The body\u2019s hidden clock Every human body<\/a> runs on a natural timing system called the circadian rhythm. This system controls sleep, energy, hunger, and mood. It follows a roughly 24-hour cycle based on day and night.<\/p>\n When this rhythm stays stable, the body works well. But when it gets disturbed, problems can appear. Poor sleep, stress, or irregular schedules can affect health over time.<\/p>\n Scientists have long tried to understand when this clock begins in life. Earlier studies gave mixed answers. Some showed rhythms close to birth, while others found early signs in developing tissues. <\/p>\n This new research helps clear that confusion by showing how the clock grows step by step before birth.<\/p>\n A new discovery before birth<\/p>\n Researchers found that the circadian clock begins working inside the womb much earlier than expected. It does not suddenly switch on. Instead, it slowly builds during pregnancy<\/a>.<\/p>\n \u201cWe know that disrupting circadian rhythms during pregnancy can affect how sleep and daily rhythms develop in infants, and these early disruptions are linked to a higher risk of mood disorders such as anxiety and depression later in life,\u201d said Nikhil Lokesh, first author of the study.<\/p>\n The study shows that the baby\u2019s clock becomes stronger over time. It also starts to match the mother\u2019s rhythm as pregnancy progresses.<\/p>\n Watching a glowing clock<\/p>\n To study this process, scientists used a clever method. They worked with mice that had a glowing protein linked to a clock gene called PER2. This gene plays a key role in controlling daily rhythms.<\/p>\n As the babies developed inside the womb, this protein produced light whenever the clock was active. Special cameras captured this glow.<\/p>\n The glow increased as pregnancy continued. By tracking it, scientists could see when the internal clock became active and how it changed over time.<\/p>\n Rhythms grow step by step<\/p>\n The study showed that early in pregnancy, the rhythm is weak or unclear. But as development continues, the rhythm becomes stronger and more regular.<\/p>\n Around the later stage of pregnancy, the baby<\/a>\u2019s clock starts showing clear daily patterns. These patterns become stable and predictable close to birth.<\/p>\n The researchers also found that the clock usually peaks in activity during the early night, similar to the mother\u2019s rhythm. This shows that the baby\u2019s clock does not develop alone. It learns timing from the mother.<\/p>\n The placenta plays a key role<\/p>\n The placenta is not just a support system for nutrients and oxygen. It also helps pass timing signals from the mother to the baby.<\/p>\n The study found that both maternal and fetal parts of the placenta have their own rhythms. These rhythms change during pregnancy and help coordinate timing between mother and baby.<\/p>\n Scientists even observed wave-like patterns of clock activity moving across the placenta from maternal to fetal layers. This shows active communication inside the womb.<\/p>\n Hormones act like messengers<\/p>\n Hormones play a major role in setting the baby\u2019s clock. Glucocorticoids, which are stress-related hormones, rise and fall during the day in the mother\u2019s body.<\/p>\n These hormones pass through the placenta and act as timing signals for the baby. When researchers gave extra doses of these hormones to pregnant mice, the babies<\/a>\u2019 clocks adjusted faster.<\/p>\n The timing of these hormones also mattered. If given at different times, the baby\u2019s rhythm shifted in different ways. This shows that timing is just as important as the hormone itself.<\/p>\n What happens when rhythms fail<\/p>\n The study also found something important about development. Pregnancies where the baby\u2019s clock did not form properly often failed.<\/p>\n \u201cWe cannot yet say whether the absence of rhythms contributes to developmental problems or simply reflects them,\u201d Lokesh said.<\/p>\n Even though the exact reason is not clear, this link suggests that a working circadian rhythm may be important for healthy growth before birth.<\/p>\n Why modern life matters<\/p>\n Modern lifestyles often disturb natural rhythms. Artificial lights, night shifts, and irregular sleep patterns can affect the body\u2019s clock.<\/p>\n This becomes more important during pregnancy. Disruptions in the mother\u2019s rhythm can affect the signals reaching the baby.<\/p>\n Research shows that such disruptions may increase risks like poor pregnancy outcomes or long-term health issues in children.<\/p>\n A clock that shapes life<\/p>\n This research changes how people think about early life. The body\u2019s clock does not begin at birth. It starts forming in the womb and grows stronger over time.<\/p>\n The mother\u2019s body helps guide this process through daily rhythms and hormones. Even the placenta plays an active role in passing these signals.<\/p>\n \u201cUnderstanding when and how the body clock starts ticking helps scientists identify sensitive developmental windows when circadian disruption may have lasting effects,\u201d said Lokesh.<\/p>\n The study is published in the journal bioRxiv<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"A baby\u2019s body does not wait until birth to start learning a routine. Even inside the womb, it…\n","protected":false},"author":2,"featured_media":376044,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[134,111,139,69],"class_list":{"0":"post-376043","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-health","9":"tag-new-zealand","10":"tag-newzealand","11":"tag-nz"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/376043","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=376043"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/376043\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/376044"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=376043"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=376043"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=376043"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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