A 25-year-old women whose antenatal period was uncomplicated is in labour. She has a single foetus in cephalic presentation. The head is not engaged. The foetal heart rate is 150 beats per minute. The cervical dilatation is 5 cm, the membranes are absent and the pelvis is adequate. It is decided to perform a caesarean section immediately.Which one of the following findings is the most likely cause for this decision?

Ans. is d, i.e. Palpation of the frontal bones and the supraorbital ridgesPart palpatedPresenting part* Anterior fontanelle, sagittal suture and posterior fontanelle* Vertex* Anterior fontanelle, frontal bone, sagittal suture, supraorbital ridges or root of nose* Brow* Supraorbital ridges, Eyes, nose, mouth and chin* FaceAmongst these presenting parts:It is absolutely essential to do cesarean section in Brow because in brow, engaging diameter is Mentovertical diameter (14 cms), which cannot pass through cervix.Hence in Brow always cesarean is done. Thus during labor if obstetrician palpates, supraorbital ridges and frontal bone she should understand, it is brow presentation and take patient for cesarean immediately.