The third trimester is a mix of excitement and anxiety. You're so close to meeting your baby, but your body is working overtime. Most discomforts are normal—the backaches, the heartburn, the waddling. But some symptoms are not just inconveniences; they're red flags signaling potential complications that need immediate medical attention. Missing these signs can have serious consequences. I've seen it in my years as a childbirth educator—patients who brushed off a "weird feeling" only to end up in emergency care. Let's cut through the noise and focus on what truly matters.
What You'll Find Inside
Why Third Trimester Red Flags Matter More Than You Think
By the third trimester, your baby is nearly fully developed, but the placenta and your body are under immense strain. Conditions like preeclampsia, placental abruption, or intrauterine growth restriction often manifest now. The American College of Obstetricians and Gynecologists (ACOG) emphasizes that timely intervention can prevent severe outcomes. Think of it this way: your body is giving you a heads-up. Ignoring it is like ignoring a check-engine light in your car during a long road trip. Not smart.
I remember a client, Sarah, who at 34 weeks mentioned her hands felt puffy. She thought it was just water retention. Turns out, it was an early sign of preeclampsia. We caught it early because she spoke up. That's the key—speaking up.
Key Red Flags You Should Never Ignore
These aren't just items on a list; they're specific symptoms that demand action. Let's break them down.
1. Vaginal Bleeding or Fluid Leakage
Any bleeding in the third trimester is a big deal. Spotting might be from cervical changes, but heavy bleeding could indicate placental abruption or placenta previa. Similarly, a sudden gush or constant trickle of fluid might mean your water has broken prematurely, increasing infection risk. Don't wait to see if it stops. Call your provider immediately.
2. Severe or Persistent Headache
A headache that won't quit with rest or acetaminophen, especially if it's accompanied by vision changes (like seeing spots or blurriness), dizziness, or upper abdominal pain, is a classic sign of preeclampsia. This condition affects blood pressure and organ function. I've had patients say, "It's just a migraine," but migraines in pregnancy can mask preeclampsia. Always get it checked.
3. Decreased Fetal Movement
Your baby's movement patterns are a direct window into their well-being. A noticeable slowdown isn't normal. Many women worry they're overreacting, but here's a rule I give: if your active baby suddenly becomes quiet for several hours, don't second-guess. Do a kick count. Fewer than 10 movements in two hours means call your doctor. Studies cited by the Centers for Disease Control and Prevention (CDC) link reduced movement to fetal distress.
4. Signs of Preeclampsia Beyond Headache
Preeclampsia can be sneaky. Watch for:
- Sudden swelling in hands, face, or feet—not the gradual ankle swelling from standing.
- Upper abdominal pain, often under the ribs on the right side, which can indicate liver involvement.
- Nausea or vomiting late in pregnancy, especially if sudden.
These symptoms together are a red alert.
5. Contractions That Feel Different
Braxton Hicks contractions are normal, but real labor contractions before 37 weeks are a red flag for preterm labor. How to tell? Real contractions get longer, stronger, and closer together over time. If you have more than four contractions in an hour, or any rhythmic tightening with pelvic pressure, contact your healthcare team. Preterm birth is a leading cause of neonatal complications.
Quick Reference Table: Third Trimester Red Flags and Immediate Actions
| Symptom | Possible Cause | What to Do Immediately |
|---|---|---|
| Vaginal bleeding (more than spotting) | Placental abruption, previa | Call provider or go to ER; lie on left side if heavy |
| Severe headache with vision changes | Preeclampsia | Call provider; monitor blood pressure if possible |
| Decreased fetal movement | Fetal distress, cord issues | Do kick count; if low, call provider immediately |
| Sudden swelling in face/hands | Preeclampsia | Contact provider; avoid salty foods |
| Regular contractions before 37 weeks | Preterm labor | Time contractions; call provider if pattern persists |
| Fluid leakage from vagina | Premature rupture of membranes | Note color/amount; call provider; avoid tampons |
What to Do When You Spot a Red Flag: A Step-by-Step Guide
Panicking doesn't help. Here's a practical approach.
Step 1: Pause and Assess. Note the symptom's specifics—when it started, intensity, any triggers. For example, with decreased movement, lie down in a quiet room and focus.
Step 2: Don't Google Yourself Into a Frenzy. I've seen women waste precious hours scrolling forums. Trust your instinct. If something feels off, it probably is.
Step 3: Contact Your Healthcare Provider. Call their emergency line. Be direct: "I'm 32 weeks pregnant and experiencing X symptom." Describe it clearly. They might ask you to come in for monitoring.
Step 4: Prepare to Go In. Have your hospital bag ready, grab your insurance card, and if alone, consider calling a friend or partner. For symptoms like bleeding or severe pain, don't drive yourself.
Step 5: Follow Up. Even if symptoms subside, update your provider. Conditions like preeclampsia can fluctuate.
I coached a mom who felt intense itching all over at 36 weeks. She thought it was dry skin. After urging, she called her OB, who diagnosed intrahepatic cholestasis—a liver condition that increases stillbirth risk. Early treatment saved her baby. That itching was a silent red flag.
Common Mistakes and Expert Insights From the Front Lines
After a decade in this field, I've noticed patterns. Here are subtle errors even savvy moms make.
Mistake 1: Chalking Everything Up to "Normal Pregnancy." Yes, discomfort is common, but new or severe symptoms aren't. A headache that's "the worst of your life" isn't normal. Swelling that pits (leaves a dent when pressed) isn't normal. Distinguish between chronic annoyances and acute changes.
Mistake 2: Waiting Until Your Next Appointment. Appointments are weeks apart. Red flags can't wait. I recall a patient who noticed reduced movement on a Friday and decided to wait until her Monday appointment. By Sunday, she was in labor with a distressed baby. Always err on the side of caution.
Mistake 3: Not Tracking Patterns. Keep a simple log of baby's movements, your blood pressure if monitored, and any unusual feelings. Apps can help, but a notebook works. Patterns matter more than one-off events.
Expert Insight: Many women underestimate the role of intuition. Your body knows. If you feel a sense of dread or "something isn't right," don't dismiss it. Medical professionals, according to ACOG guidelines, take maternal concern seriously. Speak up—you're the expert on your own pregnancy.
Your Burning Questions Answered
Navigating the third trimester is about balance—enjoying the final stretch while staying vigilant. Red flags are rare, but knowing them empowers you. Trust your instincts, communicate with your care team, and don't hesitate to seek help. Your health and your baby's well-being are worth that extra call. For more authoritative information, refer to resources from the American College of Obstetricians and Gynecologists (ACOG) or the CDC's pregnancy pages. Stay informed, stay safe.