Hi. I am not based in Hong-Kong, I stay in Guangzhou. Anyway, I heard dr. Patrick Chan is a very good doctor but I am not sure about the IVF specialization. The names you probably heard are: prof. Milton Leung, dr. Philip Huo. Personally I go to another doctor but I didn' know what is her rate of succes. If you give me some more time (just a few weeks) I will tell you by my own experience. I'm doing the IVF these days and I will be 40 years old on May. Have a good day!