triplet birth造句

• In the uk , the number of triplet births plummeted from 2001 after the hfea imposed a limit of two embryos for most women , but the twin birth rate has remained high , which is why the expert group is calling for further action
  在英国，自从2001年hfea限制多数妇女只能一次移植2个胚胎以后，三胞胎出生人数直线下降，但双胞胎的出生率仍高居不下，这便是专家组呼吁采取进一步行动的原因了。