Week 18: Hearing Your Voice
Your baby's ears are now well-developed and they're actively listening! They may startle at loud sounds. Yawning, hiccuping, and stretching are common baby activities.
Medically reviewed by Samantha L. Fox, RN, BSN, MSN
Nursing Informaticist · United States Navy Nurse Corps · Last reviewed
Your baby is the size of a...
🫑 Bell Pepper!
👶 Baby Development
- ✓Ears are in final position and hearing is improving
- ✓Baby may react to loud sounds
- ✓Yawning, hiccuping, and stretching regularly
- ✓Myelin is forming around nerves (insulation for signals)
- ✓If female, the uterus and fallopian tubes are formed
- ✓If male, genitals may be visible on ultrasound
💊 Common Symptoms
- •Clear baby kicks and movements (quickening)
- •Lower back pain
- •Leg cramps, especially at night
- •Dizziness when changing positions
- •Increased blood volume (40-50% more than pre-pregnancy)
- •Swollen feet and ankles
🩺Clinical Context — From a Nurse's View
Week 18 is when the anatomy scan typically happens (range: 18-22 weeks per ACOG 2016). It's a detailed 30-60 minute ultrasound checking organ-by-organ structure, placental location, amniotic fluid, fetal growth, and cervical length. Anterior placenta — placenta on the front wall of the uterus — is a normal variant, but it cushions fetal movements so you'll feel kicks later and softer than someone with a posterior placenta. Low-lying placenta or placenta previa (covering the cervix) is identified now and almost always migrates upward by the third trimester as the uterus grows. About 1 in 200 pregnancies has true previa at term and requires C-section delivery. The scan can usually identify fetal sex if you want to know — accuracy is around 95-99% at this gestational age. By now you should be feeling some movement most days; if you've never felt anything, mention it at the scan visit.
Written by Samantha L. Fox, RN, BSN, MSN — Emergency Department nurse, US Navy Nurse Corps officer.
🚨 When to Call (or Go to the ER)
- !Vaginal bleeding — call
- !Severe headache with visual changes, swelling of face and hands — call (early preeclampsia screen)
- !Decreased movement once you've established a baseline — call
- !Severe pelvic pain — call
✅ Normal — Even If It Feels Worrying
- ✓Strong daily flutters and kicks
- ✓Lower back pain
- ✓Leg cramps at night
- ✓Sleep disruption from positioning
✅ To-Do This Week
- Prepare for your anatomy scan ultrasound
- Decide if you want to find out baby's sex
- Start sleeping on your left side for optimal blood flow
- Elevate your feet when sitting to reduce swelling
- Eat bananas and potassium-rich foods for leg cramps
- Consider a maternity support belt for back pain
🩺 Questions for Your Doctor
- ?When exactly is the anatomy scan?
- ?Should we find out the sex?
- ?Is my blood pressure stable?
- ?Are leg cramps a sign of a deficiency?
- ?Is swelling in my feet and ankles normal?
- ?How is the baby's position?
📚 References
- [1]ACOG Practice Bulletin No. 175: Ultrasound in Pregnancy. Obstet Gynecol. 2016;128(6):e241-e256.
- [2]ACOG Practice Bulletin No. 222: Gestational Hypertension and Preeclampsia. Obstet Gynecol. 2020;135(6):e237-e260.
Editorial review: Samantha L. Fox, RN, BSN, MSN. Last reviewed: see footer.
Your baby is the size of a...