In order to produce a more powerful contraction, the brain must send a more powerful signal. (runninginsystems.com)
They discovered that repeated apneas resulted in the brain progressively triggering more powerful contraction of the respiratory muscles, which resulted in an increase in breathing. (ahealthblog.com)
The body's response may be the fetal ejection reflex resulting in very powerful contractions and a quick birth. (midwifethinking.com)