1 Lasts 5 years.  Potential hormone side effects. There's no estrogen, so typically Mirena is less noticeable than oral birth control (the pill). The way the hormone is released via Mirena is local, so typically women don't notice changes.
The lesser sciatic foramen is an opening (foramen) between the pelvis and the back of the thigh.The foramen is formed by the sacrotuberous ligament which runs between the sacrum and the ischial tuberosity and the sacrospinous ligament which runs between the sacrum and the ischial spine.he lesser sciatic foramen has the following boundaries: 1  Anterior: the tuberosity of the ischium. 2  Superior: the spine of the ischium and sacrospinous ligament. 3  Posterior: the sacrotuberous ligament.
The sacroiliac joints are located between the lateral aspects of the sacral alae and the iliac bones. The joints consist of ligamentous and synovial components (6). The ligamentous portion comprises the superior two-thirds to one-half of the joint and is formed by the interosseous sacroiliac ligament.