What physiological change occurs as part of the lightening phenomenon?

Lightening refers to the process in late pregnancy when the fetus settles lower into the pelvis in preparation for labor. This physiological change occurs as the baby's head engages with the pelvic brim, which can typically happen a few weeks to a few days before labor begins. As a result, the mother may notice some relief in breathing discomfort, as the pressure of the fetus against the diaphragm is reduced.

While lightening can also lead to increased pelvic pressure and changes like back pain due to the fetus’s position, the primary event is the actual descending of the fetus into the pelvic region, marking an important step in the onset of labor. Understanding this phenomenon is crucial for recognizing the signs of impending labor and providing appropriate care and guidance to expectant mothers.