Lesson 1Landmarks for early pregnancy: gestational sac, yolk sac, fetal pole, decidual reaction, and double decidual signDescribes key sonographic landmarks of early pregnancy, including gestational sac, yolk sac, fetal pole, and decidual reaction, and explains the double decidual sign, normal evolution, and expected timing by gestational age.
Normal appearance of gestational sacYolk sac morphology and size limitsFetal pole visualisation and timingDecidual reaction and double decidual signChronology of expected early findingsLesson 2Transabdominal acquisition: standard sagittal and transverse pelvic planes and uterine orientationCovers transabdominal pelvic scanning in early pregnancy, including bladder preparation, probe orientation, standard sagittal and transverse planes, and assessment of uterine position to complement transvaginal imaging or when it is contraindicated.
Bladder filling and patient positioningMidline sagittal pelvic overviewTransverse pelvic sweep and adnexal surveyIdentifying uterine version and flexionOptimising depth, focus, and gain settingsLesson 3Assessment of free fluid in pelvis: location (Morison, pouch of Douglas), quantification, and clinical implicationsExplains systematic assessment of free fluid in the pelvis and upper abdomen, including key spaces, grading volume, and recognising echogenic clot, and links sonographic findings to clinical urgency and possible ectopic rupture.
Scanning pouch of Douglas and paracolic guttersRight upper quadrant and Morison’s pouchCharacterising anechoic versus complex fluidSemi-quantitative grading of free fluidImplications for suspected ectopic ruptureLesson 4Measurements and documentation: mean sac diameter (MSD), crown-rump length (CRL), fetal heart motion and how to measure/recordDetails standardised measurements and documentation in early pregnancy, including MSD, CRL, and fetal heart rate, with guidance on calliper placement, image storage, cine loops, and reporting to support accurate dating and viability assessment.
Mean sac diameter technique and pitfallsCrown-rump length and dating chartsFetal heart rate measurement methodsImage labelling and cine loop storageIntegrating measurements into reportsLesson 5Safety, informed consent and infection control for transvaginal scanningAddresses safety principles, informed consent, and infection control for transvaginal scanning, including ALARA, chaperone use, probe covers, high-level disinfection, and respectful communication about intimate examinations.
ALARA and first-trimester safety indicesObtaining and documenting informed consentChaperone policies and patient dignityProbe covers, gel use, and barrier methodsHigh-level disinfection and traceabilityLesson 6Clinical indications, patient preparation: bladder filling protocols for transabdominal scanReviews clinical indications for first-trimester pelvic ultrasound and details patient preparation, with emphasis on bladder filling protocols for transabdominal scans, contraindications, and tailoring approach to symptoms and haemodynamic status.
Common indications in early pregnancyContraindications and relative limitationsBladder filling volumes and timingExplaining procedure and managing anxietyAdapting protocol to unstable patientsLesson 7Transvaginal acquisition: systematic sagittal and coronal views, uterine fundus-to-cervix sweep, adnexal interrogationOutlines a stepwise transvaginal scan, emphasising probe handling, systematic sagittal and coronal sweeps, and thorough evaluation of uterus, cervix, and adnexa to optimise visualisation of early pregnancy structures and pelvic pathology.
Patient positioning and probe insertion techniqueMidline uterine sagittal sweep fundus to cervixParamedian sagittal sweeps for uterine hornsCoronal plane acquisition and optimisationSystematic adnexal and cul-de-sac interrogationLesson 8Reporting language for viability, dating, and suspected ectopic pregnancy; recommended follow-up intervals and when urgent referral is neededDefines standardised reporting language for viability, dating, and suspected ectopic pregnancy, and outlines recommended follow-up intervals, red-flag findings, and criteria for urgent gynaecologic or emergency referral to support safe patient care.
Structured report elements for early pregnancyStandard terms for viability and uncertaintyDating statements and measurement reportingSuggested follow-up and repeat scan timingWhen to escalate for urgent specialist reviewLesson 9Findings suggesting ectopic pregnancy: adnexal mass characteristics, tubal ring, and non-visualised IUP thresholds and beta-hCG correlationDetails ultrasound findings that raise concern for ectopic pregnancy, including adnexal masses, tubal ring, and free fluid, and explains nonvisualised IUP thresholds, discriminatory beta-hCG levels, and integration with clinical risk factors.
Typical tubal ring and adnexal mass patternsRing of fire and vascularity assessmentFree fluid patterns and haemoperitoneumDiscriminatory beta-hCG and absent IUPPregnancy of unknown location algorithmsLesson 10Criteria to confirm intrauterine pregnancy versus pseudogestational sacExplains sonographic criteria confirming a true intrauterine pregnancy, differentiating it from pseudogestational sacs, and highlights pitfalls, timing, and correlation with clinical data to avoid misdiagnosis and inappropriate management.
Sonographic features of true gestational sacDouble decidual and intradecidual signsCentral fluid collections and pseudosacsRole of yolk sac and fetal pole visualisationCorrelation with symptoms and serial beta-hCGLesson 11Probe selection and machine presets: transabdominal curvilinear and transvaginal endovaginal transducerCovers selection of appropriate probes and presets for first-trimester pelvic ultrasound, comparing transabdominal curvilinear and transvaginal transducers, and explains optimisation of frequency, depth, and exam-specific settings.
Curvilinear versus endovaginal transducersChoosing frequency for body habitusPreset selection for early pregnancyAdjusting depth, focus, and dynamic rangeHarmonics and resolution versus penetration
