C Section procedure depend on individual body or what's advice by dr/gynae during your pregnancy.
Elective C Section are planned birth method example due to having twins, baby's breech, you wish to have C section, baby's big, other health complications etc.
For most C Section they already know their date hence they are advice to go the specific date. However, there are some whereby they go natural birth instead of their C Section due to waterbag burst, contractions came in right after, fully dilated hence they don't need to go through what has been plan earlier (this is if body cooperate and they are lucky)
While on the other hand emergency c section is when all birth plan fails and you have to go emergency to save both mum and baby.
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