Three-dimensional ultrasound (3D US) is a diagnostic imaging technique that synthesizes multiple two-dimensional (2D) images into a three-dimensional volume, enabling multiplanar navigation and enhanced visualization of anatomical structures. The process involves three main phases: data acquisition, rendering, and optimization of rendered views. Data acquisition requires precise alignment of orthogonal planes to minimize processing errors, reduce motion artifacts, and magnify the target image. Rendering utilizes specialized software to analyze stored volume data and highlight target structures. It focuses on regions of interest (ROI) and applies various techniques, including surface rendering, skeletal rendering, and contrast-enhanced rendering. These techniques improve the visualization of complex anatomical structures like the fetal face or bone morphology. Optimization tools include pictorial rendering for realistic imagery, inversion techniques for highlighting anechoic structures, and curved ROI for assessing irregular shapes. Advanced applications like real-time four-dimensional (4D) US and spatiotemporal image correlation (STIC) incorporate temporal dimensions, enabling dynamic assessment of fetal movements or cardiac activity. In obstetrics, 3D US enhances fetal evaluation by optimizing insonation angles and image quality, while in gynecology, transvaginal imaging facilitates detailed uterine and adnexal assessment. 2D US remains the cornerstone of sonographic imaging in obstetrics and gynecology. Despite the routine use of 3D US not being supported by grade A evidence, this technique holds significant potential for aiding in the evaluation of obstetric and gynecological patients.