I have heard with IVF you are at greater chance of ectopic despite the fact that the emby is place directly into the uterus as it does tend to wander before finding a place to implant. You would think it would be the other way around.
As I am at a great risk of another ectopic (have one tube and it's damaged tube) I enquired about IVF to prevent another ectopic happening and they said it was no guarantee and the chances were just as great through IVF.
If you BHCG has being rising accordingly I would say your chance of ectopic is very low if no chance at all. With my ectopic my BHCG was 6000 at 8weeks which apparently was very high for an ectopic pregnancy. Not sure if thats true but thats what the consultation/surgeon told me. At 5weeks it was only 60.