5 Things Everyone Should Know about Late Pregnancy

This one is dedicated to my sister and all the other women out there at the end of their pregnancies. She is done, she feels like the baby is ready and why doesn’t it come already! She feels like 40 weeks is too far away, even though is a matter of only a few weeks now. And even though she already knows all of this, here are a few good reminders about those last few weeks when you feel like you can’t wait one single second longer to meet that baby!

1. Baby is getting ready too. Around 37 weeks the baby may begin to turn and the head starts to descend into the mother’s pelvis. This makes many expecting Moms feel like baby is ready to come now! But, this can happen 3 to 4 weeks before baby actually comes.

2. Baby’s lungs & liver are still developing.  Lungs are one of the very last organs to mature. This is because the lungs are not necessary in the womb, although to get ready for breathing, the lungs do “inhale” amniotic fluid. The lungs are the only organ that develop throughout the entire prenatal period and even after birth (well besides the brain, of course). The saccular phase of lung development is complete by about 37 weeks and generally lungs are considered “mature” at this point. However, the alveolar phase of lung development is just beginning in the last few weeks of pregnancy and will continue after birth. Babies born with saccular lung “maturity” at 36 to 38 weeks gestation had 2.5 times more likely chance for complications than babies born 39 weeks or later.  Problems like respiratory distress, jaundice, and low blood sugar progressively increase in likelihood the earlier the baby is born. The liver is also still developing the ability to eliminate toxins, like bilirubin, which is why there is a greater risk of jaundice in babies born prior to 39/40 weeks.

3. Baby’s brain is still developing. Although we don’t completely understand why, babies born even one or two weeks earlier than full term (40 weeks) babies show worse performance on cognitive tests. Babies born at 37 or 38 weeks showed lower scores on math and reading tests in the 3rd grade than children born at 39 or 40 weeks.  We don’t know why and this isn’t cause and effect, although it is an intriguing finding.

4. Baby develops needed fat insulation in the last week or two. Between 35 weeks and 40 weeks the amount of fat on the fetus doubles. This layer of fat provides the baby with optimal thermal regulation making them more comfortable overall.

5. But what if my baby is born early? Well, take heart… all of the above, for the most part, are based on large group studies based on AVERAGE gestational ages. A recent study showed that the length of pregnancy can naturally vary by up to 5 weeks! This study used a new technique to pinpoint ovulation and implantation meaning that their calculations were based on a true starting point of pregnancy. They found that about 70% of women deliver within 10 days of their due date. This probably isn’t so surprising, but it is the first study I know of to show it. Most experts agree, that if a baby is born “early” without any intervention then they are ready to be here. Most likely, all the development that needed to happen has, including everything listed above.

So, take heart Mamas! That baby is coming— it may seem like forever, but there is important work yet to be done. And if your baby comes early naturally or not (there are many reasons it’s better to deliver early), this post isn’t intended to make you lose hope. There is a whole field of research dedicated to helping premature and early term babies catch up. My favorite series of studies for preemies is the lifelong work of Tiffany Field, who started her research because she had a premature baby herself.  Ask the prenatal nurses about preemie massage or find a certified therapist here. In most cases, preemies or early term babies have “caught up” cognitively to same-age peers by the first grade. This post isn’t meant to convince anyone to delay birth if there is a medical reason, it is just a reminder of all the things happening developmentally those last few LONG WEEKS!