anal sex is a bit of a taboo subject, despite the fact that its an increasingly popular sexual activity. As more couples explore this type of sex, understanding the risks, rewards, and proper. The pain from an anal fissure can be so overwhelming that it discourages people from defecating. Having anal sex can increase the risk of bacterial infection, pregnancy, and sexually transmitted infections, and it can worsen hemorrhoids. Complications list for anal cancer the list of complications that have been mentioned in various sources for anal cancer includes metastasis death. See also the symptoms of anal cancer and anal cancer introduction. Complications and sequelae of anal cancer from the diseases database include gastrointestinal bleeding. Complications list for anal fissure the list of complications that have been mentioned in various sources for anal fissure includes permanent anal scarring - usually only if no treatment occurs. See also the symptoms of anal fissure and anal fissure introduction.