Reproductive histories of low weight girls and women

As shown in 79,000 girls and women participating in four different surveys, low body weight (less than or equal to 47.2 kg) does not prevent the attainment of menarche, conception, or even repeated conceptions. Indeed, low body weight is especially common in early maturing girls and in Puerto Ricans and Mexican-Americans. From these data, the concept of a "critical weight" for menarche is difficult to substantiate, although low body weight does have nutritional implications and is the second most important factor in regulating fetal growth.

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