hi i havent had this happen to me personally but as far as i know this is the kind of thing that is a one off and not because of 'you' as such.
with my first, she had a true knot in her cord, which could have been fatal but fortunately she was born healthy with no problems. i heard this was common if the cord was longer than average, so i was concerned that i make long cords!! i was reassured by midwife that this kind of thing was too a one-off and very very unlikely to happen to me again.
i think if it was something that was likely to happen again they would have told you at the time, and definitely it would be in your notes so the idwives would point it out to you that it may be a concern (if it was).
im not midwife or expert but maybe try googling it ?
sorry i can tbe more help but im sure youll be fine x