First Trimester Symptoms You Shouldn’t Ignore (OB-GYN Advice)

The first trimester can feel like a rollercoaster. You’re excited. You’re nervous. Your body is changing fast and sometimes in ways you didn’t expect.

Most of the time, those changes are completely normal. But there are a few symptoms that you should never brush off.

I’m Dr. Bill Chun, an OB-GYN who’s been caring for expectant mothers for over 30 years. I believe in straight talk, not scare tactics. So let’s walk through what’s normal, what’s not, and when it’s time to pick up the phone and call your doctor.

1. Heavy Vaginal Bleeding

Light spotting can be common early in pregnancy, especially around the time your period would’ve been due. But heavy bleeding — anything that soaks a pad, or bleeding with clots should always be evaluated. It can signal a miscarriage or another pregnancy complication that needs attention right away.

2. Severe Abdominal Pain or Cramping

Mild cramping is often just your uterus stretching to make room for baby. But sharp, one-sided pain or severe cramping that doesn’t go away could be a sign of an ectopic pregnancy or another urgent issue. If you feel this type of pain, especially with shoulder pain or dizziness, call your OB immediately.

3. Persistent Severe Nausea and Vomiting

Morning sickness is part of the pregnancy package for many women. But if you can’t keep food or fluids down for more than 24 hours, you could become dehydrated. This condition, called hyperemesis gravidarum, may require IV fluids and medication.
You and your baby both need proper nutrition and hydration.

4. Fever Over 100.4°F (38°C)

A mild fever can happen for lots of reasons, but during pregnancy, high fevers should be taken seriously. A fever over 100.4°F, especially with chills or body aches, could signal an infection that needs treatment. Some infections can be harmful to your developing baby, so it’s always worth calling your provider.

5. Sudden Swelling of the Face, Hands, or Feet

While mild swelling in pregnancy can be normal later on, sudden or severe swelling in the first trimester can be an early sign of preeclampsia or another serious condition. Even though preeclampsia usually develops later, early swelling still deserves a check-in with your doctor.

Trust Your Gut

Here’s my golden rule: If something feels off, call your OB.
You’re not bothering us. You’re not overreacting. Pregnancy is one of the most important journeys of your life, and it’s our job to keep you and your baby safe.

When in Doubt, Reach Out

I’ve seen thousands of women in their first trimester, and I can tell you — the earlier you ask questions, the better. Waiting and worrying only adds stress.
If you experience any of the symptoms above, or you’re just unsure, call your provider and get checked. Peace of mind is worth it.

Next Steps for a Calm, Confident Pregnancy

Early pregnancy can be overwhelming. There’s a lot of advice out there — some helpful, some… not so much.

That’s why I created the Empowering Pregnancy Program — a complete, OB-backed prenatal resource that gives you week-by-week guidance, live group calls with me, and evidence-based answers you can trust.