A 28-year-old primigravida at 39 weeks gestation presents to the labor ward with regular uterine contractions occurring every 3–4 minutes, each lasting 45–50 seconds. On vaginal examination, the cervix is 6 cm dilated, 80% effaced, and the fetal head is at −1 station. The patient reports moderate pain and requests epidural analgesia. Fetal heart rate is 140 bpm with normal variability. What stage and phase of labor is this patient currently in?

Explanation

## Current Stage and Phase Identification **Key Point:** The patient is in the **first stage, active phase** of labor. The active phase is characterized by cervical dilation of 4–7 cm (or 3–7 cm in multiparas) with regular, progressively stronger contractions. ### Diagnostic Criteria Met | Feature | Patient Finding | Active Phase Criterion | |---------|-----------------|------------------------| | Cervical dilation | 6 cm | 4–7 cm | | Contraction frequency | Every 3–4 min | Every 2–5 min | | Contraction duration | 45–50 sec | 40–60 sec | | Cervical effacement | 80% | >50% | | Fetal station | −1 | Variable (head descending) | **High-Yield:** The **three phases of the first stage of labor** are: 1. **Latent phase**: 0–3 cm dilation, mild contractions (5–20 min apart), patient may be ambulatory 2. **Active phase**: 4–7 cm dilation, moderate contractions (2–5 min apart), patient requests analgesia 3. **Transition phase**: 8–10 cm dilation, strong contractions (1–2 min apart), patient may have nausea/rectal pressure **Clinical Pearl:** The patient's request for epidural analgesia and moderate pain are typical features of the active phase. By transition, pain is severe and the urge to push becomes overwhelming. **Mnemonic: LAT** — **L**atent (0–3 cm, **A**ctive (4–7 cm), **T**ransition (8–10 cm) ### Why Not Other Phases? - **Latent phase**: Cervix would be ≤3 cm; contractions would be milder and more infrequent (5–20 min apart) - **Transition phase**: Cervix would be 8–10 cm; contractions would be stronger (1–2 min apart) and patient would report severe pain and rectal pressure - **Second stage**: Begins at full cervical dilation (10 cm); this patient is only 6 cm dilated [cite:Williams Obstetrics 26e Ch 16]