This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abnormal labor, Subject name: Gynaecology & Obstetrics
Post-term labour is seen in: 
Select and explain. 
A. Hydramnios, B. PID, C. Anencephaly, D. Multiple pregnancy
C: Anencephaly
Answer: C: Anencephaly 
Explanation: Post term labour is seen in anencephaly. Pituitary is absent. It interfers with hormonal control of onset of labour. TEXTBOOK OF OBSTETRICS, SHEILA BALAKRISHNAN, 2nd EDITION,pg:218