Obstetrics and GynecologyPrenatal screening, fetometry, gynecological ultrasound according to international standards.
Vasa previa is the presentation of umbilical cord vessels over the internal cervical os. Prenatal ultrasound diagnosis relies on transvaginal scanning with color Doppler and targeted …
Read →Ultrasound diagnosis of PAS relies on standardized findings (Alfirevic et al., Collins et al.): abnormal placental lacunae, myometrial thinning, loss of the clear zone, bladder wall …
Read →Antenatal diagnosis of TAPS is established by Doppler measurement of MCA-PSV: according to the Delphi consensus, thresholds of MCA-PSV > 1.5 MoM in the donor and …
Read →Selective fetal growth restriction (sFGR) in monochorionic twin pregnancy is classified according to the Doppler spectrum pattern in the umbilical artery of the smaller twin (Gratacós, …
Read →Screening for open spina bifida on ultrasound at 11–13/11–14 weeks is based on assessment of intracranial translucency (IT) and the posterior brain region in the mid-sagittal …
Read →Scar niche (isthmocele) is assessed by ultrasound with mandatory measurement of residual myometrium — the thickness of tissue between the defect and bladder wall. Available fragments …
Read →Retained products of conception (RPOC) are identified on ultrasound as an intra-cavitary mass within the uterus following delivery or abortion; the combination of grayscale imaging and …
Read →Decidualized endometrioma is an important diagnostic pitfall during pregnancy: under the influence of gestational hormones, papillary projections with vascularization develop within the endometrioma, mimicking malignancy and …
Read →According to the IDEA protocol, sliding sign is a dynamic transvaginal technique for assessing the mobility of the posterior uterine wall/cervix relative to the rectum. A …
Read →According to IOTA, endometrioma is a uni- or weakly multilocular cyst with homogeneous low-level echosignals ('ground-glass'), smooth wall, and no vascularized solid tissue on Doppler. Hemorrhagic …
Read →Hydrosalpinx on ultrasound is visualized as an elongated fluid-filled tubular structure with incomplete septa. Characteristic findings include the 'cogwheel sign' (small bulges <3 mm along the …
Read →For standardized ultrasound description of uterine fibroids, the FIGO classification (2011, PALM-COEIN) is used for node localization (types 0–8) and MUSA terminology (consensus, 2015) for describing …
Read →Endometrial polyp is often visualized as a localized echogenic or mixed-echogenicity lesion within the uterine cavity, sometimes with a feeding vessel. Submucosal leiomyoma, conversely, deforms the …
Read →Abdominal wall defects (AWD) complicate approximately 6–7 cases per 10,000 deliveries in the USA and are most commonly represented by gastroschisis or omphalocele (Ultrasound Obstet Gynecol, …
Read →Non-immune fetal hydrops (NIHF) is diagnosed on ultrasound when fluid accumulates in two or more fetal serous cavities, including skin edema, ascites, pleural and/or pericardial effusion. …
Read →For standardized assessment of fetal urinary tract dilation, a multidisciplinary UTD consensus (Nguyen HT et al., 2014) is applied, referenced in current ISUOG, ACR–ACOG–AIUM–SMFM–SRU guidelines. It …
Read →According to the updated ISUOG 2023 guidelines for ultrasound performance at 11–14 weeks, first trimester screening allows assessment of basic fetal anatomy, determination of gestational age …
Read →The diagnosis of cesarean scar pregnancy (CSP) is justified when four ultrasound criteria (ISUOG, 2024) are fulfilled: empty uterine cavity and cervical canal without gestational sac; …
Read →MCA-PSV is the primary non-invasive method for detecting fetal anemia: according to SMFM, it has replaced routine assessment of amniotic fluid bilirubin. A threshold value of …
Read →First trimester preeclampsia screening using the Fetal Medicine Foundation (FMF) algorithm is performed at 11–13 weeks and combines maternal factors, mean arterial pressure (MAP), uterine artery …
Read →Fetal ventriculomegaly is diagnosed when the transverse measurement of the lateral ventricle atrium is >10 mm. Measurement is performed at the level of the glomus of …
Read →Differential ultrasound diagnosis of cystic anomalies of the posterior fossa (Dandywalker malformation, Blake's pouch cyst) relies on assessment of the cerebellar vermis, position of the choroid …
Read →The 'lemon sign' and 'banana sign' are intracranial ultrasound markers of open spina bifida assessed during routine screening. Their diagnostic value was demonstrated in the landmark …
Read →Soft markers of aneuploidy are ultrasound findings in the second trimester associated with chromosomal pathology. In the era of NIPT, their independent role is being reconsidered: …
Read →When assessing placental location, the shortest distance from the lower edge of the placenta to the internal cervical os is measured. According to ISUOG (2024), at …
Read →TAPS in monochorionic twin pregnancy is diagnosed when donor MCA-PSV >1.5 MoM and recipient MCA-PSV <1.0 MoM, or when the inter-twin difference (delta) >0.5 MoM. Doppler …
Read →The Gratacos classification divides selective FGR in monochorionic twin pregnancy into three types based on umbilical artery blood flow patterns in the smaller fetus. It was …
Read →According to ISUOG recommendations (2024), amniotic fluid volume is assessed subjectively ('normal'/'decreased'/'increased') or semi-quantitatively. AFI is preferable for polyhydramnios assessment, whereas maximum vertical pocket (DVP/SDP) is …
Read →In dichorionic diamniotic (DCDA) twin pregnancy, the fetuses are separated by a thick layer of fused chorionic membranes with two thin amniotic layers—forming a "complete lambda" …
Read →Twin-to-twin transfusion syndrome (TTTS) in monochorionic pregnancy is staged according to the Quintero system based on ultrasound findings: diagnosis is established when the maximum vertical pocket …
Read →Key sonographic markers of the placenta accreta spectrum (PAS) include low anterior placenta or placenta previa overlying a cesarean scar, multiple irregular placental lacunae with architectural …
Read →Vasa previa is diagnosed on transvaginal ultrasound with color Doppler imaging: unprotected fetal vessels crossing the membranes over the internal cervical os or within <20 mm …
Read →According to the ISUOG/IDEA 2024 consensus, expert transvaginal ultrasound (TV-US) is the first-line method for non-invasive diagnosis and preoperative mapping of pelvic deep endometriosis. MRI is …
Read →The IOTA 2026 update is the first major revision of terms for describing adnexal masses since 2000. In the practical protocol, key elements remain the measurement …
Read →In O-RADS US v2022, the risk of malignancy is coded as follows: O-RADS 2 — less than 1%, O-RADS 3 — from 1% to less than …
Read →According to IETA/ISUOG 2026, the endometrium is measured in the mid-sagittal plane as the maximum anteroposterior dimension of the 'double layer' in mm; when intracavitary fluid …
Read →The revised MUSA 2022 definitions divide ultrasound signs of adenomyosis into direct and indirect. The key diagnostic rule: at least one direct sign is required for …
Read →The IDEA 2025 addendum standardizes for the first time the transvaginal sonographic assessment of superficial, or peritoneal, endometriosis; the document is published in Ultrasound in Obstetrics …
Read →According to ISUOG 2025, chorionicity and amnionicity should be established in the first trimester, optimally during the 11–13+6 week scan. Uncomplicated monochorionic twins are monitored with …
Read →According to ISUOG 2024, third-trimester ultrasound is performed from 28+0 weeks until delivery: the mandatory minimum includes fetal presentation, biometry with EFW calculation, placental localization, assessment …
Read →According to AIUM 2024, the first trimester ends at 13+6 weeks, the second lasts from 14+0 to 27+6 weeks, and the third begins at 28+0 weeks. …
Read →According to SMFM 2024, a short cervix in an asymptomatic patient with a singleton pregnancy and no history of spontaneous preterm birth is diagnosed with a …
Read →The FMF 2025 model for 19–24 weeks is based on a cohort of 134,443 singleton pregnancies and assesses the risk of preeclampsia with delivery before 28, …
Read →ISUOG has released its first specialized document on POCUS in obstetrics and gynecology: online — November 2025, publication in UOG — 2026;67:116-127. The main principle: bedside …
Read →The selection of an ultrasound diagnostic course in obstetrics and gynecology relies on the training structure (undergraduate and subsequent levels), simulation technologies (VR simulators), and skill …
Read →Ectopic pregnancy remains a key urgent situation in early imaging: the narrow diagnostic window and high clinical risks require precise classification. Pregnancy of unknown location (PUL) …
Read →The IOTA/ISUOG 2026 consensus updates the basic language for describing adnexal tumors: the mass should be measured in three mutually perpendicular dimensions, separately noting the largest …
Read →According to the updated ISUOG 2025 guidelines, chorionicity should be determined at 11+0–13+6 weeks, and monochorionic diamniotic twins should be monitored by ultrasound every 2 weeks …
Read →According to ISUOG 2025, selective IUGR in twins should be suspected with significant discordance in estimated fetal weight; the threshold requiring specialized assessment is ≥25%, calculated …
Read →According to ISUOG 2024, the third trimester begins at 28+0 weeks, and routine ultrasound should be standardized: viability, presentation, 4 basic biometrics, EFW calculation, amniotic fluid, …
Read →According to the ISUOG 2025 consensus, in hypertensive disorders of pregnancy and FGR, maternal hemodynamics should be described not only by blood pressure but by a …
Read →According to the ISUOG 2026 consensus, the endometrium is primarily assessed transvaginally in the mid-sagittal plane; thickness is the double layer of the endometrium in mm …
Read →For accurate O-RADS US, the protocol must provide the morphology of the lesion in three orthogonal dimensions and a reproducible assessment of blood flow with a …
Read →According to the <a href="https://www.isuog.org/clinical-resources/isuog-guidelines/practice-guidelines-english.html">ISUOG 2025</a>, gynecological PoCUS for acute pelvic pain should address a limited set of clinical questions at the patient's bedside: is there …
Read →Prenatal ultrasound screening is structured into three periods, corresponding to international ISUOG protocols: the 11–14 week scan, routine mid-trimester scan, and third-trimester scan. Specific regulatory parameters …
Read →The revised MUSA consensus (Harmsen et al., 2022) categorizes ultrasound signs of adenomyosis into direct (myometrial cysts, hyperechoic islands, echogenic subendometrial lines and 'buds') and indirect …
Read →IOTA recommends characterizing adnexal masses using benign descriptors, the ADNEX model, and a two-step strategy, which allows assigning an O-RADS category according to the ACR classification …
Read →Routine anatomical screening of the second trimester is performed according to a standardized protocol with a systematic review of fetal anatomy, biometry, assessment of the placenta, …
Read →According to ISUOG, fetal heart screening begins with the assessment of situs, cardiac axis, and rhythm. The structural review in routine screening should include the 4-chamber …
Read →Transvaginal cervicometry is the standard for measuring cervical length when assessing the risk of preterm birth. According to ISUOG, the method is highly operator-dependent, thus a …
Read →Fetal Growth Restriction (FGR) is diagnosed based on consensus Delphi criteria (Gordijn et al., 2016), which combine EFW, longitudinal growth assessment, and Doppler parameters (uterine arteries, …
Read →Dopplerometry in obstetrics includes the assessment of the PI of uterine arteries (UtA-PI), umbilical artery (UA-PI), and middle cerebral artery (MCA-PI), as well as the calculation …
Read →Ultrasound screening at 11–14 weeks combines maternal age, nuchal translucency thickness, and assessment of the ductus venosus/tricuspid regurgitation to detect trisomies 21, 18, and 13. Evaluation …
Read →Fetal biometry includes the measurement of biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL), followed by evaluation against percentile norms by …
Read →First trimester screening according to the updated ISUOG practice guidelines (performance of 11–14-week ultrasound scan, Ultrasound Obstet Gynecol 2023;61:127–143) is performed in the window of 11 …
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