Hi ! Hcg injection is generally given to maintain pregnancy in the 1st trimester and extended to other mnths if needed, provided the hcg level during pregnancy is below nrml. But if the hcg level is with in normal range, u need not go for hcg injection and pregnancy can be maintained nrmly. As its a hormone injection has its own side affects, not much to the baby but to the pregnant women, like rapid wt growth, hirsutism etc, But protecting the preganacy is more important than side affects unless dangerous condition arises which is not generally seen.