The advantage of the natural cycle is that there is no need to take hormones. Nevertheless, it should be noted that even though progesterone supplementation is not necessary for the natural cycle protocol, many IVF units add progesterone support after embryo transfer. A recent study demonstrated that adding progesterone to the natural cycle increased the live birth rate (Bjuresten et al. 2011). Patients were monitored from day 10 to 14 for follicular development after which daily home urinary kits were provided to detect the LH surge. Three days after detection of the LH surge thawed embryos were transferred and patients in the study group commenced taking vaginal progesterone.