = 0.962) and between gestational sac volume and gestational age, but the correlation was weaker in cases of missed miscarriage (r = 0.561). The volume of the retained products of conception as measured by three-dimensional ultrasound volumetry in cases of incomplete miscarriage also showed a strong linear correlation (r = 0.938) to their maximum anterior-posterior diameter. There was an exponential correlation between the mean gestational sac diameter and gestational sac volume and the crown-rump length and embryonic volume in cases of both normal and failed pregnancies. The mean gestational sac diameter:crown-rump length ratio (P = 0.008) and gestational sac volume:embryonic volume ratio (P = 0.023) in missed miscarriages were significantly higher than those in ongoing pregnancies. CONCLUSION: Three-dimensional ultrasound volumetry of intrauterine contents in normal and failed pregnancies correlates well with conventional two-dimensional measurements. Volumetric assessment does not seem to improve the diagnosis of miscarriage. However, its potential to predict pregnancies that will fail and determine the appropriate management regime for individual patients merits further research.     

Sonography of pregnancies with first-trimester bleeding and a small intrauterine gestational sac without a demonstrable embryo.

OBJECTIVE: This was a prospective observational cohort study to evaluate the outcome and prognostic criteria of pregnancies with first-trimester bleeding and a gestational sac 相似文献   

The significance of crown-rump length measurement for predicting adverse pregnancy outcome of threatened abortion.

OBJECTIVES: To determine if in women with threatened miscarriage the measurement of fetal crown-rump length (CRL) is a useful predictor of spontaneous miscarriage and small for gestational age (SGA) infants. METHODS: Fetal CRL was measured in 310 singleton pregnancies with live fetuses, presenting with threatened miscarriage before 13 weeks of gestation. The relationship between fetal CRL and pregnancy outcome was investigated. RESULTS: In fetuses with CRL < 18 mm there was a significant positive association between the deficit in CRL for gestation and the incidence of subsequent spontaneous miscarriage. In those cases with CRL deficit more than 2 standard deviations (SDs) the incidence of miscarriage was 13.7%, whereas if the CRL was between the mean and -2 SDs the incidence of miscarriage was 8.3%. In fetuses with CRL > or = 18 mm there was a significant positive association between the deficit in CRL for gestation and the incidence of SGA. In those cases with CRL deficit of more than 2 SD the incidence of SGA was 27.3%, whereas if the CRL was between the mean and -2 SDs the incidence of SGA was 18.9%. CONCLUSIONS: The findings of this study suggest that the measurement of fetal CRL may be a useful predictor of spontaneous miscarriage and SGA in pregnancies with threatened miscarriage.     

Sonographic appearance of the uterine cavity following administration of mifepristone and misoprostol for termination of pregnancy

PURPOSE: To describe the sonographic appearance of the uterine cavity in women after administration of mifepristone and misoprostol for termination of pregnancy. METHODS: Thirty-six women treated with mifepristone 600 mg followed by misoprostol 400 mug 2 days later for termination of pregnancy were the subjects of the study. Gestational age as calculated from the last menstrual period was < or =49 days. Pretreatment sonographic parameters, including gestational sac size and crown-rump length, were measured. The sonographic appearance of the uterine cavity was recorded and documented 6 hours (T-1) and 14 days (T-2) after administration of misoprostol. RESULTS: The mean menstrual age of the patients was 42 days (range 31-49 days). The mean gestational age according to crown-rump length was 43 days (range 40-48 days). Sonographic examination performed atT-1 revealed 23 patients (62.9%) with a well-defined echogenic mass located in the uterine cavity, 2 patients (5.5%) with an intrauterine sac containing a nonviable embryo, and 11 patients (30.5%) with an endometrium thickness of 7-14 mm with no evidence of intrauterine contents. Doppler flow signals were detected in 15 of the 23 patients (65.2%) with an echogenic intrauterine mass. Sonographic examination performed at T-2 revealed 19 patients (52.8%) with a persistent echogenic intrauterine mass; Doppler flow could be detected in 15 of these patients (78.9%). Dilatation and curettage was required in 2 patients (5.6%) due to failure of treatment; all others regained normal menses. CONCLUSIONS: An intrauterine echogenic mass with well-defined borders, with or without Doppler flow signals, can be detected 2 weeks after administration of mifepristone and misoprostol for termination of pregnancy. Because most of the women in our study regained normal menses without further surgical intervention, this finding could indicate remnants of trophoblastic tissue evacuated spontaneously from the uterine cavity. Therefore, dilatation and curettage should be avoided in these cases, unless clinical symptoms or signs necessitate surgical intervention.     

First trimester bleeding evaluation

First trimester bleeding is a common presentation in the emergency room. Ultrasound evaluation of patients with first trimester bleeding is the mainstay of the examination. The important causes of first trimester bleeding include spontaneous abortion, ectopic pregnancy, and gestational trophoblastic disease; 50% to 70% of spontaneous abortions are due to genetic abnormalities. In normal pregnancy, the serum beta hCG doubles or increases by at least 66% in 48 hours. The intrauterine GS should be visualized by TVUS with beta hCG levels between 1000 to 2000 mIU/mL IRP. Visualization of the yolk sac within the gestational sac is definitive evidence of intrauterine pregnancy. Embryonic cardiac activity can be identified with CRL of >5 mm. A GS with a mean sac diameter (MSD) of 8 mm or more without a yolk sac and a GS with an MSD of 16 mm or more without an embryo, are important predictors of a nonviable gestation. A GS with a mean sac diameter of 16 mm or more (TVUS) without an embryo is a sonographic sign of anembryonic gestation. A difference of <5 mm between the mean sac diameter and the CRL carries an 80% risk of spontaneous abortion. Approximately 20% of women with first trimester bleeding have a subchorionic hematoma. The presence of an extra ovarian adnexal mass is the most common sonographic finding in ectopic pregnancy. Other findings include the tubal ring sign and hemorrhage. About 26% of ectopic pregnancies have normal pelvic sonograms on TVUS. Complete hydatidiform mole presents with a complex intrauterine mass with multiple anechoic areas of varying sizes (Snowstorm appearance). Twenty-five percent to 65% of molar pregnancies have associated theca-leutin cysts. Arteriovenous malformation of the uterus is a rare but life-threatening cause of vaginal bleeding in the first trimester. The sonographic findings in a patient with first trimester bleeding should be correlated with serum beta hCG levels to arrive at an appropriate clinical diagnosis.     

Ultrasound measurements of fetal limb bones.

In order to establish the growth patterns of fetal limbs, measurements of femur, humerus, tibia, fibula, radius and ulna were made by ultrasound and related to gestational age. To this end, 2317 normal singleton pregnant women were studied cross-sectionally at 13-40 weeks of gestation. Patients were selected on the basis of a certain last menstrual period, history of regular cycles and at least one ultrasound scan before 16 weeks confirming gestational age. Linear growth of all limb measurements was observed between 13 and 28 weeks of gestation. From this gestational age onwards, a flattening of the growth curve was seen. A second-degree polynomial equation turned out to be the best model to describe this phenomenon. The measurements of all six fetal long bones showed a high correlation with menstrual age (r >or= 0.99). The femur displayed the largest mean weekly increments (2.8 mm per week from 13 to 28 weeks and 1.7 mm per week from 29 to 40 weeks of gestation) and the radius had the smallest (2.08 mm per week from 13 to 28 weeks and 1.25 mm per week from 29 to 40 weeks' gestation). Considering inter and intraoperator variations and the weekly increment of fetal long bone length, a correct evaluation of limb growth is possible for the femur every week before 28 weeks and every 2 weeks after 28 weeks. For the remaining limb bones, a correct evaluation is possible every 2 weeks at all gestational ages.     

Do early pregnancy ultrasound measurements correlate with fetal nuchal translucency at 11-14 weeks?

OBJECTIVE: To assess whether extremes in nuchal translucency (NT) thickness measurements at 11-14 weeks of gestation are preceded by departures from normal in early ultrasound biometry or embryonic heart rate in euploid fetuses. METHODS: This was a retrospective analysis of data from women with singleton pregnancies examined in early pregnancy between June 2002 and January 2003, who subsequently had a nuchal translucency (NT) scan. The early pregnancy scan was performed transvaginally, and the crown-rump length (CRL), mean gestational sac diameter (GS), mean yolk sac diameter (YS) and embryonic heart rate (HR) were measured where possible. At the second scan CRL and NT were measured. RESULTS: A total of 534 singleton pregnancies were included in the analysis. The mean maternal age was 30 (range, 14-45) years, and 59.4% of the patients were nulliparous. The mean CRL was 11.5 (range, 1.4-30.0) mm at the first scan and 62.8 (range, 42.0-88.0) mm at the second scan. GS, YS and HR measurements were obtained in 87.6%, 72.5% and 72.5% of cases, respectively. No statistically significant correlation was observed between NT and Z-scores of early pregnancy: GS (r = 0.013, P = 0.77), YS (r = 0.039, P = 0.44) or HR (r = 0.016, P = 0.76). GS, YS and HR were not significantly different in fetuses with NT measurements below the 10th percentile or above the 90th percentile (P = 0.24, 0.84 and 0.60, respectively). CONCLUSION: Ultrasound biometry and heart rate measured in early pregnancy are not related to nuchal translucency measurements at 11-14 weeks of gestation in chromosomally normal fetuses.     

Does gestational sac volume predict the outcome of missed miscarriage managed expectantly?

PURPOSE: The aim of this study was to investigate whether gestational sac volume (GSV) can predict the outcome of missed miscarriages that are managed expectantly. METHODS: This was a prospective observational study. Between February 1, 2000, and January 31, 2001, all patients with a confirmed first-trimester missed miscarriage who chose to undergo expectant management were recruited to participate. A single investigator performed all sonographic examinations and measurements. The main outcome measure was a complete spontaneous abortion within 4 weeks of the initial diagnosis. A complete miscarriage was defined as a maximum anteroposterior diameter of the endometrium of less than 15 mm on transvaginal sonography and no persistent heavy vaginal bleeding. The patients could opt to undergo surgery at any time, but those who had not expelled the products of conception within 4 weeks of the diagnosis were advised to have surgical uterine evacuation. RESULTS: In total, 90 patients were enrolled, and 86 patients completed the study. The mean GSV, as measured by 3-dimensional sonography, was 9.7 +/- 8.9 ml, and the mean sac diameter was 24.5 +/- 8.0 mm. A significant exponential correlation was found between the mean sac diameter and the GSV (r = 0.86; p < 0.0001). Forty-six (53.5%) of the 86 patients experienced a complete miscarriage within 4 weeks of the diagnosis (ie, expectant management was successful), but expectant management was unsuccessful in the remaining 40 (46.5%) patients (5 had an incomplete miscarriage, and 35 did not expel the products of conception). The GSV did not differ significantly between the "successful" and "unsuccessful" groups (p = 0.82). A logistic regression analysis showed no significant correlation between GSV and the outcome of missed miscarriages managed expectantly (p = 0.59). CONCLUSIONS: The GSV does not predict the outcome of expectant management of missed miscarriage within 4 weeks of the diagnosis.     

超声检查习惯性流产患者早孕期胎心率在妊娠结局中的预测价值

目的探讨超声检查习惯性流产（RSA）患者早孕期胎心率变化在妊娠结局预测中的作用。方法收集行超声检查的妊娠42~69 d的孕妇,其中,有RSA病史孕妇255例,无RSA病史孕妇201例。根据妊娠42~196 d（即6~28周）期间妊娠结局分为3组：RSA异常妊娠组（有RSA病史孕妇本次妊娠期间发生自然流产）;RSA正常妊娠组（有RSA病史孕妇本次妊娠至28周以上）;非RSA正常妊娠组（无RSA病史孕妇本次妊娠至28周以上）。孕妇经腹或经阴道超声测量孕囊大小及胚芽、胎儿头臀长,启用M取样并放大模式测量胎心率,连续测量3次,取均值,记录孕囊大小、头臀长及胎心率,追踪随访至妊娠28周,比较各组间资料。结果255例RSA孕妇中,83.0%的胚胎停育发生在55 d前,胎心率越低,胚胎停育发生率越高。超声检查与胚胎停育时间相隔越短,胎心率缓慢发生率越高。RSA正常妊娠组与非RSA正常妊娠组各孕龄平均胎心率的差异无统计学意义（P > 0.05）。RSA异常妊娠组与非RSA正常妊娠组孕49~62 d平均胎心率差异有统计学意义（P < 0.05）,孕42~48 d和孕63~69 d平均胎心率之间差异无统计学意义（P > 0.05）。用胎心率为检验变量,妊娠结局为金标准,预测胎心率诊断的价值,曲线面积为0.831,结果具有统计学意义（P < 0.05）。结论超声检查发现RSA患者早孕期胎心率缓慢对不良妊娠结局有一定的预测价值。     

一种简单的超声估计孕龄的方法

应用超声显像对588例6～41孕周的正常妊娠妇女进行了检查，测定了不同妊娠阶段的各种参数（包括妊娠囊最大直径及平均直径，胎儿双顶径、腹径及股骨长）。将这些参数与实际孕龄进行了相关和回归分析，建立了7个适合个不同孕周的孕龄估计公式，并将这些公式进行了简化。应用这些公式的简化式通过心算即可迅速得出结果，故其便于临床应用。经前瞻性验证表明，在6～12，12～20及20～41孕周，简化式估计孕龄的误差分别在±5天，±6天及±12天以内。     

Prediction of early pregnancy viability in the absence of an ultrasonically detectable embryo.

OBJECTIVE: To identify clinical, ultrasound and biochemical parameters that may allow prediction of pregnancy viability in women without a detectable embryo on ultrasound examination. METHODS: This was a prospective observational study of pregnant women with an ultrasound finding of a gestational sac measuring < 20 mm mean diameter without a visible embryo. Women's age, menstrual dates, clinical symptoms (pain and bleeding), mean gestational sac diameter and measurements of serum beta-human chorionic gonadotropin and progesterone were recorded in all cases. All women were managed expectantly until the pregnancy viability was established conclusively based on clinical and ultrasound findings. All parameters were tested by univariate analysis and then analyzed in a stepwise procedure to form a logistic regression model for predicting pregnancy viability. RESULTS: One hundred and eighteen (59%) women had a normal intrauterine pregnancy and 82 (41%) had a miscarriage. Stepwise analysis showed that three diagnostic parameters (maternal age, gestational sac diameter and serum progesterone) contributed significantly to the predictive power of the logistic model. With this model, at a cut-off value of 10% probability, the diagnosis of viable pregnancy was made with a sensitivity of 99.2% (95% CI, 95.8-99.97) and specificity of 70.7% (95% CI, 61.3-78.9). CONCLUSION: The use of a logistic regression model allows prediction of pregnancy viability when an embryo cannot be visualized on ultrasound scan.     

Normal Intrauterine Pregnancy Is Unlikely in Emergency Department Patients with Either Menstrual Days >38 Days or β-hCG >3,000 mlU/mL, but without a Gestational Sac on Ultrasonography

Objective : To determine whether the absence of a gestational sac on transvaginal ultrasonography in patients with a quantitative beta-human chorionic gonadotropin (β-hCG) >3,000 mIU/mL and/or menstrual days >38 excludes the diagnosis of a normal intrauterine pregnancy (IUP).
Methods : A retrospective analysis was performed of ED patients evaluated from August 1991 to December 1994 at an urban teaching hospital. Patients presented with abdominal pain and/or vaginal bleeding and had a positive serum β-hCG test. Patients who had transvaginal ultrasonographies performed during the ED visit that were read as indeterminate were reviewed. Menstrual days were determined by subtracting the date of the last normal menstrual period (LMP) from the ED visit date. ED β-hCGs were quantified. Patients were excluded if the LMP or quantitative β-hCG result was not available or if the final diagnosis could not be definitively determined.
Results : 248 patients met eligibility criteria; of these, 54 were excluded. Therefore, 194 patients were enrolled. Menstrual days ranged from 5 to 151, with a median of 54 days. Of 143 patients with menstrual days >38 and no gestational sac by ultrasonography, only 4 (2.8%) had a final diagnosis of normal IUP. The menstrual days for the 4 normal IUPs were 39, 41, 42, and 59 days. β-hCGs ranged from 19 to 151,926 mIU/mL, with a median of 2,410 mIU/mL. None of the 74 patients with a β-hCG >3,000 mIU/mL and no gestational sac by ultrasonography had a final diagnosis of normal IUP.
Conclusion : In patients with either a β-hCG >3,000 mIU/mL or menstrual days >38 and no gestational sac by transvaginal ultrasonography, the likelihood of a normal IUP is low.     

Detection of fetal cardiac activity between 41 and 43 days of gestation.

Using a high-resolution real-time arc sector scanner, fetal cardiac activity was detected in ten normal intrauterine pregnancies, including one triplet gestation, between 41 and 43 days of gestation. Fetal heart rates ranged from 96 to 120 beats/min (mean 110) and were detected contiguous with the yolk sac as a tiny blinking, flashing, and/or rocking echo with a regular rhythm. The mean gestational sac fluid diameters ranged from 8 to 16 mm and the crown-rump lengths, when measurable, were less than 4 mm. The demonstration of early fetal cardiac activity in utero reduces parental anxiety and indicates a favorable prognosis in patients with threatened abortion, and virtually excludes the diagnosis of ectopic pregnancy.     

Ultrasonic planimetry of the gestation sac as a biometric method in early pregnancy.

A new method for determining the area of the gestation sac by thread planimetry is described. Mean weekly values with two standard deviations were determined on a series of 237 measurements of gestation sac area, age five to 11 weeks, in normal pregnancies. The gestation sac area grows curvilinearly from 1.85 cm2 at five weeks to 15 cm2 at 11 weeks. The mean diameter was calculated from the gestation sac area by using an adequate approximation of the irregular gestation sac shape to a circle of the same area. The dependence of the mean gestation sac diameter on gestation age is defined by the regression equation y = 0.46x - 0.95 and the correlation factor r = 0.92. Practical applications of gestation sac planimetry include the determination of gestation age in early pregnancy, and the follow-up of growth or determination of delayed growth in disturbed or failed early pregnancy.     

Endovaginal ultrasonographic measurement of early embryonic size as a means of assessing gestational age.

Crown-rump length has consistently been found to be the most accurate method of determining gestational age in the first trimester. The original regression curve established by Robinson in 1973 with static arm scanners remains the one most widely employed. New endovaginal ultrasonographic probes afford a degree of detail that allows embryonic structures to be seen as soon as they are distinct from the yolk sac. Previously, measurements of very early embryonic structures have mistakenly been labeled crown-rump lengths. There has been widespread use of nomograms constructed from regression curves, where the bulk of the data were derived from small fetuses and then such curves extrapolated back to embryos of very small size. The purpose of this study was to establish a nomogram for gestational age assessment by measuring early embryos prior to the development of a "crown" or "rump." This present study consisted of 143 patients. To be included they had to have had no history of any prior bleeding, and all were delivered of singleton infants within 2 weeks of their estimated delivery date by last menstrual period. All had a single early embryonic size measurement between 1 and 25 mm using high-frequency endovaginal probes. Regression analysis revealed a linear equation of Gestational age (days) = early embryonic size (mm) + 42 with a correlation coefficient r = 0.87; 95% confidence limit = +/- 3 days. We conclude that using high-frequency vaginal ultrasonographic probes and having a better understanding of embryonic anatomic stages allow for the construction of a nomogram of gestational age derived from measurements of early embryonic size prior to development of a crown-rump length.     

How to identify twins at low risk of spontaneous preterm delivery.

OBJECTIVE: The aim of this study was to evaluate transvaginal sonographic assessment of cervical length at 23 weeks as a screening test for spontaneous preterm delivery in order to define a cut-off value that could be used to select twin pregnancies at low risk of spontaneous preterm delivery. METHODS: In a prospective multicenter study of 383 twin pregnancies included before 14 + 6 weeks a cervical scan with measurement of the cervical length was performed at 23 weeks' gestation. The results were blinded for the clinicians if the cervical length was > or = 15 mm. The rates of spontaneous delivery at different cut-off levels of cervical length were determined. RESULTS: Eighty-nine percent of the twins had dichorionic placentation and 58% were conceived after assisted reproduction. The rate of spontaneous preterm delivery was 2.3% (1.5% for dichorionic (DC) and 9.1% for (MC) monochorionic twins) before 28 weeks and 18.5% (17.1% for DC and 29.5% for MC twins) before 35 weeks. The screen-positive rate was 5% for a cervical length < or = 20, 7-8% at < or = 25, 16-17% at < or = 30 and 34-48% at < or = 35 mm depending on chorionicity. The false-negative rate (1 - negative predictive value) ranged from 1.2% at 28 weeks to 18.6% at 35 weeks for all twins. Receiver-operating characteristics curves showed that the sensitivity increased with declining gestational age with cut-off levels of highest accuracy at 21 mm for 28 weeks and 29 mm for 33 weeks. CONCLUSIONS: Cervical length measurement at 23 weeks of gestation is a good screening test for predicting twins at low risk of preterm and very preterm delivery, especially in DC twins. The present results suggest that a cut-off of 25 mm should be recommended.     

Crown-rump lengths in missed miscarriages and trisomy 21.

OBJECTIVES: To compare crown-rump lengths with karyotypes of missed miscarried fetuses and to determine a relationship between crown-rump length and trisomy 21. STUDY DESIGN: Chorionic villus sampling was performed on 129 consecutive missed miscarriages between 10 and 12 weeks by last menstrual period in patients >or= 35 years of age. Crown-rump length was correlated with the karyotype. Statistical analysis was performed using Student's t-test. RESULTS: Twenty-one of 129 missed miscarriages involved fetuses affected by trisomy 21. The crown-rump length was < 22 mm in 77% of missed miscarriages. Using a crown-rump length of >or= 22 mm for the prediction of trisomy 21 had a sensitivity of 86%, specificity of 89%, positive predictive value of 60% and negative predictive value of 97%. At 10-12 weeks, the crown-rump lengths of missed miscarried fetuses with trisomy 21 was significantly larger (P or= 35 years of age, with a missed miscarriage, in whom pregnancies reached >or= 10 weeks from the last menstrual period, a fetal crown-rump length of >or= 22 mm has a high probability that the etiology of the loss will be secondary to trisomy 21.     

Early sonographic evaluation for fetal growth delay and congenital malformations in pregnancies complicated by insulin-requiring diabetes. National Institute of Child Health and Human Development Diabetes in Early Pregnancy Study.

OBJECTIVE--It has been reported that early fetal growth retardation may be a useful marker for congenital malformations in diabetic pregnancies. To test this hypothesis, diabetic and nondiabetic women were sonographically evaluated during the first trimester. RESEARCH DESIGN AND METHODS--Fetal crown-rump lengths were measured sonographically at least once during the first 15 wk of pregnancy in 329 nondiabetic and 312 diabetic women. Of these, 289 nondiabetic and 269 diabetic women had sonograms before 10 wk of gestation and 283 nondiabetic and 269 diabetic women had sonograms between 10 and 15 wk of gestation. Early fetal growth delay was defined as a sonographic gestational age of greater than or equal to 6 days less than menstrual gestational age. RESULTS--The mean crown-rump lengths at 8 wk were 17.9 +/- 4.6 mm in the diabetic and 18.7 +/- 4.9 mm in the nondiabetic groups (P = 0.13). At 12 wk, the mean fetal crown-rump length was 58.5 +/- 8.8 mm for diabetic subjects and 60.6 +/- 8.7 mm for nondiabetic subjects (P = 0.04). Between 5 and 9 wk, 28 of 289 (9.7%) fetuses of nondiabetic subjects, 34 of 259 (13.1%) normal fetuses of diabetic subjects, and 2 of 10 (20%) malformed fetuses of diabetic subjects demonstrated growth delay (P = 0.31, normal vs. malformed diabetic). Between 10 and 15 wk of gestation, 28 of 283 (9.9%) fetuses of nondiabetic subjects, 32 of 256 (12.5%) normal fetuses of diabetic subjects, and 4 of 13 (30.8%) malformed fetuses of diabetic subjects demonstrated growth delay (P = 0.06, normal vs. malformed diabetic). Early fetal growth delay did not predict a reduced birth weight at term. CONCLUSIONS--Among insulin-dependent diabetic subjects who were moderately well controlled at conception, statistically significant but mild early fetal growth delay was present but did not appear to be useful clinically in predicting congenital malformations. Recommendations that growth delay demonstrated on early ultrasound be used as a predictor of congenital malformation require careful reexamination.     

Ultrasound dating at 12-14 weeks of gestation. A prospective cross-validation of established dating formulae in in-vitro fertilized pregnancies.

OBJECTIVES: To determine the accuracy of established ultrasound dating formulae when used at 12-14 weeks of gestation. METHODS: One-hundred and sixty-seven singleton pregnancies conceived after in-vitro fertilization (IVF) underwent a dating scan at 12-14 weeks of gestation. Gestational age at the dating scan was calculated by adding 14 days to the number of days between the date of oocyte retrieval and the date of the ultrasound scan. Gestational age according to oocyte retrieval was regarded as the true gestational age. True gestational age was compared to gestational age calculated on the basis of 21 dating formulae based on fetal crown-rump length (CRL) measurements and to three dating formulae based on fetal biparietal diameter (BPD) measurements. In a previous study the three BPD formulae tested here had been shown to be superior to four other BPD formulae when used at 12-14 weeks of gestation. The mean of the differences between estimated and true gestational age and their standard deviation (SD) were calculated for each formula. The SD of the differences was assumed to reflect random measurement error. Systematic measurement error was assumed to exist if zero lay outside the mean difference+/-2SE (SE: standard error of the mean). RESULTS: The three best CRL formulae were associated with mean (non-systematic) measurement errors of -0.0, -0.1 and -0.3 days, and the SD of the measurement errors of these formulae varied from 2.37 to 2.45. All but two of the remaining CRL formulae were associated with systematic over- or under-estimation of gestational age, and the SDs of their measurement error varied between 2.25 and 4.86 days. Dating formulae using BPD systematically underestimated gestational age by -0.4 to -0.7 days, and the SDs of their measurement errors varied from 1.86 to 2.09. CONCLUSIONS: We have identified three BPD formulae that are suitable for dating at 12-14 weeks of gestation. They are superior to all 21 CRL formulae tested here, because their random measurement errors were much smaller than those of the three best CRL formulae. The small systematic negative measurement errors associated with the BPD formulae are likely to be clinically unimportant.