Do patients need to take progesterone if they do IVF cycle in Thailand?

Yes. The vast majority of IVF cycles require progesterone. For fresh cycles and programmed frozen cycles, progesterone is necessary because your body cannot produce enough on its own.
But there are rare exceptions. In a true natural cycle frozen embryo transfer, where ovulation occurs naturally, and the corpus luteum is fully functional, some patients may not need progesterone supplementation. 
Progesterone helps prepare and sustain the uterine lining, boosting your odds of a successful pregnancy, and nearly all patients need progesterone after embryo transfer. 
This standard practice aligns with guidelines from the American Society for Reproductive Medicine (ASRM) and the European Society of Human Reproduction and Embryology (ESHRE). 
Thai fertility clinics like CEF Bangkok always adhere to international medical standards, making progesterone luteal phase support a standard part of IVF treatment. As such, progesterone will almost always be included in your medication plan if you're pursuing IVF in Thailand. 
Learn more about [why progesterone is necessary for IVF] and how it affects your treatment outcomes.