Vasiliki Michalitsi

National and Kapodistrian University of Athens

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Athena P. Souka

National and Kapodistrian University of Athens

Ioannis Papastefanou

King's College London

Dimitrios Kassanos

National and Kapodistrian University of Athens

Athanasios Pilalis

LETO Maternity Hospital

ΠΠ

Περικλής Παναγόπουλος

University General Hospital Attikon

George K. Papadopoulos

Agricultural University of Athens

D Kassanos

National and Kapodistrian University of Athens

Charalambos Chrelias

National and Kapodistrian University of Athens

H. Skentou

University of Thessaly

Konstantinos Salambasis

National and Kapodistrian University of Athens

Cooperative Institutions

National and Kapodistrian University of Athens

University General Hospital Attikon

LETO Maternity Hospital

Aretaeio Hospital

King's College Hospital

Harris Birthright Research Centre for Fetal Medicine

Tzaneion General Hospital

Alexandra Hospital

Athens State University

University of Thessaly

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First trimester prediction of small‐ and large‐for‐gestation neonates by an integrated model incorporating ultrasound parameters, biochemical indices and maternal characteristics

Acta Obstetricia Et Gynecologica Scandinavica (2011)

Ioannis Papastefanou Athena P. Souka Athanasios Pilalis Makarios Eleftheriades Vasiliki Michalitsi

Abstract Objective. To identify maternal/pregnancy characteristics, first trimester ultrasound parameters and biochemical indices which are significant independent predictors of small‐for‐gestational age (SGA) and large‐for‐gestational age (LGA) neonates. Design. Retrospective cross‐sectional study. Setting. Two fetal Medicine Units. Population. 4 702 singleton pregnancies presenting for screening for chromosomal abnormalities by nuchal translucency and maternal serum biochemistry at 11–14 weeks. Methods. Reference ranges for birthweight applied to our population were constructed by the Royston and Wright method. Multiple logistic regression was applied to develop first trimester prediction models for SGA and LGA. Main outcome measures. Birth of SGA or LGA neonate. Results. Maternal height, parity, smoking, assisted conception, delta crown–rump length, delta nuchal translucency, free beta human chorionic gonadotrophin and pregnancy‐associated plasma protein‐A were significant independent predictors of SGA. Maternal weight and height, smoking, delta crown–rump length and delta nuchal translucency were significant independent predictors of LGA. Models for SGA (AUC=0.7296, CI: 0.69–0.76, p <0.0001) and LGA (AUC=0.6901, CI: 0.65–0.72, p <0.0001) were derived, applicable to routine obstetric population at low risk for these conditions. For 20% screen positive rate the modeling achieves sensitivities of about 55% for SGA and 48% for LGA neonates. Conclusion. Prediction for birthweight deviations is feasible using data available at the routine 11–14 weeks’ examination. Delta CRL and delta nuchal translucency were significant independent predictors for both SGA and LGA.

Crown-rump length

10.1111/j.1600-0412.2011.01271.x

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Citations (45)

Cervical Length Changes From the First to Second Trimester of Pregnancy, and Prediction of Preterm Birth by First‐Trimester Sonographic Cervical Measurement

Journal of Ultrasound in Medicine (2011)

Athena P. Souka Ioannis Papastefanou Vasiliki Michalitsi Konstantinos Salambasis Charalambos Chrelias

Objectives The purpose of this study was to examine the evolution of cervical length from the first to second trimester of pregnancy and the value of first‐trimester cervical measurement in the prediction of preterm delivery. Methods We conducted a longitudinal prospective study. Cervical length was measured by transvaginal sonography at 11 to 14 weeks (Cx1), 16 to 19 weeks (Cx2), and 20 to 24 weeks (Cx3). Results Eight hundred singleton pregnancies were studied. The median cervical lengths were 33 mm for Cx1 and 31 mm for Cx2 and Cx3. Significant independent predictors for cervical length were maternal weight, height, and history of cervical surgery for Cx1, maternal height, history of cervical surgery, and history of preterm delivery for Cx2, and history of cervical surgery, history of first‐trimester miscarriage, and history of spontaneous preterm delivery for Cx3. Mean cervical length shortening was 2.36 mm between Cx1 and Cx3. In the subgroups of women with previous cervical surgery and history of previous preterm birth, cervical shortening was significantly more prominent. The median Cx1 was significantly shorter in the women who subsequently delivered preterm; Cx1 predicted preterm delivery before 34 weeks (odds ratio, 0.746; 95% confidence interval, 0.649–0.869) and preterm delivery before 32 weeks (odds ratio, 0.734; 95% confidence interval, 0.637–0.912). Conclusions Cervical length in the first trimester depends on maternal characteristics and a history of cervical surgery. The cervix exhibits minimal changes from 11 to 24 weeks for most women, although the shortening is more prominent in women with a history of cervical surgery or preterm delivery. First‐trimester cervical length measurement can predict preterm delivery.

10.7863/jum.2011.30.7.997

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Third trimester ultrasound for the prediction of the large for gestational age fetus in low‐risk population and evaluation of contingency strategies

Prenatal Diagnosis (2012)

Athanasios Pilalis Athena P. Souka Ioannis Papastefanou Vasiliki Michalitsi Περικλής Παναγόπουλος

ABSTRACT Objective Evaluation of the effectiveness of third trimester fetal biometry and Doppler studies in predicting the birth of a large for gestational age neonate (LGA ≥ 95 th centile). Assessment of the value of integrated models (combining maternal characteristics, first trimester parameters, third trimester fetal biometry) and the usefulness of contingency strategies. Method Observational cross‐sectional study on 2308 uncomplicated singleton pregnancies examined at 11 to 14 weeks and at 30 to 34 weeks. Results Ultrasound estimated fetal weight (EFW, area under the curve (AUC) = 0.83) was the best single predictor of LGA. Maternal weight, delta nuchal translucency and EFW were independent predictors for the integrated model, but the latter was not statistically better (AUC = 0.84) than using EFW alone. The detection rates for LGA were 72.5% and 73.7% for a 25% screen positive rate, by EFW and the third trimester integrated model respectively. A contingency strategy of rescanning 50% of the population in the third trimester according to the risk estimation by a first trimester prediction model results in detection rate of 64.7% for LGA for the same 25% screen positive rate (AUC = 0.78). Conclusions Third trimester ultrasound is an effective screening modality for identifying fetal macrosomia. A contingency strategy utilizing first trimester parameters can reduce the need for unnecessary examinations. © 2012 John Wiley & Sons, Ltd.

10.1002/pd.3918

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Prenatal diagnosis of fetal hemivertebra in the first trimester

Case Reports in Perinatal Medicine (2019)

Christos Parthenis Vasiliki Michalitsi C. Chlapoutaki Athena P. Souka

Abstract Hemivertebra is a congenital spinal abnormality. The condition may affect one or multiple vertebrae. Hemivertebra occurs because of malformations or absence of the ossification centers. Most cases reported in the literature are diagnosed in the second trimester, usually after 22 weeks. It is very unusual and difficult for the hemivertebra to be detected at the first trimester.

Abnormality

10.1515/crpm-2018-0050

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Attitudes of pregnant women regarding termination of pregnancy for fetal abnormality

Prenatal Diagnosis (2010)

Athena P. Souka Vasiliki Michalitsi H. Skentou H. Euripioti George K. Papadopoulos

Abstract Objective To study the attitudes of pregnant women towards termination of pregnancy for fetal abnormality. Materials and methods A questionnaire was completed by all pregnant women attending routine ultrasound scan. They were asked whether they would opt for termination of the pregnancy in case the fetus was diagnosed with one of the following abnormalities: lethal anomaly, anomaly causing developmental delay, anomaly causing physical handicap, anomaly causing disfigurement and severe anomaly diagnosed after 24 weeks of pregnancy. Logistic regression analysis was used to examine the effect of a variety of demographic and socio‐economic characteristics in their choices. Results A total of 533 women completed the questionnaire out of which 447 (86%) would terminate the pregnancy in case of lethal fetal anomaly. The corresponding figures for anomaly causing developmental delay, anomaly causing physical handicap and anomaly causing disfigurement were 396 (77.8%), 332 (65.9%) and 228 (45.2%). A total of 313 (64.7%) would request late termination owing to severe anomaly. The only two statistically significant factors that influenced the maternal decision on pregnancy termination were religious beliefs and the frequency of practicing religious duties ( p < 0.001). Conclusion The majority of pregnant women would terminate pregnancy for lethal fetal anomaly and for an anomaly causing mental or physical handicap, even in late pregnancy. Copyright © 2010 John Wiley & Sons, Ltd.

Disfigurement

Abnormality

Anomaly (physics)

10.1002/pd.2600

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Performance of third‐trimester ultrasound for prediction of small‐for‐gestational‐age neonates and evaluation of contingency screening policies

Ultrasound in Obstetrics and Gynecology (2011)

Athena P. Souka Ioannis Papastefanou Athanasios Pilalis Vasiliki Michalitsi Dimitrios Kassanos

Abstract Objectives To assess the performance of third‐trimester fetal biometry and fetal Doppler studies for the prediction of small‐for‐gestational‐age (SGA) neonates, and to explore contingency strategies using a first‐trimester prediction model based on maternal and fetal parameters and third‐trimester ultrasound. Methods This was an observational cross‐sectional study of uncomplicated singleton pregnancies. Risk assessment for chromosomal abnormality was carried out in 4702 pregnancies using a combination of ultrasound markers (fetal nuchal translucency thickness (NT) and nasal bone assessment) and biochemistry (free beta‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A)) at 11 to 13 + 6 weeks. Maternal demographic characteristics and method of conception were recorded. Third‐trimester (30–34 weeks) fetal biometry (biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL)) and umbilical artery (UA) and middle cerebral artery Doppler studies were performed routinely in a subgroup ( n = 2310). Reference ranges for birth weight were constructed using the cohort of 4702 women, and neonates were classified as small (SGA, ≤ 5th centile) or appropriate (AGA) for gestational age. First‐trimester, third‐trimester and integrated first‐ and third‐trimester prediction models for SGA were constructed using regression analysis and three different contingency strategies of rescanning in the third trimester were investigated. Results According to the areas under the receiver–operating characteristics curves (AUCs), AC (AUC = 0.85) and ultrasound‐estimated fetal weight (EFW, AUC = 0.87) were equally good predictors of SGA. The model was marginally improved by the addition of UA Doppler, smoking status and first‐trimester indices (free β‐hCG and PAPP‐A multiples of the median) (combined model, AUC = 0.88), but the difference was not statistically significant. A contingency strategy of rescanning 50% of the population in the third trimester according to the risk estimated by a first‐trimester prediction model yielded a detection rate of 79% for a 25% screen‐positive rate. Conclusion Third‐trimester ultrasound is effective in screening for SGA in uncomplicated pregnancies. The use of a contingency screening policy can reduce the need for unnecessary examinations. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

Umbilical artery

10.1002/uog.10078

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Specific formulas improve the estimation of fetal weight by ultrasound scan

The Journal of Maternal-Fetal & Neonatal Medicine (2013)

Athena P. Souka Ioannis Papastefanou Vasiliki Michalitsi Athanasios Pilalis Dimitrios Kassanos

To develop and evaluate local, sex specific, small for gestational age (SGA) specific, large for gestational age (LGA) specific and combined (biometry, sex and Doppler indices) formulas for ultrasound estimated fetal weight (EFW).Low-risk singleton pregnancies that delivered within 7 days from ultrasound examination were assessed. A formula-generating group (1407 pregnancies) and a validation group (469 pregnancies) were created. Fractional regression analysis was used to develop the formulas. Systematic error, random error, fraction within the 10% of actual birth weight and Bland-Altman analysis were used.The local formula and the Hadlock formula with local co-efficients performed better than the Hadlock formula. The SGA-specific formula, the LGA-specific formula and the combined formula had the lower systematic error (MSE: +0.0022291, -0.4226888, +0.8386222, respectively) and the narrower 95% LOA (-292.8 to +292.23, -485.6 to +461.5, -425.7 to +450.46, respectively). The SGA- and the LGA-specific formulas had higher fraction within the 10% of actual birth weight (81.5% and 84%, respectively).Local formulas improve the EFW calculation. The combined formula can further optimize the accuracy and precision. Application of specific formulas for the small and the large fetus had the most pronounced effect in improving fetal weight estimation.

Fetal weight

Singleton

Fraction (chemistry)

Weight estimation

10.3109/14767058.2013.837877

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Performance of the ultrasound examination in the early and late third trimester for the prediction of birth weight deviations

Prenatal Diagnosis (2013)

Athena P. Souka Ioannis Papastefanou Athanasios Pilalis Vasiliki Michalitsi Περικλής Παναγόπουλος

ABSTRACT Objectives This study aimed to define the optimal gestational age in the third trimester, early (30–33 weeks + 6 days) versus late (34–37 weeks), for performing an ultrasound examination for fetal biometry to predict birth weight deviations: small for gestational age (SGA ≤ 5th centile) and large for gestational age (LGA ≥ 95th centile) neonates. Methods We used an observational cross‐sectional study in uncomplicated singleton pregnancies that had a third trimester ultrasound for fetal biometry and umbilical and middle cerebral fetal Doppler studies. Estimated fetal weight and fetal Doppler parameters were the examined variables for the prediction of SGA and LGA. Results Three thousand six hundred ninety women had an early examination, and 2288 women had a late one. For a screen‐positive rate of 10%, estimated fetal weight achieved 58% and 53.4% sensitivity for the prediction of SGA [area under the curve ( AUC ) = 0.8578, p < 0.001] and LGA ( AUC = 0.8547, p < 0.001), respectively, by the early examination. Accordingly, the sensitivities significantly increased to 75.2% and 63.2% for the prediction of SGA ( AUC = 0.9074, p < 0.001) and LGA ( AUC = 0.8782, p < 0.001), respectively, by the late examination. The inclusion of the Doppler indices did not improve the predictive models. Conclusions A late third trimester ultrasound was superior in the prediction of SGA and LGA, and this improvement was more pronounced for the prediction of SGA. © 2013 John Wiley & Sons, Ltd.

Third trimester

10.1002/pd.4161

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A predictive model of short cervix at 20–24 weeks using first‐trimester cervical length measurement and maternal history

Prenatal Diagnosis (2011)

Athena P. Souka Ioannis Papastefanou Vasiliki Michalitsi George K. Papadopoulos D Kassanos

Abstract Objectives To develop a model for the prediction of short cervix ( ≤ 15 mm) at 20–24 weeks by combining maternal history and transvaginal ultrasonographic measurement of cervical length at 11–14 weeks. To explore the value of an additional ultrasound examination of the cervix at about 17 weeks. Methods Longitudinal prospective study in 800 unselected pregnant women presenting for first‐trimester ultrasound assessment by nuchal translucency and serum biochemistry. Cervical length was evaluated transvaginally between 11 weeks and 13 weeks and 6 days (cx1), at 16–19 weeks (cx2) and 20–24 weeks (cx3). Backward multiple logistic regression analysis with cx3 ≤ 15 mm as the dependent variable was used to identify the predictors of a short cervix at 20–24 weeks. Results Cx1 and history of preterm delivery were significant independent contributors of a short cervix at 20–24 weeks [area under the curve (AUC 0.808, p < 0.001, Model) 1]. Furthermore, the cx1/cx2 ratio was a significant independent predictor of a short cervix at 20–24 weeks (odds ratio = 58.325 p = 0.012). The addition of the cx1/cx2 ratio improved the model (AUC = 0.878, p < 0.001, Model 2). Conclusions A short cervix at 20–24 weeks can be predicted at the 11–14 weeks scan. The addition of a cervical measurement at about 17 weeks can improve the prediction model. Copyright © 2011 John Wiley & Sons, Ltd.

10.1002/pd.2683

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Citations (24)