How Long Does Mirena Coil Implantation And Medication Take To Control Menopausal Symptoms?

Hi I have for nearly 10 years successfully had a mirena coil fitted, which in combination with Progynova 1mg has been sufficient to prevent menopausal break-through symptoms. At start of 2011 I have been experienceing hot flushes and night sweats. I presumed the coil had ended its natural life, doctor removed this and subsequently tried me on two other HRT treatments - one in patch form the other tablet. Neither were effective. I have 3 weeks ago had a new mirena coil fitted and started taking Progynova 1mg - the menopausal symptoms have not improved - is this too early to judge after only 3 weeks?

Thank you