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Cambios en la densidad ósea con la lactancia
M Sowers1, G Corton, B Shapiro
1Department of Epidemiology, University of Michigan, Ann Arbor 48109-2029.
JAMA
|June 23, 1993
Resumen
La lactancia prolongada de más de seis meses está relacionada con una pérdida ósea significativa en las mujeres. Sin embargo, la densidad mineral ósea (DMO) generalmente vuelve a los niveles basales dentro de los 12 meses posteriores al parto.
Área de la Ciencia:
- Salud reproductiva y salud reproductiva.
- Metabolismo óseo Metabolismo óseo.
- Ciencias de la Nutrición Ciencias de la Nutrición
Sus antecedentes:
- La lactancia es un período crítico para la salud materna, potencialmente impactando la densidad mineral ósea (DMO).
- Investigaciones anteriores han dado resultados mixtos con respecto a los efectos a largo plazo de la duración de la lactancia en la masa ósea materna.
Objetivo del estudio:
- Investigar la relación entre la duración de la lactancia y los cambios en la DMO materna.
- Para determinar si la DMO vuelve a los niveles basales después del cese de la lactancia materna prolongada.
Principales métodos:
- Estudio de cohorte prospectivo en el que participaron 98 mujeres sanas durante 12 meses después del parto.
- Densidad mineral ósea (DMO) del fémur proximal y la columna lumbar medida mediante densitometría de rayos X de doble energía en varios momentos.
- Participantes agrupados por duración de la lactancia: 0-1, 2-5 y 6+ meses.
Principales resultados:
- Las mujeres que lactaron durante más de 6 meses experimentaron pérdidas medias de DMO del 5,1% (columna lumbar) y del 4,8% (cuello femoral) a los 6 meses después del parto.
- No se observó pérdida significativa de DMO en mujeres lactantes durante 0-1 meses.
- La pérdida de DMO en el grupo de lactancia prolongada no fue atribuible a la edad, la dieta, el tamaño corporal o la actividad física.
Conclusiones:
- La lactancia prolongada (≥6 meses) se asocia con la pérdida ósea materna.
- La evidencia sugiere un retorno a la DMO basal en la columna lumbar en 12 meses después del parto.
- La lactancia continuada más allá de 9 meses mostró un aumento de la DMO de la columna lumbar, pero se mantuvo por debajo de los niveles basales.
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