Research carried out at St Mary’s Hospital showed that natural cycle or hormonally controlled protocols for frozen embryo transfer are equally effective in terms of implantation rate and pregnancy outcome in women with regular menstrual cycles.  At Manchester Fertility we advise patients to have natural cycle frozen embryo transfers if their menstrual cycle is regular.  The reason for this is that it is easier for the patient as the cycle is monitored from home using an ovulation prediction kit and minimises the need to attend the clinic.