Chapter 31: Pregnancy

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Welcome to this deep dive.

If you're a nursing student listening to this, you already know that your textbooks can be incredibly dense.

Oh, absolutely.

You're just constantly bombarded with these chapters full of complex terminology and changing physiological baselines and high stakes clinical skills.

So today, our goal is to cut through all that noise.

Right.

We're cutting right to the chase.

Exactly.

We are going straight to the core of Chapter 31 on Pregnancy from your textbook, Physical Examination and Health Assessment, 9th edition.

We want to show you exactly how this material actually applies when you are standing right at the bedside.

That is the perfect way to look at it.

Our mission today is to help you master the central assessment focus of this chapter in the exact order it appears in the text.

We're going to build your knowledge logically.

Step by step.

Exactly.

The foundational physiology you learn will directly support your interview skills.

Those interview skills will guide your health history.

Your history informs your physical exam and ultimately those hands -on exam findings are what drive your clinical interpretation and, you know, keep your patients safe.

Okay.

Let's unpack this starting right at the very beginning with the foundational structure and function because it's wild how much happens biologically before patient even feels that first little flutter of fetal movement.

It really is magical biology.

It all kicks off when the fertilized ovum called the blastocyst enters the uterus.

These specialized cells don't just sit there.

They immediately start producing human chorionic gonadotropin or HCG.

And that HCG is a critical messenger.

It essentially yells down to the corpus luteum and the ovary to keep making progesterone.

And progesterone is the heavy lifter that supports the pregnancy for those incredibly vulnerable first few weeks.

Right.

It's holding down the fort until the placenta is fully formed and ready to take over the job.

Precisely.

At about seven weeks, the placenta starts producing its own progesterone.

And by 10 weeks, it has taken over completely.

You can think of the placenta as this massive temporary endocrine organ.

Yeah.

The progesterone it pumps out maintains the endometrium around the fetus.

And crucially, it keeps the uterus relaxed and quiescent so it doesn't start contracting too early.

Which would be disastrous.

Right.

It also increases the alveoli in the breasts.

Meanwhile, estrogen is running a parallel track.

It's stimulating duct formation in the breasts, increasing the sheer weight of the uterus and building up cellular receptors that are going to be absolutely vital later on for birth.

That makes so much sense as to why early pregnancy is so systemically exhausting for the patient.

Now, before we get into the physical changes trimester by trimester, we need to talk about the terminology.

The alphabet soup.

Yes.

Because when you open a patient's chart, you're going to see a string of letters and numbers that honestly looks like a Wi -Fi password.

It's usually something like G5, P4, T3, PT0, A2, L3.

It does look like a random code, but it's actually a brilliantly efficient shorthand.

In five seconds, that code tells you the patient's entire obstetric life story before you even walk into the room.

Let's decode that exact example from the text for you.

The G stands for gravita, which is the total number of pregnancies, regardless of outcome.

In this case, five.

The P is para, the number of deliveries past 20 weeks.

Here, that's four.

And then it breaks down further.

T is for term deliveries, those reaching 37 weeks or more.

PT is preterm deliveries.

A stands for abortions, which is an umbrella clinical term that includes miscarriages, therapeutic or voluntary terminations.

And finally, L stands for living children.

Exactly.

So someone who is pregnant for the very first time is a prima gravita, and someone who has been pregnant before is a multigravita.

Knowing the history is the foundation, but then you have to track the physical changes of their current pregnancy.

Let's walk through those three trimesters head to toe.

In the first trimester, the textbook categorizes the signs of pregnancy into three distinct buckets.

First, presumptive signs.

These are what the patient actually feels and reports to you.

Things like amenorrhea, nausea, relentless fatigue, and breast tenderness.

The classic symptoms.

Right.

Then you have probable signs.

These are things you, the examiner, can objectively detect, like an enlarged, softening uterus.

Finally, there are positive signs, which provide direct, undeniable evidence of a fetus.

The most obvious positive sign being the fetal heartbeat.

And you can actually pick up those fetal heart tones, or FHTs, with a Doppler ultrasound between 9 and 12 weeks.

But something else happens in that first trimester that I think surprises a lot of people.

The patient's blood pressure actually drops.

It does, and it's a vital physiological adaptation.

The falling peripheral vascular resistance causes their blood pressure to dip lower than their pre -pregnancy baseline, and that drop actually becomes most pronounced in the second trimester, right around 20 weeks.

That is exactly why your patient might complain of feeling dizzy or faint if they stand up too quickly.

Precisely.

So if they complain of dizziness, you know the physiology behind it.

But the second trimester brings some relief, too.

The intense nausea usually improves.

And around 18 to 20 weeks, they get to experience quickening, which is that very first sensation of fetal movement.

Though if they are a multigravida, they might recognize that feeling a couple of weeks earlier.

Because they felt it before.

Right.

The second trimester is also when you'll start seeing significant skin and eukosal changes.

You might assess the linea nigra, which is a dark, pigmented midline running down the abdomen, or stria gravidarum, the classic stretch marks.

And you have to check their mouth, right?

Yes.

You absolutely need to check their mouth.

Because of increased cutaneous blood flow and circulating hormones,

the gums might hypertrophy and bleed really easily.

It's a benign condition known as epulis of pregnancy.

And internally, progesterone alters the tone of the esophageal sphincter, which is why they are suddenly dealing with wicked heartburn.

It relaxes everything.

And then we move into the third trimester.

This is where the cardiovascular adaptation is just mind -blowing.

The patient's blood volume increases rapidly and peaks in the pregnancy levels.

Almost half again as much blood.

It is a massive physiological feat.

And what's fascinating here is how the heart adapts to pumping that much extra fluid.

Because of that immense volume, cardiac output, stroke volume, and heart rate all increase.

Consequently, you can hear a functional systolic heart murmur.

Just a normal functional murmur.

Yeah.

Usually a grade two out of six or less.

And you hear this in more than 95 % of pregnant patients.

No wonder they have a murmur.

And mechanically, things are shifting drastically, too.

The growing uterus pushes the diaphragm up, displacing the lungs, which easily causes shortness of breath.

And their center of balance shifts forward, causing a progressive lordosis, that inward curvature of the lower spine, which leads to terrible backaches.

You might even assess for corporal tunnel syndrome, right?

Yes.

As their shoulders slump forward and their breasts become heavier, it can compress the median nerve in the arms.

And of course, the sheer weight of the uterus impedes venous return from the legs, causing lower extremity edema, varicosities, and hemorrhoids.

To manage all these sweeping changes clinically, you need to know exactly where the patient is on their timeline.

This is where you calculate the expected date of delivery, or EDD, using Negsley's rule.

It's a very specific formula.

You take the first day of their last menstrual period, add seven days, and then subtract three watts.

That formula gives you the due date, which acts as the anchor for the entire pregnancy.

And that leads us perfectly into the second major focus of the chapter developmental competence, genetics, and environment.

Because the biological changes we just discussed don't happen in a vacuum.

No, they don't.

Who the patient is and the environment they live in drastically changes the risk profile of the pregnancy.

Let's talk about age demographics first.

The text points out that teen pregnancies in the U .S.

still occur at a higher rate than in other industrialized nations, and the racial and socioeconomic disparities are stark.

Native American, Alaska Native, Black, and Hispanic teens experience birth rates where they're twice as high as their white counterparts.

These pregnancies carry severe medical risks like toxemia and low birth weight, but they are also compounded by huge psychosocial risks and a downward cycle of poverty.

On the completely opposite end of the spectrum, we are seeing a major demographic shift of people delaying childbearing.

That means you will see many more pregnancies in patients over 35, which is clinically termed Advanced Maternal Age, or AMA.

While these patients are often more financially and emotionally prepared, they face distinct biological risks.

The risk for chromosomal anomalies like Down syndrome increases exponentially shifting from one in 1 ,527 at age 20 to one in 356 at age 35, all the way to one in 23 at age 45.

That's a huge jump.

It is.

They also face higher baseline rates of chronic conditions like hypertension, which severely increases the risk of placental abruption and preeclampsia.

So for an AMA patient, genetic screening is a major conversation.

As a nurse, you have to know the timelines for these options.

Chorionic valley sampling, or CVS, can be done between 11 and 13 weeks.

Amniocentesis is an option a bit later, between 15 and 20 weeks.

But there are also non -invasive options now, like free cell DNA testing.

Right.

How does that work?

That has revolutionized screening.

A simple blood draw from the pregnant person can actually isolate and test the circulating fetal DNA for chromosomal abnormalities, entirely avoiding the slight miscarriage risks associated with CVS or amnio.

Genetics and environment also fiercely intersect when it comes to obesity.

The text emphasizes that obesity and gestational diabetes mellitus, or GDM, disproportionately affect certain racial and ethnic groups.

And GDM raises the immediate risk of preeclampsia.

But what's really striking is the long -term impact.

Patients with GDM have a 10 times higher risk of developing type 2 diabetes later in life, along with significantly increased cardiovascular risk.

The textbook also highlights a very important, historically marginalized population you will absolutely care for transgender patients.

There are an estimated 1 .4 million transgender people in the U .S.

As a nurse, providing culturally and medically competent care here is non -negotiable.

Right, because not all gender -confirming care makes pregnancy impossible.

Transgender men who pause their testosterone therapy can successfully conceive and carry a child.

And that pause is critical because testosterone is highly teratogenic to a developing fetus.

And postpartum.

Postpartum, depending on their prior surgical history, chest feeding may also be entirely possible.

But the most important clinical intervention you can offer is creating a welcoming, non -discriminatory environment that affirms their gender identity.

Without that safety, patients won't seek the prenatal care they desperately need.

Speaking of safety and honest conversations, we have to address substance use.

Screening for drug, alcohol, and tobacco use is a mandatory part of the initial prenatal visit for everyone.

Everyone.

Tobacco use shoots up the risks for ectopic pregnancy, low birth weight, and sudden infant death syndrome.

And with the widespread legalization of marijuana, usage is up.

We have to clearly educate patients that THC readily crosses the placenta and passes directly into breast milk, increasing the risk for preterm birth and fetal growth restriction.

The opioid epidemic is another grave clinical reality you will face.

A pregnant person using opioids puts the infant at severe risk for neonatal abstinence syndrome, or NAS.

What does that look like in the nursery?

In the nursery, you'll need to recognize those classic withdrawal symptoms in the neonate.

A distinct high -pitched crying, jitteriness,

poor feeding, and extreme irritability.

Wait, so if you have a pregnant patient with an active opioid use disorder, do we just have them stop cold turkey?

How do you manage that safely?

That is a great question, and the answer is absolutely not.

Medically supervised withdrawal is actually not the standard of care.

Okay.

The safest approach is maintenance therapy with methadone or buprenorphine.

Going cold turkey causes severe physiological stress and withdrawal that can be lethal to the fetus.

That makes sense.

Yeah, maintenance therapy provides a steady state, reduces dangerous risk -taking behaviors, and vastly improves the patient's compliance with prenatal care, which ultimately leads to much better neonatal outcomes.

So we have the foundational physiology, we know the background risks.

Now, we are walking into the exam room for Section 3 subjective data.

This is your health history interview.

But we aren't just checking boxes on a form here, are we?

Not at all.

If we connect this to the bigger picture, the subjective questions you ask in this interview are directly preventing catastrophic emergencies in the delivery room months later.

You are hunting for clinical clues.

Let's start with a gynecologic and obstetric history.

You're obviously going to ask if they've had previous C -sections.

But the text says you must specifically determine the type of uterine incision.

Why does the direction of the scar matter so much?

Because a classical or vertical incision on the uterus carries a significantly high risk of uterine rupture during the intense contractions of labor.

If they have a vertical scar, all future deliveries are mandated to be C -sections.

But a horizontal one is different.

Right.

A low transverse or horizontal incision carries a much lower rupture risk and might safely allow for a vaginal birth later.

You also must take this opportunity to offer HIV screening to all pregnant people, without exception, to initiate early treatment and decrease transmission to the fetus.

When moving to the current pregnancy, your job is to normalize common symptoms while keeping a sharp eye out for red flags.

Breast tenderness and fatigue.

Totally normal.

Nausea early on.

Normal.

But any report of abdominal pain or vaginal bleeding must be investigated immediately for ectopic pregnancy, placental abruption, or premature labor.

The medical history and review of systems section is where you catch hidden risks.

You're checking vaccine status, specifically rubella, because contracting rubella in the first trimester is highly teratogenic and causes severe birth defects.

You'll also screen heavily for urinary tract infections.

The hormonal changes and anatomical schists of pregnancy predispose patients to UTIs, but the pregnancy itself might mask the usual burning symptoms.

An undetected, untreated UTI can severely irritate the uterus and trigger preterm labor.

And wait, looking at the review of systems, why are we asking about their teeth?

What does going to the dentist have to do with having a baby?

It seems disconnected, right?

But the vascular changes we talked about cause the gums to bleed, which can lead to severe periodontal disease.

And systemic inflammation from poor dental hygiene is actually strongly linked to an increased risk of preterm delivery.

It's a vital, often overlooked piece of the puzzle.

That is fascinating.

The interview also includes a paramount safety assessment.

You absolutely must ask about intimate partner violence.

Statistically, abuse often escalates during pregnancy.

Because patients rarely volunteer this terrifying information freely, you must systematically ask these questions in a safe, private, non -threatening environment, preferably when their partner is not in the room.

Finally, you wrap up the interview with nutrition.

You're checking their weight gain trajectory and making sure they know to avoid sea fish, high -end mercury, raw eggs, unpasteurized dairy, and deli meats.

This isn't just a diet tip.

It's strict protection against pathogens like listeria, salmonella, and toxoplasmosis that can easily cross the placenta.

So you've got the full history, you know the risks, now you actually have to put your hands on the patient.

Let's talk about what we're looking for when we start section 4 objective data,

the physical examination.

First, preparation.

Have the patient empty their bladder so they're comfortable, save a urine sample for protein and glucose dipping, and get away and BMI.

But when you position the patient on the exam table later in pregnancy, you cannot lay them flat.

You have to elevate their back to a 30 to 45 degree angle.

Why is that angle so critical?

Because if a patient in their third trimester lays completely flat, that heavy fluid -filled uterus will physically compress the descending aorta and the inferior vena cava against their spine.

This abruptly cuts off venous return to the heart, causing severe maternal hypotension and dangerously compromising blood flow to the fetus.

So bed angled up always.

For the general survey and skin exam, you'll be distinguishing between normal hormonal changes and abnormal pathology.

A normal skin change is colasma, often called the mask of pregnancy.

It's a butterfly -shaped brownish pigmentation on the face.

An abnormal finding would be a rash, like P -U -P -P -P, which stands for pruritic urticarial papules and plaques of pregnancy.

That is an intensely itchy red eruption that appears late in pregnancy and requires symptom management.

Moving to the upper body, when examining the breasts, the increased blood flow is so massive that you might actually hear it through your stethoscope.

This is called the mammary souffle.

I've heard it literally sounds like a rushing river of extra blood flow right under your stethoscope.

That's exactly what it sounds like, which is why it is so easily confused with a cardiac murmur.

But remember, as we mentioned earlier, an actual functional heart murmur is also a normal finding during pregnancy due to that 45 % increase in blood volume.

Right.

You also need to check their deep tendon reflexes or DTRs with your reflex hammer.

Normally, these should be a 1 -plus or 2 -plus and equal bilaterally.

But what if you strike the tendon and get a brisk 3 -plus or 4 -plus reflex, especially with clonus, where the foot essentially stutters or beats back at you?

That is a terrifying red flag.

Hyperreflexia and clonus point directly to severe central nervous system irritability, elevated blood pressure, and cerebral edema.

It is a massive warning sign of worsening preeclampsia.

Next is the abdomen.

We measure fundal height using a simple centimeter tape from the pubic symphysis to the top of the uterine fundus.

After 20 weeks, the rule of thumb is that the number of centimeters should equal the weeks of gestation.

If there are 24 wints, you should measure 24 centimeters.

But what if it's way off?

That measurement is your primary bedside growth screening.

If the fundal height lags behind by 2 centimeters or more, it highly suggests Intra -Daughter and Growth Restriction, or IUGR.

The baby isn't growing as expected.

On the flip side, if it measures more than 4 centimeters larger than expected, you might be dealing with multiple fetuses, a massive excess of amniotic fluid, or large uterine myomas.

Any significant discrepancy means you need to get them to an ultrasound.

Now, in the third trimester, you will perform the Leopold maneuvers.

These are four specific, hands -on steps to determine the fetal lie, presentation, attitude, and position.

I always hear nurses say, This literally feels like trying to figure out if you're pressing on a bowling ball or a sack of flour through the patient's skin.

That is the perfect analogy.

Let's break down exactly where your hands go.

First maneuver, you stand facing the patient's head and place your fingertips around the very top of the fundus.

You are trying to figure out what part of the baby is at the top of the uterus.

And what are we feeling for?

The breech, the buttocks, feels like that sack of flour.

Large, firm, but it moves slowly.

The fetal head, however, feels like the bowling ball.

Hard, round, and if you push it lightly, it aggressively bobs back against your fingers, a sensation called balloting.

Second maneuver, you move your hands down to the sides of the uterus.

Here, you're feeling for the long, firm, smooth surface of the fetal back on one side, and the small, bumpy, knobby limbs on the other.

Third maneuver, also known as Pollock's maneuver, you ask the patient to bend their knees slightly.

You grasp the lower abdomen just above the symphysis tubus between your thumb and fingers.

You are trying to feel the presenting part that is heading into the pelvis.

If it feels fixed and doesn't move easily when you wiggle it, that presenting part has officially engaged into the pelvis.

Fourth maneuver, you turn around and face the patient's feet.

You place your palms on either side of the lower abdomen, pointing toward their feet.

You press firmly and move down toward the pelvic inlet.

This confirms engagement and tells you whether the fetal head is tucked in and flexed or extended.

Immediately after those maneuvers, you use your Doppler to auscultate the fetal heart tones directly over the smooth, fetal back you just located.

You're listening for a normal, rapid rate of 110 to 160 beats per minute.

And a pro tip, always keep your fingers on the patient's radial pulse at the exact same time.

That ensures you don't accidentally confuse a fast maternal heart rate with the fetal heart rate.

Great point.

Finally, we reach the pelvic exam.

You'll see several classic, visually distinct vascular signs due to all that engorgement.

Chadwick's sign is the bluish -purplish discoloration of the vaginal wall and cervix.

Goodell's sign is the physical softening of the cervix.

And Hegar's sign is when the enlarged, heavy uterus actually bends forward on its softened isthmus.

While doing the internal exam, you can assess their pelvic muscle tone and take a moment to teach the patient Kegel exercises to prepare that pelvic floor for birth.

To wrap up the objective data gathering, you'll verify all routine labs are ordered.

The initial panel with CBC, HIV, rubella, and blood type.

And you'll make sure they are scheduled for the crucial standard of care fetal anatomy ultrasound, which usually happens right around 18 to 20 weeks.

Here's where it gets really interesting.

Taking all this dense subjective and objective data and actually applying it to real -world patient scenarios and abnormal findings in Section 5 documentation and clinical interpretation.

The textbook grounds this with two excellent case studies.

First, you have R .G., a 27 -year -old at 10 weeks gestation.

Her assessment is wonderfully textbook normal.

A viable intrauterine pregnancy with size equal to dates, totally normal blood pressure, and transient nausea that completely resolves with a few crackers.

But then we have K .A., a 30 -year -old immigrant from Ethiopia at 11 weeks gestation.

Her case is much more complex.

She's a poor historian regarding her past deliveries.

She doesn't drive.

Her primary language is English.

And objectively during the exam, you note she has had a female circumcision as a child.

K .A.'s case perfectly illustrates why comprehensive clinical competence is so vital.

As the nurse, you are navigating a delicate physical assessment, specifically noting that her circumcision does not have infibulated scarring that would complicate birth.

And you're utilizing resources too.

Exactly.

You are simultaneously utilizing a professional interpreter to ensure she truly understands her prenatal testing options, and you're actively referring her to a social worker for transportation assistance.

The physical medical care is completely inseparable from her cultural and social context.

Now let's break down the major abnormal findings the chapter explicitly warns you about.

We have to start with the big one, preeclampsia.

The book defines this as a blood pressure of 140 over 90 or higher, occurring specifically after 20 weeks gestation in a previously normotensive patient.

The classic hallmark signs you will chart are hypertension and proteinuria.

But you have to understand that this is a systemic, highly progressive condition.

You must constantly monitor for subjective signs like severe headaches and visual changes.

Which, as we mentioned with the reflexes, indicate worsening cerebral edema.

Yes.

Or they might complain of right upper quadrant abdominal pain, which indicates the liver is becoming involved in swelling.

And if that liver gets involved, it can rapidly deteriorate into H -E -L -L -P syndrome.

What does that acronym actually mean when you're standing at the bedside watching a patient crash?

It is a terrifying cascade for a nurse to witness.

H -E -L -L -P stands for hemolysis, elevated liver enzymes, and low platelets.

Let's break that down.

Hemolysis means their red blood cells are literally being destroyed.

Elevated liver enzymes mean the liver is acutely failing and sustaining damage.

Right.

And low platelets mean their blood can no longer clot properly.

They are at risk for massive internal bleeding.

It is an ominous, critical clinical picture that can swiftly progress to true eclampsia, which involves generalized, life -threatening seizures.

We also have to be on high alert for postpartum hemorrhage, or PPH.

It remains the leading cause of maternal death.

It's diagnosed as a cumulative blood loss greater than a thousand middle L, or clinical signs of hypovolemic shock.

The main culprits you'll be fighting are a lack of uterine tone, the uterus refusing to clamp down, or severe internal uterine trauma.

You'll also rely heavily on your objective exam to detect a fetal size that is inconsistent with their dates.

If the baby is measuring remarkably large, it could be fetal macrosomia, meaning the infant weighs over 4 ,000 grams.

That is strongly linked to the obesity and gestational diabetes we discussed earlier.

If it measures much too small, you're immediately worrying about inaccurate dating, placental insufficiency, or preterm labor.

Finally, those Leopold maneuvers you mastered might detect malpresentations.

The text visually describes several variations.

A complete breech, a footling breech where a foot is presenting first, a transverse lie where the baby is completely sideways, and a face presentation.

It's important to remember that before 34 weeks, finding any of these positions is generally considered normal because the fetus still has plenty of room to flip around in the fluid.

But after 34 weeks, things are getting tight.

A vertex or head -down presentation is absolutely necessary for a safe vaginal delivery.

Anything else requires immediate clinical planning.

And stepping back from all of this, taking in everything we've covered, this raises a really important question.

We learned that gestational diabetes and preeclampsia significantly increase the risk of type 2 diabetes and cardiovascular disease later in life.

It makes you wonder, is pregnancy essentially acting as a natural albeit intense physiological stress test?

Is it unmasking a person's underlying cardiovascular and metabolic future decades before it would normally present in a primary care clinic?

That is a fascinating thread to pull on, and it completely reframes how we should view prenatal care as a window into lifelong health.

And with that, you have officially made it to the end of Chapter 31.

You are now fully equipped to tackle your clinical rotations,

master your patient interviews, and walk into your exams with total confidence because you know exactly the why behind the what.

You've definitely got this.

Thank you so much for joining us for this session.

From all of us here at The Deep Dive, your ultimate last -minute lecture team.