Wednesday, May 30, 2012

Whose Birth-Day Is It, Anyway?

Yes, I am pregnant.
As you can imagine, birth is kind of looming large on the landscape of my thoughts these days.  Between witnessing a beautiful one (my neice's) last week, and my own "coming up" sometime in the next 3, it's kind of always there.  We went to Barnes & Noble for a family outing on Memorial Day and instead of raiding the young adult fiction (Brotherband Chronicles, Book 2, was calling my name... and there were all the rest of the 39 Clues I haven't read...), between readings of Eric Carle and Mo Willems (E's new favorite characters are "Gerald" and "Piggy"), I was devouring baby-books... books on what to buy where, books for calming squawkers, pregnancy books...

One question I've been wanting answering is, of course, when will he come?  And of course as I take all the little "how far are you from labor?" quizzes in the pregnancy journals, I'm hoping the answer is "pack your bags, mama!  It's gonna be SOON!"  Because, folks, I'm getting pretty sore.  Standing up takes lots of thought ("use your arms and legs, NOT your abs!") and maneuvering, and then there's that painful moment where the weight of my full uterus falls on my ligaments and I just have to take it like a man, er, woman... the whole "hours-to-fall-asleep-despite-exaustion" scenario that is getting SO OLD... the head-in-my-bladder sensation... the "if-I-itch-any-more-I-won't-have-belly-skin-left" realization... you get the point.  It's called "bearing children in pain" for a reason that FAR outstrips labor. (This sermon, "To be a Mother is a Call to Suffer," has stayed with me ever since I read it 11 years ago.)

First of all, though, I do take lots of joy in knowing that my Father knows my son's birthday (He knows all the birthdays of all the kids I'll ever have, which blows my mind).  Before a single day of life has come to be for William Christopher, they've all been written in His book (Psalm 139).  It's been surprisingly easy to calm my heart and wait patiently this time around, trusting that "good things come to those who patiently wait," and that the Lord whose voice makes the deer give birth is going to bring my baby forth in His timing.  Looking at how fast Eowyn is growing and changing, really, 3 more weeks is just not very long at all.  Bear with me, here, I know I risk stepping on some toes:  If we are honest, how much of our discomfort the last weeks of pregnancy is from impatience?  We Westerners sure love our schedules and our control of them. Instead of being content to wait and trust as women around the world always have (without a choice, lol), we take matters into our own hands and try and force the result we want.  It's a hard thing to wait without knowing.  (It was definitely the hardest part of my long labor with Eowyn!)  But faith isn't sight.  That's the whole point, right?  If we knew, we wouldn't have to trust.  [Please note that I know there are other factors that sometimes DO and should play into the artificial induction of labor-- mom's health, baby's health, even occasionally valid schedule considerations.]

I also firmly believe that the last few weeks of a pregnancy are vital to baby's health.  He's not JUST getting fatter in there-- his brain is growing.  Check out this poster from the March of Dimes on brain maturation the last 4 weeks of pregnancy.  "A baby's brain at 35 weeks weighs only 2/3 of what it will weigh at 39-40 weeks."  Wow.  It's one thing if a baby comes "early" on its own --it's quite another for us to artificially force it.  My working theory is that babies develop in the womb at just as varying paces as they do out of it-- some babies walk at 9 months, others at 15, for example.  So why wouldn't some "microwave babies" have ready-for-birth brains at 36 weeks, while other "crock-pot babies" need a full 41 weeks?  Still, I kind of want to know how our bodies know that "it's time."  Does the placenta just reach a time-release and start kicking baby out?  Does baby somehow let the cervix know "hey! my brain and lungs are ready! let me out!"?

Biologically, this topic is fascinating.  I've been Googling (and Google-scholaring) away trying to read up on what mechanisms play into setting labor into motion.  It's a natural process that has worked really rather well for the past couple thousand of years-- and how many sheep do you know that have to be induced?-- it's just been lately that we've all gotten fixated on "due dates" and counting weeks and making sure babies come at the time appointed a quite arbitrary best guess.  Obviously, there's a reason that babies come when they do-- what is it?  As far as I can tell, most doctors and scientists say "we don't fully know." (And obviously, sometimes the system, whatever it is, short-circuits out, and babies are born too soon.) One thing that's becoming clearer, though, is that the baby really plays a big role.  You might say they help pick their own birthday in quite a big way.

He's not so obvious from the front.
This article from 1996 talks about research done in rhesus monkeys (similar in many ways to humans).  Researchers found that when the hormone androgen, which is made by fetal adrenal glands, was artificially increased in the placenta earlier than normal in pregnancy, it set "off a chemical chain reaction through the placenta to the mother's blood, resulting in premature labor and live delivery of healthy babies."  But what do adrenal glands have to do with being ready to be born?

This (quite technical/tedious) paper comparing sheep & human pregnancies & labors explains that in both sheep & humans, the fetus' hypothalamus-pituitary-adrenal system puts out increasing amounts of cortisol, which increases prostaglandins, in turn ripening the cervix, causing contractions, and changing the placental blood flow.  However, while in sheep the placenta provides the androgens needed for these changes to start, in humans, it comes from the baby's (and in part the mom's) adrenal glands.  Cortisol is a steroid hormone made by the adrenal glands that triggers lung development in the unborn baby, so he's ready to breathe air.

This rather technical Special Feature article from Molecular Endocrinology, and this abstract ("Molecular Insights into the molecular endocrinology of parturition") gives some clues that the baby's maturing lungs play a big role:
"augmented production of SP-A by the maturing fetal lung near term provides a hormonal stimulus for activation of a cascade of inflammatory signals within the maternal uterus that culminate in the enhanced myometrial contractility leading to parturition. This hormonal signal, which is transmitted to the uterus by fetal macrophages, reveals that the fetal lungs are sufficiently developed to withstand the critical transition from an aqueous to an aerobic environment."  Translation:  Baby's lungs send a hormonal message to Mom's uterus that they are ready to breathe air, and the uterus starts contracting.   
"Our findings, therefore, indicate that SP-A secreted into amniotic fluid by the maturing fetal lung serves as a hormone of parturition."  Translation:  this hormone signal travels through the amniotic fluid to reach Mom's uterus.

So, instead of sitting around hating the fact that I'm STILL pregnant and STILL not sleeping or walking normally or able to turn over or eat without awful heartburn, I'm envisioning my little boy getting cuter and fatter, yes, but also getting his lungs ready to breathe air, his brain ready to process and develop, and am confident that when these systems are a "go," his adrenal glands & lungs will signal my body and start the process to get him out.  Pretty cool, huh?

As I wait, this quote from Jim Elliott came to mind:  "Let not our longing slay the appetite of our living.”  May my excitement and longing to meet my baby boy not ruin these last precious weeks without him-- of time with just Eowyn, of time to enjoy my husband without the demands of a newborn, of time to grow closer to the One who ordains all my days!


Anonymous said...

we were definitely separated at birth! haha!


Glen and Bethany said...

I loved your post and am praying for you. I knew I wanted to wait for Daniel (he was 45 min. shy of 42 weeks), but I was surprised that it was a super emotional time, especially when he missed Christmas - he was "due" on the 14th. All I kept hearing at the doctor's were the potential health risks of being "postdue," so all this info is really encouraging to me. Thanks for your post!