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Vera Sizensky

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Is This Really the Reason My Daughter Won’t Sleep Through the Night?

Clean diaper, full belly, peaceful white noise, the softest pajamas on the planet and the scent of soothing lavender after a calming bath—she should be sleeping, but Lena, my 7 1/2-month-old, is working the night shift. When my daughter wakes in the middle of the night, I always assume it’s because one of the perfect sleep ingredients listed above has gone awry. But according to a new study out of Harvard University, I am wrong. 

The study’s author, David Haig, explains that the REAL reason babies wake in the middle of the night is “to delay the birth of another sibling.”I know what you’re thinking: What? How?   

Well, the study’s findings suggest that night waking, which increases in the second half of the first year of infant life, is an ecological adaption in an effort to extend amenorrhea, a mother’s post-birth infertility. Apparently a baby's late-night cries for food suppress a woman's ovarian function. And, according to the study, infants are programmed to do this because they benefit from more attention and less competition from a sibling. 

If you’re scratching your head—like I am—consider this: "Spacing out siblings would give the mother more time to recover from the birth and make young children more independent, boosting their chances of survival, so this research makes perfect sense," Siobhan Freegard, founder of British parenting website Netmums, told The Daily Mail. 

I suppose it could be true. I guess I need to have a serious chat with Lena. I’m nowhere near ready to have another baby, so she can stop all of these efforts to extend amenorrhea and just sleep through the night. Done. Simple. I’ll let you know how that conversation goes. 

Is your little one still waking at night? What’s your take on the study’s findings? 

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