I wouldn’t worry what she has been taking, but I would get the implant removed for sure. I completely believe your daughter that it makes her moody. However, consider that she feels more moody on the BC she is taking PO also, she may not have the timing right. I felt out of sorts when a doctor put me on pills that were different doses through the month. The idea was to take lower quantities of hormones. I never had one bad side effect on regular highish doses of BC pills any other time. I took the pill 10 years with a break and starting up again in the middle and i never gained weight, zero change in my period, except that it was a perfect 28 days apart, no chenges in my breasts, nothing. But, that triphasal pill was awful.
I cannot see one good reason to be on both meds. That just seems absurd to me. From what I have read there is a slight increase in breast cancer risk for young women taking birth control, but after they stop the numbers go back down, and over time they go back to the same stats as women who never took them. But, I know that sounds unclear, it is unclear to me too. I don’t really know what ages the test subjects started birth control, family history, how many years they took it, etc. There does seem to be some protection from endometrial and ovarian cancer with BC. I would do some of your own research, I would not trust a doctor to decide if it increases her cancer risk. The general feeling among doctors in my opinion is the BC hormones don’t hurt young people and it is way less taxing on the body than a pregnancy. They don’t think long term, they just know their 17 year old patients have never had a stroke or cancer. I know medical science of course has looked at risks, but doctors tend to accept something as safe if it is standard of care and approved. Your daughter has specific risks you are concerned about.
I once noticed on a blood test my platelets were almost outside of normal range, very high normal, and I asked if it might be from the pill and was told no. I was very young and let it go. Now I realize my platelets are never that high, and I no longer take the pill. I doubt it is a coincidence, I am at risk for DVT. I wish I had access to more of my old records to see if I had been consistently high on the platelets while on the pill.
I think if you will worry about the breast cancer risk she should seriously consider not taking the pill, only because if God forbid she gets breast cancer young it will torment the two of you. You will always wonder.
You know I am not a doctor, a lot of my answer has to do with how I know I worry in my mind, which partly has to do with my distrust of medical doctors, so keep my answer in perspective regarding where it comes from and my own anxiety levels. Maybe Komen or some other breast cancer websites have more information on any relationships of the pill and breast cancer. Or, pubmed of course might cite some studies. But, for years I though HRT for women could not be all buteerflies and flowers like they touted it, and eventually there were studies to prove my gut feeling was correct. So, you have to go with your gut sometimes to avoid regret.