The greatest breakthrough in ET in the past 7 years has been in the areas of super-ovulation and recipient synchronization. The use of CIDRs in donors has increased average embryo production and decreased the number of non responsive donors. CIDRs make it possible to be more efficient at flushing large numbers of donors at the same time and lining them up with large numbers of recipients. Donors can be super-ovulated if they are a minimum of 50 days post partum and cycling. The exact day of cycle is not important. I suggest you consult your ET practitioner about this method.
Recipients can be synchronized with CIDRs in small or large groups with or without heat detection. More efficient use of recipients (large groups or small) is the greatest benefit compare to using natural heats or Prostaglandins (Estrumate or Lutalyse). Pregnancy rates may be slightly lower with CIDRs, but more pregnancies will result from a group of recipients due to a lower rejection rates and tighter synchronization. This method is also excellent for the producer that has a small number of recipients to line up with a donor. I recommend that details of the synchronization method that suits you should be discussed with your ET practitioner.
The advent of Direct Transfer technology has made it possible to efficiently implant embryos into recipients with natural heats 6, 7 or 8 days previous. This works well if the ET practitioner is located in close proximity and if the recipient pool is large enough. Pregnancy rates with natural heats are generally slightly higher than synchronized heats.