This composite image illustrates a three-part medical simulation training model designed for obstetric education, specifically for teaching cervical dilatation and fetal station assessment. Panels (a) and (b) show a female pelvic mannequin torso with an open abdominal aperture. Inside the pelvic cavity, a green spherical component represents the fetal head, attached to a graduated red rod. The rod features 1 cm markings to simulate and measure 'fetal station' relative to internal palpable landmarks (ischial spines). Panel (c) displays a set of dark, rectangular bakelite plates used to simulate the cervix. These plates feature central circular openings ranging from 1 to 10 cm in diameter, allowing trainees to practice digital vaginal examinations to determine cervical dilatation. The model serves as a low-cost, effective tool for labor and delivery simulation, enabling learners to develop tactile skills in assessing the progression of labor within a standardized clinical context.

This diagnostic image consists of two side-by-side MRI scans in the coronal plane, focused on the maternal pelvis during late-term pregnancy. The images demonstrate the fetal head engaged within the pelvic canal. Key maternal anatomical landmarks include the iliac wings, the acetabula, and the ischial spines. A horizontal yellow reference line is drawn across the interspinal plane, connecting the maternal ischial spines. This line serves as a clinical marker for determining fetal station. The fetal skull is seen as a well-defined, dark, ovoid structure, with its leading part positioned at the level of the yellow interspinal line, visually confirming a fetal station of 0. This imaging is utilized in obstetrics to objectively assess the progress of fetal descent and engagement within the birth canal, comparing clinical examination findings with high-resolution radiological evidence.

**Imaging Modality:** Two-dimensional (2D) transperineal ultrasound. **Anatomical Region:** Maternal pelvis and fetal head during labor. **Observed Anatomy & Landmarks:** - **Maternal Landmarks:** The symphysis pubis is visible superiorly as a hyperechoic structure. The "infrapubic line" is represented by a solid yellow line drawn perpendicular to the long axis of the symphysis pubis. - **Fetal Landmarks:** The fetal head is visible within the pelvic canal. A "caput succedaneum" (localized scalp edema) is identified as a hypoechoic soft tissue swelling superficial to the fetal skull. **Key Measurements & Findings:** The image demonstrates the spatial relationship used to determine fetal station via ultrasound. A dotted vertical line marks the "level of the ischial spines," situated 3 cm caudal (posterior in this orientation) to the solid "infrapubic line." This 3 cm distance serves as a reference for quantifying the descent of the fetal head relative to the pelvic mid-plane. **Clinical Significance:** This intrapartum ultrasound assessment provides an objective measurement of fetal head engagement and station, differentiating the true fetal skull position from soft tissue findings like caput succedaneum.