The factors that affect the process of labor and birth, known commonly as the five Ps, include all except:

Choice A rationale
Bladder distention may cause discomfort and urinary issues but is not directly related to cervical dilation and effacement, which involve changes in the cervix to prepare for labor.
Choice B rationale
False labor involves irregular contractions that do not lead to cervical dilation and effacement. These are often called Braxton Hicks contractions and do not result in significant cervical changes.
Choice C rationale
The cervical mucus plug coming out, also known as the "bloody show," indicates that the cervix is beginning to dilate and efface, which are preparatory processes for labor to occur.
Choice D rationale
Lightening refers to the descent of the baby into the pelvis, which typically occurs in the later stages of pregnancy and does not directly involve cervical dilation and effacement processes.

Choice A rationale
Fetal sleep cycles cause temporary decreased variability in FHR, typically lasting 20 minutes or less. FHR baseline remains normal. Normal FHR variability is 6-25 bpm.
Choice B rationale
Head compression during contractions leads to early decelerations in FHR, not decreased variability. Early decelerations are a normal response to pressure on the fetal head.
Choice C rationale
Fetal hypoxemia causes decreased variability but usually persists for longer than 20 minutes. It indicates compromised oxygen supply, requiring immediate intervention.
Choice D rationale
Umbilical cord compression leads to variable decelerations in FHR rather than decreased variability. These decelerations vary in onset, duration, and intensity.