臨床婦人科産科60巻5号

2006年05月発行

今月の臨床 早産─予防と対策

早産における子宮収縮の機序

著者： 熊澤恵一¹ 木村正¹

所属機関： ¹大阪大学大学院医学系研究科器官制御外科学（産科学婦人科学）

ページ範囲：P.728 - P.733

はじめに

　早産は児の生命を危機にさらし，あるいは脳性麻痺などの後遺症を引き起こし，かつ完全なる予防，治療がが不可能な，きわめて重要な疾患である．また，近年増加傾向にある．先進国では早産の頻度は全分娩の5～10％にも上る．わが国の早産率は，ほかの先進国に比べ低く，全分娩の5％である．厚生労働省の人口動態統計によると，妊娠32週から36週までの早産は1980年の3.6％から2002年の4.7％まで増加し，妊娠28週から31週までの早産は0.4～0.5％と微増している．妊娠28週未満の超早期早産も0.13％から0.23％と漸増している．周産期医療の進歩により，人工早産が増加していること，不妊治療後の多胎妊娠なども，この増加の一因となっている．

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