it is true that a coil being fitted would probably terminate a pregnancy. they asked me before my coil fitting was i sure i wasnt pregnant and i said i hoped not and their response was the same as your daughters gp. it is however possible to become pregnant with the coil as i have a fair few friends who have had one and had babies. your daughter should really either do a pregnancy test herself or ask for a scan to find out if she is pregnant. if she was pregnant at the time of having the coil fitted and it terminated a pregnancy there could still be traces of that pregnancy in her womb which would not be good for her health. this is why people who miscarry often have d&c's after to ensure it is all removed. also the coil can really have a big effect on periods as i only have a period maybe every 2 mths and its rarely enuf to even call a period.