Oxytocin Decreases as Age Increases?

So, I'm in my hairdresser's chair and she tells me that she read somewhere that some hormone, or something, that is really strong when women are young decreases as they get older.  (She's about 10 years older than me and her kids are grown.)  As we keep talking - she keeps calling it serotonin, but I looked it up and can't find anything like that - I decide she must be talking about oxytocin. 

Follow me here:  She was talking about when you are young, having babies, you nurture them, hold them, are so full of love, you might burst.  They are the center of your universe.  Yes, I'm with her.

Then she started talking about as they grow older, they are people that you are living with, trying to guide and set on a good path.  She said by the time they are 18, those levels of "oxytocin" have decreased significantly and you are pushing them out the door!

When my babies were little, I couldn't imagine them leaving home or ever living in separate houses, let alone in separate states!  Now, with the oldest a junior in high school, I have moments of panic, thinking, "What if he goes to a local college and wants to live at home?"  Only slightly joking.  Seriously, if these levels stayed high, how could we ever let our children go live lives of their own? 

I know of several families recently that have gone through divorce.  They all have several children.  The reason I am mentioning it is because in all of these families, the dads are the ones who are the main caretakers now.  I find it perplexing and definitely not the stereotype of the mom keeping the kids.  All of the moms are near or over 40.  Maybe there is something to this...

With that being said, I'm not one looking for an excuse to make, in my opinion, bad choices.  However, I must admit, personally, at almost 42 (the end of this month), I feel less... nurturing.  There's honesty for you.  If I had a baby tomorrow, would those levels of oxytocin surge?  I certainly hope so.  Don't worry - that ain't happening!  But with my baby at almost 8 and a house full of teenagers, I definitely don't feel oxytocin gushing love from every pore!  They were so easy to love as babies - snuggling, reading books, singing songs, breastfeeding, co-sleeping, babywearing.  Finding different ways to express love to each growing child can be challenging.

My husband, on the other hand, is much more loving and patient with the children now than when they were little.  I find it an interesting.

Every now and then I have a mom come through class who is much older, like closer to my age.  Often, they seem to have a harder time adjusting to motherhood than the younger moms.  Granted, if I was "single" without children for that many years, I feel it would be hard to adjust.  For the sake of discussion, is it possible these levels really do diminish and that contributes to things being more difficult for the "older" mother?  The flip side is that she might have the maturity and patience to handle being a mother more-so than when she was younger.

I have a sister that has never had or wanted children.  She seems to not have a nurturing bone in her body.  She might actually read this, or one of her friends might, and I think they'd all agree.  Is it possible that her oxytocin levels are so low, that contributed to not ever wanting children?

I admit, I haven't looked this up.  I've done no research on this topic.  This post stems from a conversation at the beauty shop.  But there were parts of it than rang true to me.  I thought I might throw it out there and see what y'all thought.  Think of your own mothers.  And, I guess, in some cases, try to do better.  Find new ways to love your babies, even when they can't sit in your lap anymore.