The use of extra-amniotic saline infusion with a balloon catheter or a double balloon catheter (Atad ripener) also appears to be effective for cervical ripening.
用羊膜外单或双气囊氏导管也是宫颈成熟的有效方法。
英语百科
Balloon catheter
A balloon catheter is a type of "soft" catheter with an inflatable "balloon" at its tip which is used during a catheterization procedure to enlarge a narrow opening or passage within the body. The deflated balloon catheter is positioned, then inflated to perform the necessary procedure, and deflated again in order to be removed.