A 32-year-old G3P2 at 39 weeks gestation is in the second stage of labour. After 90 minutes of active pushing, the fetal head is at +3 station in the right occipitoposterior (ROP) position. Fetal heart rate shows a baseline of 130 bpm with absent variability and recurrent late decelerations. The cervix is fully dilated and the perineum is bulging. The obstetrician plans instrumental delivery. Which of the following is the MOST appropriate next step?

Explanation

## Clinical Assessment **Fetal Status:** - Baseline FHR: 130 bpm (normal) - **Variability: ABSENT** ⚠️ - **Late decelerations: RECURRENT** ⚠️ **Maternal Status:** - Station: +3 (low cavity, near outlet) - Position: ROP (posterior, requires rotation) - Perineal bulging (head low) - Duration of pushing: 90 minutes (prolonged) ## Key Point: Non-Reassuring Fetal Status Takes Precedence **High-Yield:** Absent variability + recurrent late decelerations = **non-reassuring (abnormal) fetal heart rate pattern**. This indicates: 1. Fetal hypoxia and metabolic acidosis 2. Risk of fetal death or severe neonatal encephalopathy if labour is prolonged 3. **Contraindication to prolonged instrumental delivery attempts** ## Why Cesarean Section Is Correct Instrumental delivery (whether vacuum or forceps) carries: - **Risk of failed delivery** (10–15% with vacuum; lower with forceps but higher trauma) - **Time cost:** Each failed attempt delays definitive delivery - **Fetal risk:** Repeated traction and rotation in a hypoxic fetus increases intracranial injury risk **Clinical Pearl:** Although the station is low (+3) and technically amenable to instrumental delivery, the **non-reassuring FHR pattern is an absolute contraindication** to prolonged instrumental attempts. Cesarean delivery is faster and safer for the fetus in this scenario. ## Contraindications to Instrumental Delivery | Absolute Contraindications | Relative Contraindications | |---------------------------|---------------------------| | **Non-reassuring FHR** | Suspected cephalopelvic disproportion | | **Suspected fetal bone disease** (osteogenesis imperfecta) | Maternal exhaustion | | **Suspected fetal bleeding disorder** (alloimmunization, thrombocytopenia) | Prematurity <34 weeks | | **Unengaged head** (>0 station) | Suspected macrosomia | **Warning:** Do not attempt instrumental delivery in a hypoxic fetus hoping to avoid cesarean. The time spent on failed attempts worsens fetal outcome. ## Why Other Options Are Incorrect - **Vacuum extraction with rotation:** Absent variability and late decelerations are contraindications. Vacuum is also less effective for posterior positions requiring rotation. Risk of failed delivery and worsening fetal acidosis. - **Kielland forceps:** Although technically feasible at +3 station, the non-reassuring FHR pattern is an absolute contraindication. Kielland delivery takes time and carries maternal morbidity risk in a fetus that is already hypoxic. - **Outlet forceps without rotation:** ROP position requires rotation to OA for safe delivery. Delivering in ROP (face-to-pubis) increases perineal trauma and is not standard practice. Moreover, the FHR pattern is abnormal. [cite:ACOG Practice Bulletin 208: Operative vaginal delivery; RCOG Green-top Guideline 26]