哺乳期に伴う骨密度の変化
M Sowers1, G Corton, B Shapiro
1Department of Epidemiology, University of Michigan, Ann Arbor 48109-2029.
JAMA
|June 23, 1993
まとめ
乳児の授乳期間が6ヶ月を超えることは,女性における重要な骨の喪失と関連しています. しかし,骨のミネラル密度 (BMD) は,出産後の12ヶ月以内に,通常,ベースラインレベルに戻ります.
科学分野:
- 生殖器保健は,生殖器の健康についてです.
- 骨代謝についてです.
- 栄養科学とは,栄養科学である.
背景:
- 哺乳期は母親の健康にとって重要な時期であり,骨のミネラル密度 (BMD) に潜在的に影響を与える可能性があります.
- 以前の研究では,母乳の骨量に対する授乳期間の長期的な影響について,異なった結果が出ていた.
研究 の 目的:
- 授乳期間と母親のBMDの変化との関係を調査する.
- 長期授乳を中止した後,BMDがベースラインレベルに戻るか否かを判断する.
主な方法:
- 出産後の12ヶ月間にわたって98人の健康な女性を対象とした前向きなコホート研究.
- 多様な時間点における二重エネルギーX線密度測定を用いて測定された近親股関節と腰椎の骨鉱質密度 (BMD).
- 授乳期間によってグループ化された参加者:0〜1,2〜5,6ヶ月以上.
主要な成果:
- 6ヶ月以上授乳している女性は,出産後の6ヶ月で平均5.1% (腰椎) と4.8% (股関節頸部) のBMD損失を経験しました.
- 0〜1ヶ月間授乳している女性では,有意なBMD減少は観察されなかった.
- 乳児授乳期間延長グループにおけるBMDの減少は,年齢,食事,体格,または身体活動に起因するものではありませんでした.
結論:
- 長期の授乳 (≥6ヶ月) は,母親の骨の損失と関連しています.
- 産後12ヶ月までに腰椎の骨質量 (BMD) がベースラインに戻ることが示唆されています.
- 9ヶ月を超えて継続された授乳は,腰椎骨髄BMDの増加を示したが,ベースラインレベルを下回っていた.
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