Which of the following is NOT a stage of labor?

• A. Stage zero
• B. Stage one
• C. Stage two
• D. Stage three

Answer: (A)

Understanding the stages of labor involves recognizing three formal phases: the first stage from the start of true labor contractions to full cervical dilation, the second stage from full dilation to the baby’s delivery, and the third stage from delivery of the baby to delivery of the placenta. Stage zero isn’t an official stage of labor; it’s sometimes used informally to indicate pre-labor or the very early phase, but it isn’t counted as one of the formal stages. So the option not representing a stage of labor is Stage zero.