Chapter 13: Anatomy and Physiology of Pregnancy

Welcome to Last Minute Lecture.

This free chapter overview is designed to help students review and understand key concepts.

These summaries supplement not replaced the original textbook and may not be redistributed or resold.

For complete coverage, always consult the official text.

Imagine a muscle in your body expanding from basically the volume of a shot glass to the size of a massive punch bowl in just a matter of months.

It's honestly the absolute definition of dynamic adaptation.

I mean, we are talking about a complete systemic overhaul of human physiology.

Right.

It's designed to sustain two lives simultaneously.

Sounds like science fiction, but you know, it happens thousands of times a day all over the world.

Exactly.

Every single day.

And if you are joining us for this deep dive, there's a very good chance you are a nursing student.

You're probably prepping for your clinical rotations or maybe staring down a major maternal newborn exam.

Which can be incredibly daunting.

Oh, absolutely.

I know the sheer volume of maternal physiology can feel completely overwhelming.

It's like having to relearn human anatomy from scratch.

It really is.

But take a deep breath.

Our goal today is to walk through this material so that by the end of our time together, you have a rock solid clinical foundation for safe, prioritized nursing practice.

Yeah, we are going to unpack the underlying physiology of pregnancy, focusing on Chapter 13.

We'll look at the expected clinical findings and the abnormal deviations you need to catch immediately.

Because catching those deviations early is everything in practice.

Precisely.

And we'll see how all of this informs your critical nursing priorities.

Now, to set the stage, normal gestation is about 40 minutes or 280 days.

Right.

Divided into three trimesters.

Yes.

And the fundamental principle to keep in mind is that every single maternal adaptation we discuss is a brilliant protective mechanism.

The body is orchestrating these massive shifts to protect the mother's functioning while meeting the enormous metabolic demands of a developing fetus.

So let's unpack this by starting right at the source of all these changes.

The reproductive organs.

Because obviously the body has to physically make room.

I mentioned the punch bowl analogy earlier, but what does that growth actually look like clinically?

The structural transformation of the uterus is staggering.

Before pregnancy, a non -pregnant uterus weighs maybe 40 to 70 grams.

And it holds about 10 milliliters of volume.

10 milliliters.

That's practically nothing.

Right.

But by term, it weighs roughly 1200 grams.

And its capacity expands to 5 liters.

Wow.

5 liters.

Yeah.

And this isn't just stretching.

It's active growth driven early on by high levels of estrogen and progesterone.

So the hormones are literally building new tissue.

Exactly.

These hormones stimulate hyperplasia, which is the production of new muscle fibers.

And they also stimulate hypertrophy, which is the massive enlargement of existing formers.

And as nurses, we can actually track that growth from the outside, right?

We use fundal height to see where the top of the uterus is located in the abdomen.

We do.

The growth provides very specific clinical landmarks.

So at 12 to 14 weeks, the uterus has grown enough that you can finally palpate it just above the symphysis pubis.

Okay.

So just peeking out of the pelvis.

Right.

Then by 20 to 22 weeks, that fundus reaches the level of the patient's umbilicus.

So right at the belly button.

Yep.

And by term, it has grown all the way up to hit the xiphoid process at the bottom of the rib cage.

That sounds so uncomfortable.

It is.

But then, right before birth, a process called lightning occurs.

The fetus descends into the pelvis and the fundal height actually drops back down a bit.

Which I'm sure is a huge relief for breathing.

But that structural pressure has to cause some immediate side effects.

If you have this heavy growing muscle expanding in the pelvis, what happens to the organs right next to it?

Well, that brings us to a classic first trimester symptom.

Around six weeks, pregnant patients experience what we call the HIGAR sign.

HIGAR sign.

What exactly is that?

It's a noticeable softening and compressibility of the lower uterine segment.

Because that lower segment is so soft, the heavy upper part of the uterus actually flexes forward.

Oh, and it rests directly on the bladder.

Exactly.

That physical compression is exactly why patients experience intense urinary frequency early in pregnancy.

That makes total sense.

And as this massive muscle grows, it starts practicing for the main event, right?

Patients might start feeling Braxton Hicks contractions after the fourth month.

Yes, they do.

And those are irregular, they are painless, and most importantly, they do not cause cervical dilation.

But here's where I'd love your clinical insight.

Let's say a patient calls the clinic totally panicked because they're having contractions.

How do we help them distinguish a harmless Braxton Hicks contraction from, you know, dangerous preterm labor?

That scenario requires immediate critical thinking.

The hallmark of Braxton Hicks contractions is that they typically cease with walking or a change in activity.

Oh, okay.

So moving around actually helps.

Right.

And they do not increase in intensity, duration, or frequency.

Preterm labor contractions are the exact opposite.

They will not stop with walking, and they follow a regular progressive pattern.

So the critical nursing teaching here is that if a patient is ever in doubt, they must come in to be evaluated.

Absolutely.

Assuming it's just Braxton Hicks when it's actually preterm labor can lead to a dangerous delay in essential interventions.

Right.

Better safe than sorry.

Let's talk about the sensory milestones, too.

There's this moment called quickening, which is the first time a patient actually feels

It's a very special milestone.

Yeah, it's often described like a gentle flutter.

But it's fascinating because a patient who has been pregnant before a multipara might recognize that flutter as early as 14 to 18 weeks.

While a nullapara, someone pregnant for the first time, might not notice it until 18 weeks or later.

Because they just don't know what they're looking for yet.

Exactly.

And while the patient is feeling those flutters as clinicians, we can also assess the massive increase in maternal blood flow to the uterus, which ramps up tenfold.

Tenfold.

That's incredible.

Yeah.

Sometimes when listening to the abdomen, you can hear a uterine souffle.

This is a rushing sound of maternal blood flowing through the uterine arteries.

And it perfectly synchronizes with the maternal pulse.

Okay, but we have to distinguish that from the funic souffle, right?

Yeah, correct.

The funic souffle is the sound of blood coursing through the umbilical cord, and that sound syncs with the much faster fetal heart rate.

Got it.

Now, obviously, the uterus doesn't operate in isolation.

The cervix and vagina are undergoing their own intense preparations.

They absolutely are.

By the sixth week, the cervix undergoes significant softening, known clinically as the GUDEL sign.

GUDEL sign.

And the tissue changes quite a bit too, doesn't it?

It does.

The cervical tissue becomes highly friable.

Friable meaning easily damaged.

Exactly.

It's incredibly vascular and fragile, which is why a patient might experience slight spotting after a routine vaginal exam or after intercourse.

That's good to know for patient education so they don't panic.

Definitely.

We also see the endocervical cells ramp up mucus production.

They create a thick mucus plug or a perculum, which essentially seals the endocervical canal.

Like a cork in a bottle.

Basically, yeah.

It is a brilliant physical and immunological barrier that stops ascending bacterial infections from reaching the fetus.

And the vaginal mucosa changes visually too, right?

Because of all that increased vascularity.

Yes.

The tissue takes on a violet -blue tint, which is called the Chadwick sign.

You also see a lot of lucaria, which is a normal white mucoid discharge.

But what I find really fascinating is how the body manages the microscopic environment down there.

The vaginal microbiome completely shifts.

It's a perfect example of protective adaptation.

The vaginal environment becomes significantly more acidic due to a huge increase in lactobacillus.

So it's purposely making itself hostile to bad bacteria.

Exactly.

This highly acidic environment is a defense mechanism to prevent harmful bacteria from multiplying and causing an infection that could trigger preterm labor.

But every adaptation has a trade -off, doesn't it?

Unavoidably.

That exact same glycogen -rich, highly acidic environment makes the pregnant patient significantly more vulnerable to yeast infections like candidiasis.

Right.

Rounding out the reproductive changes, we have to look at the breasts.

The changes there happen very early on, driven by estrogen and progesterone.

You'll see the areolae darken and enlarge.

And you'll notice Montgomery tubercles pop up.

Those are the little sebaceous glands on the areola, right?

Yes.

They secrete lubricating and anti -infective substances to protect the nipples for future breastfeeding.

But the real magic is happening internally.

I mean, by the end of the first trimester, the body is already in lactogenesis stage 1.

It's preparing way in advance.

Yeah, it's producing colostrum, that nutrient -dense early milk.

But it holds off on actual lactation until progesterone levels plummet after the baby is born.

And if we think about the incredible amount of energy and fluid required to support all of this, building a placenta, expanding a uterus, producing colostrum, it requires a massive upgrade to the body's internal delivery system.

So the cardiovascular system has to essentially become a supercharged engine.

Exactly.

The numbers on this are wild.

Total blood volume increases by 40 to 45 % over the patient's baseline, peaking around 32 weeks.

And cardiac output increases by 30 to 50 % to move all that extra volume.

Plus, the maternal heart rate naturally jumps about 15 to 20 beats per minute to keep everything flowing.

All of that extra blood is just vital.

It hydrates the rapidly expanding maternal and fetal tissues.

It meets the demands of the highly vascular uterus.

And just as importantly, it provides a massive fluid reserve.

I mean, the body is proactively building up extra blood to compensate for the inevitable blood loss that will occur during childbirth.

It's brilliant planning by the body.

Oh wait, if you pump 45 % more fluid into a closed plumbing system and you increase the pump's output, shouldn't blood pressure absolutely skyrocket?

You would think so, but in a healthy pregnancy it doesn't.

Cystolic pressure stays about the same, and diastolic pressure actually drops slightly until mid -pregnancy before returning to baseline.

How does this system not just blow a valve?

Systemic vascular resistance drops significantly.

Hormones like protestorone, relaxin, and prostaglandins are potent vasodilators.

So they relax the blood vessels.

Yes.

They relax the smooth muscle in the vessels, allowing them to widen and accommodate all that extra volume without raising the pressure.

That makes sense.

But speaking of pressure, we have to talk about how the sheer physical weight of the pregnancy interacts with the cardiovascular system.

This is a crucial area for nursing assessment.

Right, because this brings up a critical nursing intervention regarding positioning.

If a patient lies flat on her back during the second half of pregnancy, that heavy fluid -filled uterus presses directly down on the inferior vena cava.

This creates a dangerous condition known as supine hypotensive syndrome or vena cava syndrome.

Because it's literally squishing the vein.

Exactly.

Compressing that major vein drastically reduces venous return to the heart.

Cardiac output can plummet by as much as 25 to 30 percent.

Wow.

So what happens to the patient?

The patient's systolic blood pressure drops, they experience reflex bradycardia, and they will feel dizzy, faint, and nauseous.

So the intervention here is immediate and non -negotiable.

You must get the patient off their back.

Sideline or lateral positioning instantly relieves that compression and restores normal blood flow.

Okay, here's where it gets really interesting when we look at the lab values for all this extra blood.

Yeah.

Patients often hear they have physiologic anemia of pregnancy, and honestly it sounds terrifying.

It does.

It causes a lot of anxiety.

But I like to think about it like making a pot of soup.

Oh, I like where this is going.

Imagine you're making chicken noodle soup.

You decide to add 30 percent more noodles, which represent our oxygen -carrying red blood cells.

Okay.

But at the same time, you add 50 percent more broth, which is the blood plasma.

When you look in the pot, the soup actually looks thinner and more watered down, even though there are technically more noodles in there than you started with.

I love that analogy because it perfectly illustrates hemodilution.

The plasma volume expands much faster than the red blood cell mass.

So the concentration drops.

Right, because the concentration of red blood cells is diluted, the hemoglobin and hematocrit values drop.

But when do we actually worry about it clinically?

Clinically, a pregnant patient is considered anemic and might need iron supplementation if their hemoglobin falls below 11 grams per deciliter in the first or third trimester, or below 10 .5 in the second trimester.

And we can't discuss the blood without mentioning clotting.

Pregnancy is a hypercoagulable state, right?

Yeah.

The body increases its clotting factors and actually depresses fibrinolytic activity, which is the system that normally breaks down clots.

Yes.

I assume you recognize this as another protective mechanism against bleeding out during delivery.

Yeah, that makes sense.

But it seems dangerous.

It is a mechanism with a severe risk profile.

Because the blood is thicker and more prone to clotting, the patient is at a five - to six -fold increased risk for venous thromboembolism, or VTE.

A six -fold increase?

That's huge.

It is.

This risk remains high throughout pregnancy and the postpartum period, especially if they have a cesarean birth or limited mobility.

Okay, so we have this massive cardiovascular system pumping all this extra fluid, but pumping more blood requires more oxygen.

And building a baby requires an immense amount of nutritional fuel.

Let's look at how the respiratory and gastrointestinal systems adapt to this workload, starting with the lungs.

How does a pregnant patient even take a full breath when the uterus is taking up so much space in the abdomen?

It requires a mechanical shift.

As the uterus pushes upward, the diaphragm is elevated by as much as four centimeters.

Four centimeters is a lot of lost space.

It is.

To compensate for losing that vertical space, the ribcage actually flares outward.

The ligaments of the ribcage relax again thanks to progesterone, and the patient's breathing switches from primarily abdominal breathing to chest breathing.

And even though their respiratory rate stays pretty normal, the actual amount of air they move in and out, the tidal volume increases by about 40%.

They are essentially in a state of chronic mild hyperventilation.

Why does the body force them to over breathe like that?

It's all about gas exchange at the placenta.

By hyperventilating slightly, the mother blows off more carbon dioxide, causing her arterial carbon dioxide levels to drop.

Which creates a slight state of respiratory alkalosis.

Exactly.

This gradient is brilliant because it makes it much easier for carbon dioxide from the fetus to cross the placenta into the mother's blood, while simultaneously making it easier for the mother's oxygen to cross over to the fetus.

The body is just so smart.

But the respiratory tract also deals with capillary engorgement from all that extra blood and hormones, right?

Yes, unfortunately.

That's why pregnant patients get those annoying symptoms like constant nasal stuffiness, changes in their voice, or even epistaxis nosebleeds.

It's not a cold.

It's just vascular swelling.

Now when we look at how the body processes fuel, the gastrointestinal system is perhaps where patients feel the most day -to -day discomfort.

Let's start in the mouth.

Right.

That same vascular engorgement can make the gums spongy and easily prone to bleeding.

You might even see an epilus, which is a red raised nodule on the gums.

And what about the extra saliva?

Patients also frequently report titialism or excessive salivation.

This is often because underlying nausea makes them swallow less frequently.

And the nausea is relentless for many.

I mean, up to 80 % of pregnant people experience nausea and vomiting of pregnancy, or NVP.

It typically peaks between 8 and 12 weeks.

So does a nurse.

How do we know when normal morning sickness crosses the line into something dangerous?

We watch for systemic effects.

If the nausea and vomiting becomes severe enough to cause weight loss, dehydration, or electrolyte imbalances, or if it's accompanied by fever or severe abdominal pain that points toward hyperemesis gravidarum.

Or another underlying pathology.

Right.

That requires immediate medical evaluation and often IV hydration and antiemetics.

Another unique GI quirk is pica, the craving to eat non -food items like ice, clay, or laundry starch.

It's a very important assessment piece.

Yeah.

If a patient mentions they are chewing on ice all day, that is a massive clinical red flag for us to screen them for iron deficiency anemia.

But moving down the digestive tract, we really have to look at the double -edged sword of progesterone.

We established earlier that progesterone is vital because it relaxes the smooth muscle of the uterus, keeping it quiet and preventing premature labor.

The problem is that progesterone is not selective.

It relaxes smooth muscle everywhere in the body.

Everywhere.

So it relaxes the cardiac sphincter at the top of the stomach, which allows stomach acid to splash up into the esophagus.

Hello?

Severe heartburn and reflux.

Exactly.

The stomach itself empties more slowly, and in the intestines, peristalsis becomes sluggish.

So when you combine sluggish bowels with increased water absorption in the colon, you get significant constipation.

Add in the enlarging uterus physically pushing the stomach upward, and pregnant patients also have a much higher incidence of hiatal hernias.

That displacement affects the entire abdominal cavity, doesn't it?

Profoundly.

For instance, as the uterus grows, it pushes the appendix upward and laterally, high and to the right.

It completely moves away from its normal location at McBurney's point.

This anatomical shift is critical to remember, because if a pregnant patient develops appendicitis, their pain will likely be much higher in the abdomen.

Making it incredibly tricky to diagnose.

Processing all this extra metabolic fuel and waste brings us to the body's filtration plant, the urinary system.

The kidneys actually grow in size.

They do.

And again, thanks to hormones and physical pressure, the renal pelvis and the ureters dilate.

That dilation is particularly pronounced on the right side, isn't it?

It is.

The heavy uterus naturally tends to rotate to the right, because the large sigmoid colon takes up space on the left side of the pelvis.

So this right -sided compression slows the flow of urine down the ureter, causing urinary stasis.

And any time urine sits still in the body, it becomes a massive risk factor for bacterial growth.

That is exactly why pregnant patients are so prone to urinary tract infections.

But functionally, the kidneys are working in overdrive.

The glomerular filtration rate, or GFR, increases by 50 % just to handle the combination of maternal and fetal metabolic waste.

Because the kidneys are filtering the blood so much faster and more efficiently, you'll actually see a decrease in normal serum waste products.

Right.

A pregnant patient's blood urea nitrogen, or BUN,

and their serum creatinine levels will be lower than a non -pregnant baseline.

The kidneys are filtering so fast that the two - Okay, so while the kidneys handle the internal waste, the physical strain of carrying this pregnancy shows up externally on the integumentary and musculoskeletal systems.

Why do pregnant patients develop things like the mask of pregnancy, or that dark line down their stomach?

The anterior pituitary gland ramps up the production of melanotropin, which stimulates melanin production.

Oh, so it's a hormonal pigment change.

Yes.

This hyperpigmentation causes melasma, the brownish blotches on the face, and the linea negra, the pigmented line extending up the midline of the abdomen.

You will also see striae gravidarum, or stretch marks, which occur when the underlying connective collagen literally separates under the tension of the growing abdomen.

The surge in estrogen can also cause palmar erythema, leaving the hands blotchy and red.

And many patients experience generalized peritis, or severe itching.

And beneath the skin, the skeleton is being forced to completely realign itself.

I mean, the sheer weight of the abdominal distension pulls the pelvis forward.

To keep from falling straight over, the patient has to compensate by throwing their shoulders back.

They develop lordosis, which is an exaggerated inward curve of their lower lumbar spine.

I always picture it like someone doing a constant, exhausting gymnastics balancing act while wearing a heavy backpack strapped to their front.

That shifting center of gravity is a major hazard.

When you combine that altered balance with the hormonal joint laxity caused by relaxin, the pregnant patient becomes a significant fall risk.

So as a nurse, prioritizing fall prevention education and ensuring safe mobility is essential.

Relaxin is fascinating because it specifically targets the sacroiliac joints and the symphysis pubis, widening them to eventually let a baby pass through the pelvis.

But the side effect is that classic unstable waddling gait, which can be incredibly painful.

We also see muscular strain in the abdomen, like diastasis recta abdominis.

This is where the two halves of the rectus abdominis muscle physically separate at the midline, allowing the abdominal contents to bulge outward.

Wow.

Managing this chaotic symphony of cardiovascular, respiratory, and structural changes requires master control systems to keep everything in check.

This brings us to the neurologic, endocrine, and immune adaptations.

Neurologically, some changes are mechanical.

A lot of patients complain about numbness or burning in their hands, particularly in the third trimester.

This is carpal tunnel syndrome, but it's not from typing too much.

No, not at all.

It's actually caused by the normal peripheral edema of pregnancy physically swelling the tissues and compressing the median nerve beneath the carpal ligament in the wrist.

A far more urgent neurologic symptom to monitor is headaches.

Yes, tension headaches can occur from hormonal shifts, sinus congestion, or just the sheer fatigue of pregnancy.

However, the critical safety alert here is that a persistent or severe headache during pregnancy is a primary red flag for preeclampsia.

It must never be dismissed as just a normal symptom.

It has to be carefully evaluated to rule out dangerous neurological irritability.

The endocrine system is pulling the strings behind the scenes.

Initially, human chorionic gonadotropin, or HCG, is the hero.

It maintains the corpus luteum in the ovary, forcing it to keep pumping out estrogen and progesterone until the placenta is fully formed and can take over hormone production.

The maternal thyroid gland also enlarges and kicks its basal metabolic rate up by as much as 25%.

This is absolutely critical because the fetus does not produce its own thyroid hormones until about 12 weeks.

So until then, it is entirely reliant on maternal thyroxine, or T4, which is vital for the early development of the fetal central nervous system.

And the pancreas is fighting its own battle.

The placenta produces hormones like human chorionic somatomemitropin, which intentionally act as insulin antagonists.

They purposefully create a state of maternal insulin resistance.

The mechanism here is to ensure that plenty of raw glucose remains circulating in the maternal bloodstream so it can be shipped across the placenta to feed the rapidly growing fetus.

Right.

So to counteract this resistance and manage her own blood sugar,

the mother's pancreas has to hypertrophy and drastically increase its insulin production.

Finally, we must rethink the immune system.

A long -standing misconception is that pregnancy requires a state of total maternal immunosuppression.

So the mother's body doesn't reject the foreign DNA of the fetus.

But that isn't accurate, is it?

No, it's not.

It's not suppressed.

It's just dynamically changing its priorities.

It operates in a beautifully choreographed three -stage flux.

Exactly.

The first and early second trimesters are actually a pro -inflammatory state.

This inflammation is necessary to break down tissue and allow the embryo to implant into the uterine wall and establish the placenta.

Then, as the fetus begins its rapid growth in the second trimester, the maternal immune system shifts predominantly to an anti -inflammatory state.

This is the tolerance phase that protects the fetus from being attacked.

And finally, as the body nears term in the third trimester, it reverts back to a pro -inflammatory state.

Because that localized inflammation in the myometrium is actually a required mechanism to help ripen the cervix and initiate the onset of labor contractions.

So we have just walked through this profound biological mechanism, how the heart,

lungs, hormones, and immune system physically adapt to create life.

But practically speaking,

how do we clinically detect and confirm that all this is happening?

Let's finish up by talking about the diagnosis of pregnancy.

The definitive biological marker for pregnancy is the presence of HCG.

It can be detected in the maternal serum or urine as early as seven to eight days before the expected start of the next menstrual cycle.

And early in a healthy pregnancy, HCG levels double approximately every two days.

They hit their peak around 60 to 70 days into the pregnancy, and then they slowly decline to a lower level as the placenta matured and takes over the primary hormone production.

We generally see two main ways to test for this.

Quantitative serum testing is done via a blood draw in the clinic.

It is highly accurate because it measures the exact numerical amount of HCG circulating in the blood.

Then we have the sandwich -type immunoassay testing, which is the foundational science behind over -the -counter home urine pregnancy tests.

The accuracy of those home tests is incredibly reliant on the patient performing them correctly, which requires clear self -management education from the nurse.

We always advise patients to use a first -voided morning urine specimen.

Why?

Because after sleeping all night without drinking water, that first urine is the most highly concentrated, meaning the HCG levels will be easier for the test strip to detect.

We also have to teach them that certain factors can skew the results.

For example, medications like anticonvulsants can occasionally cause false positive results.

While taking diuretics or medications like promethazine can dilute the urine and cause false negatives.

But this brings up a highly common clinical scenario that nursing students will encounter constantly.

Exactly.

Let's say a patient calls the clinic.

They're incredibly anxious.

They missed their period yesterday, so they took a home pregnancy test this morning, and it came back negative.

But they are still experiencing breast tenderness and nausea.

Right.

How do we explain why they might still be pregnant despite the negative test?

The most common error in home testing is simply testing too early.

Oh, of course.

If ovulation happens slightly later than they thought, or if implantation took a few extra days, there simply hasn't been enough time for the HCG levels to rise high enough to meet the detection threshold of that specific urine strip.

So the standard nursing self -management teaching in this scenario is clear if the test is negative.

But your menses still have not started, wait exactly one week, and repeat the test.

It's a simple instruction, but it saves a lot of unnecessary stress.

This has been an incredible journey through maternal anatomy and physiology.

To synthesize everything we've covered,

understanding this foundational physiology directly translates into safe, effective clinical reasoning.

Yes.

When you grasp the baseline shifts of a pregnant body, you can confidently recognize why a You can distinguish between the expected mechanical ache of round ligament tension and the severe dangerous headache of preeclampsia.

Recognizing these expected systemic adaptations is the only way a nurse can quickly and accurately spot the dangerous deviations that require immediate medical intervention.

I want to leave you with a final thought to mull over.

We've talked extensively about how the mother's body adapts to tolerate and nurture the fetus, but what happens after the baby is born?

That's a whole other deep dive.

Right.

How does the body dismantle an entire temporary organ system and reverse these massive cardiovascular and structural changes?

In even more fascinating, research into the immune adaptations we discussed suggests that fetal cells can cross the placenta and remain living inside the mother's body for decades after birth.

It's known as fetal microchimerism, it's truly amazing.

So the next time you care for a pregnant patient complaining about the intense urinary frequency or the heartburn, remember that this isn't just a temporary inconvenience.

The body is performing a miraculous feat of biological engineering,

and the physiological imprint of this experience will quite literally stay with them forever.

A great perspective to keep in mind.

Thanks for joining us on this deep dive.

On behalf of the Last Minute Lecture team, you've got this, and we'll see you next time.