I got the jadelle a week ago today and my second daughter is 4 weeks old. Family Planning told me it was fine to get it, but for the last two days my daughter has had a higher temperature, has been throwing up everything, is really unsettled and not feeding properly. The only thing I can think of that could have any affect is my jadelle. Family Planning told me would take approximately a week to kick in, which is about now. Is it possible that the implant is having an affect on my daughter?
A hormonal implant is generally not recommended for breastfeeding women, specifically in the first six weeks. I've only found mixed studies in terms of impact on breastfeeding women (inconclusive study, need further study, impact on immunoglobulin. Studies are non-existent when the use is before 6 weeks post-partum.
One thing to know is that the steroid has been identified and detected in breastmilk, but there was no significant impact on infant growth.
One study stood out in indicating that there is a higher incidence of infections:
Your best bet may be to consult actual medical advise to determine what may be causing the change in your daughter. So many things can irritate infants that it really is best left to a pediatrician / qualified medical professionals.