rigidity of soft birth canal

...Premature rupture of the membranes occurs after the onset of labor and before the cervix has fully opened, but is now considered to be of little concern.
[Rigidity of soft birth canal]
This refers to cases where the parts through which the fetus passes, such as the cervix and vagina, are hard and do not open easily even when there is labor pain. Women who give birth for the first time at age 35 or older are called elderly primiparas, and this soft birth canal is frequently found.

*Some of the terminology that refers to "rigidity of soft birth canal" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…陣痛開始後で，子宮口が全部開く前に破水するものを早期破水というが，今日ではほとんど心配ないとされている。
［軟産道強靱rigidity of soft birth canal］
　子宮口や膣などの胎児が通過する部位が硬くて，陣痛があっても容易に開かない場合をいう。35歳以上で初めてお産するものを高年初産婦とよぶが，この軟産道強靱の頻度が高い。…

※「rigidity of soft birth canal」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報