It is absolutely true that OBs take overnight call and work 36+ hour shifts. Students did this q4 during my 3rd year clerkship. Residents do this at least q4, sometimes q3 at my institution. Call is brutal, and involves very little sleep compared with other specialties. Every OB resident I have ever met is grouchy and sleep deprived. Unfortunately, things don't get much better when you are an attending, because you still have to stay up all night frequently for deliveries. ALso, then you have to contend with law suits, often for things you have no control over. Someone once described OB to me as "maximum responsibility with minimal control", meaning you have very little control over how and when the delivery occurs, but in the eyes of the patient, public and often times the law you are 100% responsible if anything goes wrong. I was actually quite surprised with this statement until I did my clerkship and realized that the medications we use to induce labor and stop pre-term labor are actually very ineffective. The birthing process is a powerful force that cannot be easily tampered with, except with c-section. THe only saving grace OB has is that deliveries are a very positive, enjoyable experience for many patients, and it is rewarding to be involved in this experience.