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Photo: Sunflower, Joshrowe, Pixabay<\/p>\n
Why do women gain more weight during pregnancy than the size of the fetus? Because of small intestine growth apart from the growing off-spring.<\/span><\/span><\/strong><\/p>\n Although pregnancy is a natural stage for females and generally does not require specific treatment if both the mother and child are healthy, the bodies of many female animals, including humans, undergo significant changes during reproduction. For example, the heart shifts position upwards, while the urinary tract narrows and moves downward. <\/span><\/span>Recent research from the Francis Crick Institute, published in the highest-impacted journal ,,Cell\u201d , reveals that in mice, the small intestine may increase in length by approximately 18% by the end of pregnancy, a change similar to that seen in lactating females. Notably, this lengthening is already evident by <\/span><\/span>d<\/span><\/span>ay 7 of pregnancy in mice, according to the study’s findings<\/span><\/span>.<\/span><\/span><\/span><\/span><\/span><\/span><\/p>\n Natural limits of reproduction<\/span><\/span><\/span><\/span><\/strong><\/p>\n The entire pregnancy in mice lasts about 20 days, while women carry their babies for approximately 9 months. This difference is due to the longer development time required for human fetuses. Mice give birth to offspring that are not fully mature, which means that their young need more time and care to become independent, especially with their lifespan. <\/span><\/span>In line with many studies, as scientists write in their paper, t<\/span><\/span>he intestine is a remarkably plastic organ: its epithelium is the fastest self-renewing tissue in mammals. In the small intestine, proliferating cells located within crypts give rise to cells that migrate upward into the villus and differentiate. <\/span><\/span>It is a superficial paradox that slimmer women tend to get pregnant more easily than those with higher fat tissue. However, fat does impact fertility and thus the potential for conception.<\/span><\/span><\/span><\/span><\/p>\n The<\/span><\/span> r<\/span><\/span>eproductive growth of the maternal intestine and other organs was suggested nearly 100 year<\/span><\/span>s ago<\/span><\/span>\u00a0and has since been shown to involve increases in intestinal length and absorptive <\/span><\/span>area,<\/span><\/span><\/span><\/span><\/em><\/strong><\/p>\n c<\/span><\/span>laim <\/span><\/span>Irene\u00a0Miguel-Aliaga<\/span><\/span><\/strong> and Tomotsune\u00a0Ameku<\/strong> of The Francis Crick Institute.<\/span><\/span><\/span><\/span><\/p><\/blockquote>\n What does it mean? <\/span><\/span>Although the specific mechanisms underlying the process are not in-depth known, yet, reasons may include nutrients and microbiota. The latter ones are changing along with changes in the environment living organisms <\/span><\/span>share<\/span><\/span> and consume. <\/span><\/span>And all of this brings consequences for reproduction action.<\/span><\/span><\/span><\/span><\/p>\n I<\/span><\/span>s pregnancy evolving into <\/span><\/span>a <\/span><\/span>more energy-dense process?<\/span><\/span><\/span><\/span><\/strong><\/p>\n P<\/span><\/span>regnancy is an effort for <\/span><\/span>the <\/span><\/span>female organism. Yet, previous studies have <\/span><\/span>shown that remodeling of the maternal intestine is not confined to mammals<\/span><\/span>. For example, as scientists write, the intestine of oviparous\u00a0<\/span><\/span>Drosophila<\/i><\/span><\/span> fruit flies, which differs between males and females, grows and is metabolically remodeled in females during reproduction. What\u2019s interesting, is that intestinal growth is anticipatory and genetically-controlled. In general, the gut tract’s work and shape are driven by specific hormones that play crucial roles in the digestive process as well as preserving the functions of the cells responding to a protein trigger obtained during millions of years of evolution. However, this does not imply some pieces remain completely stiff. <\/span><\/span> S<\/span><\/span>cientists observed accelerated migration of the enterocyte progeny up the villus in early pregnancy and, particularly, lactation. What\u2019s new<\/span><\/span>\u00a0<\/span><\/span><\/strong>is that<\/span><\/span>\u00a0the researchers stated that the first pregnancy enables full reversibility of anatomical changes induced with pregnancy, while the\u00a0<\/span><\/span>subsequent<\/span><\/span><\/strong>\u00a0ones make the\u00a0<\/span><\/span>process<\/span><\/span><\/strong>\u00a0more difficult. Why? As scientists claim, villi grow during pregnancy by increasing the proliferation of their progenitors and the migration and size of differentiated epithelial cell<\/span><\/span>s<\/span><\/span>.<\/span><\/span><\/span><\/span><\/p>\n Consistent with the dynamics of villus growth\/shrinkage, these reproductive changes in epithelial cell dynamics are already apparent in early pregnancy, peak at the end of pregnancy, persist in lactation, and yet are fully and rapidly reversible post-lactation,<\/span><\/span><\/span><\/span><\/em><\/p>\n s<\/span><\/span><\/span><\/span>ay <\/span><\/span><\/span><\/span>Tomotsune\u00a0Ameku<\/span><\/span><\/span><\/span><\/strong> and Irene Miguel-Aliaga<\/strong> of The Francis Crick Institute.<\/span><\/span><\/span><\/span><\/p><\/blockquote>\n Experiments indicate that the remodeling of the villus is specific to reproductive status. According to scientists, the height, width, and depth of the villus\u2014which is responsible for absorbing nutrients and eliminating unnecessary or harmful food components\u2014return to their pre-pregnancy values. Notably, the height of the villus remains similar between the first and second pregnancies, in contrast to changes observed in gut elongation.<\/span><\/span><\/span><\/span><\/p>\n","protected":false},"excerpt":{"rendered":" Photo: Sunflower, Joshrowe, Pixabay Why do women gain more weight during pregnancy than the size of the fetus? Because of small intestine growth apart from the growing off-spring. Although pregnancy is a natural stage for females and generally does not require specific treatment if both the mother and child are healthy, the bodies of many […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[10,1,6],"tags":[],"class_list":["post-792","post","type-post","status-publish","format-standard","hentry","category-health-security-in-a-nutshell","category-healthmedical-security","category-medicine-in-a-nutshell"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=\/wp\/v2\/posts\/792","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=792"}],"version-history":[{"count":3,"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=\/wp\/v2\/posts\/792\/revisions"}],"predecessor-version":[{"id":808,"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=\/wp\/v2\/posts\/792\/revisions\/808"}],"wp:attachment":[{"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=792"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=792"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/evolutionandsecurity.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=792"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}