母乳育児中の女性の血中ホルモンの推移  [in Japanese] An examination of the transition of hormones in the blood of women during lactation  [in Japanese]

本研究では母乳育児を継続している10名の女性の,分娩直後から産後12ヵ月までの血中ホルモン濃度の推移を検討した。血中ホルモンとしては,エストラジオール,プロラクチン,LH,FSHに着目し,産後2日目,産後1ヵ月,3ヵ月,6ヵ月,9カ月,12ヵ月目の合計6回測定した。10名の女性のうち,4名はそれぞれ産後6ヵ月目,8ヵ月目,10ヵ月目,12ヵ月目に月経が再開した。月経が再開した対象者を「月経再開群」,産後12ヵ月までに月経の再開がなかった6名を「月経なし群」とした。血中エストラジオールは,両群ともに産後1ヵ月には減少するが,「月経再開群」は産後3ヵ月から上昇傾向を示した。「月経なし群」は産後12ヵ月まで低値を維持したままであった。母乳育児中の女性のプロラクチンは,産後12ヵ月まで徐々に減少傾向を示すが,1日の授乳回数の影響をうけ,授乳回数の減少とともにプロラクチンの低下が進行し月経が再開する。

The purpose of this study was to examine the transition of hormones in the blood until 12 months postpartum, in women during lactation. The transition of estradiol, prolactin, luteinizing hormone(LH) and follicle-stimulating hormone(FSH) in blood were determined, in ten women during the period of breastfeeding. We measured the hormones in blood during the puerperium on the 2nd day, one month, three months, six months, nine months, and 12 months postpartum. It was confirmed that four women among ten women resumed menstruation at six months, eight months, ten months and 12 months after giving birth. While the estradiol in all women decreased one month of postpartum, that in four women who had resumed menstruation increased at three month postpartum. Estradiol remained low during the period of breast-feeding and six women with amenorrhea until 12 months post-partum. Prolactin declined gradually until 12 months of the puerperium. The trend was strongly related with the number of times of daily breast-feeding.