Bleeding or spotting later in pregnancy may be a sign of a serious problem, like: 1  Preterm labor. This is labor that happens too early, before 37 weeks of pregnancy. 2  Placenta previa. This is when the placenta lies very low in the uterus and covers all or part of the cervix. 3  Placental abruption.
Afferent definition, bringing to or leading toward an organ or part, as a nerve or arteriole (opposed to efferent). See more.
In the peripheral nervous system, an afferent nerve fiber is the nerve fiber (axon) of an afferent neuron (sensory neuron). It is a long process (projection) extending far from the nerve cell body that carries nerve impulses from sensory receptors or sense organs toward the central nervous system.his process is carried out through the activity of afferent neurons (sensory neurons), interneurons, and efferent neurons (motor neurons). A touch or painful stimulus, for example, creates a sensation in the brain only after information about the stimulus travels there via afferent nerve pathways.