Scientists have told us how the shape of the female pelvis during the life – BBC

No matter how much scientists have struggled on the study of nature, constantly improving their methods, it still remains the biggest mystery. Researchers still do not cease to be amazed at how everything has been thought and organized in the living world

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Anthropologists and biologists from Switzerland and Belgium in the course of joint research found evidence that the shape and size of the pelvis in women can change, adapting to the appearance of progeny. Progress in research and analysis of the data published in the latest edition of the journal Proceedings of the National Academy of Sciences.

the human pelvis structure classified to sexual dimorphism, ie, differs in males and females of each other . As a rule, hips in women is wider and more rounded shape than men.

By studying the structure of the female skeleton, the scientists hypothesized so-called obstetrical dilemma. On the one hand, the female pelvis to be relatively wide to facilitate the emergence of babies born, which when properly positioned in utero are headfirst. On the other hand, a narrow pelvis facilitates human bipedalism. Recently, this hypothesis challenged on the basis of biomechanical and biocultural indicators, as well as metabolic processes. However, until the recent studies of Swiss and Belgian researchers was unclear what factors are responsible for the differences in the shape and size of the pelvis in adult men and women

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Getting to the scientific work, the researchers have put forward the following hypothesis: during the life of the structure of the pelvis in women specifically is changing, facilitating the birth of children. To test their own hypothesis, the team was invited to participate in the study of 275 women of all ages up to 95 years. The authors used the methods of computed tomography, as well as engaged in geometric morphometry, ie we analyzed the ratio of the size and shape of the pelvis parts. The findings were compared with the existing information on the basin structure in men.

The results showed that before puberty the pelvis structure in boys and girls almost makes distinctions, and all changes occur equally.

Since the beginning of active sexual development that occurs in some girls at the age of 10 years, a change in the shape and size of the female pelvis happens on its own unique laws.

The processes that prepare the female body for the birth of children, completed about 25 years. Scientists note that the period when the differences in the structure of the pelvis in women and men, the most noticeable coincides with the peak of fertility. According to the researchers, the women comes an age average of 25 to 30 years. Biologists have noticed a curious feature: at the age of 40 to 45 years, the structure of the female pelvis continues to evolve, however, change again proceed by analogy with the male. Conversion leads to a reduction in the birth canal dimensions (birth canal – a channel formed by the bones of the pelvic and placed in it the soft tissue through which the fetus and the placenta during childbirth).

The Swiss and Belgian researchers suggest that all changes in the shape and size of the female pelvis, depending on age, may be linked to hormone production during puberty and early menopause. According to biologists, the most actively involved estradiol, which is part of a group of female sex hormones – estrogens. That depends on it, as will be rounded contours of the female figure. Often estradiol called “pregnancy hormone” because it regulates blood flow in the pelvic cavity, runs an increase in uterine size, and is also responsible for the formation of the placenta.