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Published on: October 13, 2018
Frecuencia de lactancia, función gonadal y espaciado de nacimiento entre los cazadores-recolectores !Kung
Resumen
Las madres cazadoras-recolectoras del !Kung.
Área de la Ciencia:
- Biología de la reproducción Biología reproductiva.
- La Antropología Antropología Antropología.
- La lactancia humana La lactancia humana es la lactancia humana.
Sus antecedentes:
- Los cazadores-recolectores !Kung exhiben patrones únicos de espaciado de nacimiento.
- Se sabe que la lactancia influye en la fertilidad posparto, pero los mecanismos se debaten.
Objetivo del estudio:
- Para investigar la relación entre el comportamiento de enfermería y los niveles de la hormona reproductiva materna en las madres !Kung.
- Explorar el papel del intervalo de intervalo en la infertilidad inducida por la lactancia y el espaciamiento entre nacimientos.
Principales métodos:
- Se midieron los niveles séricos de 17 beta-estradiol y progesterona en las madres !Kung.
- Se registraron la frecuencia de enfermería, la duración de los ataques y los intervalos entre los ataques.
- Los datos hormonales se correlacionaron con la edad infantil, los patrones de lactancia y el estado reproductivo materno.
Principales resultados:
- Se observaron bajos niveles séricos maternos de 17 beta-estradiol y progesterona.
- Estos niveles hormonales se correlacionaron con la edad del bebé y el intervalo entre los episodios de lactancia, no con el tiempo total de lactancia.
- La supresión de la función gonadal materna parece estar mediada por la prolactina a través de la estimulación mamaria programada.
Conclusiones:
- El intervalo de lactancia, no el tiempo total de lactancia, es un factor crítico en la supresión de las hormonas reproductivas maternas.
- Este mecanismo dependiente del tiempo y mediado por la prolactina probablemente explica la infertilidad de la lactancia y el espaciado de nacimiento observado en las poblaciones !Kung.
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