A term infant delivered by vacuum extraction is noted to have a firm, well-circumscribed swelling limited by suture lines over the right parietal bone, appearing several hours after birth. Compared with forceps delivery, which statement best explains why this lesion is more characteristically seen after vacuum extraction?
- A It results from traction on the scalp producing subperiosteal bleeding ✓
- B It results from compression of the facial nerve against the ramus of the mandible
- C It represents diffuse subaponeurotic bleeding crossing suture lines
- D It represents oedema of the presenting part that resolves within days
Correct answer: A. It results from traction on the scalp producing subperiosteal bleeding
Explanation
The swelling described is a cephalhaematoma, a subperiosteal collection confined by sutures, and suction from the vacuum cup is a recognised cause of the underlying periosteal vessel injury, making it more frequent after vacuum than forceps delivery. Option C describes a subgaleal haemorrhage, which crosses sutures and is life threatening, while option D describes caput succedaneum. Facial nerve injury, option B, is the injury classically associated with forceps blades.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.