When a woman goes into labor during childbirth, the cervix expands which sends a signal to the pituitary gland to release oxytocin which results in more contractions which results in more oxytocin being released and so on. what is happening during childbirth?

A positive feedback loop.

Explanation:

During child birth, a positive feedback loop is generated.

During child birth, the cervix expands which results in releasing more oxytocin from the pituitary gland. With the release of more oxytocin results in more contraction which in turn results in further release of oxytocin and it continues as such.

Thus it seen that a positive feedback loop is generated in the brain which results in more release of oxytocin hormone and as a result more contraction.

Thus the answer is "A positive feedback loop".

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