Emergency cesarean is one that isn't planned, and is often the case if something happens during labour, such as heart rate decreases or a non progressive labour (mine was the latter). You're not booked in and you're taken straight through to theatre.
an elective section is one that is planned for a particular reason, such as health implications or at the request of a pregnant woman. The pregnant woman will be given a date for this and admitted into hospital at this time.
Yours will be an elective because you have a health implication. As vaginal birth is out of the question they know that you need a section, so you'll be booked in or monitored and the section will be planned.
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