Study finds mums with five kids sleep the most and we need to know more

How does this work exactly?

I have two children and there's not much that anyone could do to convince me to have more. Don't get me wrong I love my kids and I've always wanted to be a parent but they can be pretty exhausting and the sleep deprivation is not fun. Most mornings I'm trying hard not to fall asleep on the bus into work after my two-year-old kept me up all night because, in her own words, her teddy wouldn't go to sleep. That being said recently I came across a study that said that mums with five children get the most sleep and I have so many questions. A study conducted by Amerisleep found that mums with five children get approximately nine hours of sleep per night on average. On top of this the findings say that dads are getting a little more sleep than mums. What's that all about? In not so great news the study also found that mothers with three children are getting the least amount of sleep. For mums like myself with two children we fall somewhere in the middle so we're not the worst off for catching some Zzzs. While the study was very informative on the numbers it didn't really answer any questions on why it is that mums with five children are able to hit the snooze button on their alarm more than most other mums. Those conducting the study did offer the suggestion that parents with more children just make sure they are getting enough sleep because they know they'll need the energy but as any parent can attest that doesn't always work. We'd all love to get a full night's sleep because we know we'll need the energy but our kids don't always allow that especially when they're very little. I guess why mothers with five kids get more sleep will just have to remain a mystery.