Final answer:
The latent phase of labor is characterized by mild contractions lasting 20 to 40 seconds.
Step-by-step explanation:
The latent phase of labor is characterized by contractions that are mild and lasting 20 to 40 seconds.
During this phase, uterine contractions may occur every 3-30 minutes and gradually become more frequent and regular. These contractions help to stretch the cervix and prepare it for labor.
By the end of the latent phase, contractions may occur as frequently as every 1.5-2 minutes and last for a full minute, indicating the transition into active labor.