It goes without saying that having kids can be draining, physically and mentally. Making the transition into motherhood at first is a complete shock to the system. No matter how many people tell you to prepare for those long, sleepless nights, you'll never be ready for the intense sleep deprivation and exhaustion. Some babies sleep like logs, while other babies wake up every hour on the hour for months on end. In some cases, it can be difficult enough that parents choose to forgo having any more children. However, according to a recent study by AmeriSleep, the more kids a woman has, the more shut-eye she gets.

Yep. It sounds totally bizarre. Researchers looked at data collected by the American Time Use Survey, to see if they could gain a deeper insight into the sleeping habits of moms and dads in America. Surprisingly, it was discovered that on average parents were getting a solid eight or nine hours a day. Dads reportedly fair better with one child, gaining 8.8 hours of sleep a night. When the family grows by another one or two, this goes own to 8.6 hours. Dads with four or five kids get 8.4 hours. Moms, on the other hand, get their best sleep after they've had four or five kids for an average of 8.9 hours.

So, how does this work? How are moms that have five lots of lunches to make and ten pairs of tiny shoes to find able to get more sleep than moms who only have one child to care for? Well, it's not as cut and dry as it seems. The study doesn't just take into consideration the average amount of sleep per night, but per day.

Sleep-related activities such as napping or dozing off during the bedtime hour also had an impact. Moms of four or five children reported more of these activities, probably due to sheer exhaustion.

While getting almost 9 hours of sleep a day sounds great, moms of five are probably so tired that they could do with double that to function normally. You've just got to get it where you can, mamas!

Related: Couples Are Getting 'Sleep Divorces' To Save Their Marriage