Because when many of you get the hysterosalpingogram (HSG) report, you ask the question: Where is the site of tubal obstruction? Why is it necessary to know the site of obstruction? Because people generally think that laparoscopy is needed for obstruction at the umbilical end of the fallopian tube; tubal intervention is needed for obstruction at the proximal end of the fallopian tube or the isthmus; in other cases, such as obstruction in the open or extremely open, they don’t know where the obstruction is and they don’t know what to do. It is usually the interstitial, isthmus, and jugular abdominal obstruction, as well as cystic adhesions, occlusion, or fluid accumulation that indicate which site. In general, the difference in the degree of patency of the fallopian tubes, and not the location of the blockage, is referred to as poor patency, poor patency, and very poor patency. In fact, the conditions suitable for SSG (or tubal intervention) mainly include (but not limited to): 1) interstitial tubal obstruction; 2) tubal isthmus obstruction; 3) open but poorly patent tubes; 4) open but very poorly patent tubes; 5) poorly visualized tubes; 6) high tubal tone, slightly open or open or very poorly patent tubes; 7) mild adhesions at the umbilical ends of the tubes, open but very poorly patent tubes, etc.