Pregnancy Week 21: What to Expect
Baby's development, your body's changes, common symptoms, what to eat, and what to do this week.
Baby's development at week 21
Baby's eyebrows are completing. Baby has well-established sleep/wake cycles, though they do not match yours yet — you will likely notice baby kicks more when you are still (lying down at night, watching TV). Baby's swallowing reflex is strong; baby gulps amniotic fluid, which the kidneys process and release back as urine. Bone marrow is fully producing red blood cells. The taste buds are functional, and baby tastes flavors from the foods you eat.
What's happening in your body
Your uterus is now about an inch above the belly button. The bump is very prominent. You may notice Braxton Hicks contractions starting — mild, irregular tightening of the uterus that lasts 20-30 seconds and goes away. They are practice contractions, not labor. Possible mild back pain as your center of gravity shifts. Possible stretch marks appearing.
Common symptoms at week 21
Stretchy belly skin (sometimes with stretch marks). Possible back pain. Braxton Hicks contractions (irregular, painless tightening). Strong fetal movements. Possible swollen feet or ankles. Possible vivid dreams. Increased appetite. Possible heartburn.
When to call your provider
Regular contractions (every 5-10 minutes, painful, intensifying) before week 37 — call provider, this could be preterm labor. Severe persistent headache, vision changes, sudden swelling. Bleeding or fluid leakage. Severe abdominal pain.
How to feel better this week
Look into childbirth classes — they often run 4-6 weeks and are best done between weeks 28-32, which means signing up soon. Continue Kegels. Sleep on your side. Stay hydrated. Walk daily. Practice deep breathing or meditation; these come in handy during labor. Apply lotion to the belly for itching.
Nutrition focus for week 21
Continue iron, calcium, protein, healthy fats, fiber. Add foods with vitamin K (leafy greens) and zinc (pumpkin seeds, beef) for baby's immune system. Try to eat diverse flavors — baby tastes them through amniotic fluid, and research suggests this may shape food acceptance later.
For your partner
Sign up for childbirth classes together. Look into infant CPR classes too — usually offered separately and very worth it.
This week's to-do
Sign up for childbirth class. Look into infant CPR class.
Is this normal?
Braxton Hicks contractions feel like your uterus is tightening (you can feel a hard, ball-like belly). They are random, painless, and stop when you change position. Real labor is regular, intensifies, and does not stop. By the third trimester you will tell them apart easily.
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