Pregnancy Week 8: Baby's Development, Mom's Symptoms, and Care Tips

From embryo to fetus Week 8 — your baby's heart beats twice as fast as yours, you may feel nauseous all day. This is when everything starts feeling real.

At week 8 of pregnancy, your baby officially graduates from "embryo" to "fetus". Major organs are forming rapidly, and most moms start to notice real pregnancy symptoms — morning sickness chief among them.

This article draws on guidance from NHS [1], ACOG [2], WHO [3], and the Royal Thai College of Obstetricians and Gynaecologists [5].

Your baby at week 8

Your baby is about 16 millimeters long — roughly the size of a raspberry. Officially called a "fetus" from this week onwards.

Organs and structures developing now:

• Heart beats in 4 distinct chambers at 150–170 bpm — about twice your own heart rate
• Arms and legs lengthen, with arms growing slightly faster
• Fingers and toes are forming but still webbed together
• Face — eyes, nose, and lips are increasingly distinct
• Nervous system — brain is developing rapidly
• Placenta — extending villi into the uterine wall to deliver oxygen and nutrients
• Your uterus is now the size of a lemon

Symptoms you may feel

Morning sickness

The most common first-trimester symptom. According to ACOG [2], about 75% of pregnant women experience nausea during the first trimester, with or without vomiting.

Key points:

• Symptoms typically peak around week 9 and ease in the second trimester
• Despite the name, it can happen any time of day
• Treating early helps prevent severe escalation

Other common symptoms

• Unusual fatigue from rising progesterone
• Tender, swollen breasts as glands prepare for lactation
• Frequent urination as hCG stimulates the kidneys
• Mood swings from hormonal shifts
• Heightened smell sensitivity — favorite foods may now make you queasy

Self-care recommendations

Key nutrients

Per WHO Antenatal Care guidance (2016) [3]:

• Folic acid — at least 400 mcg/day to reduce the risk of neural tube defects
• Iron — to prevent anemia; prenatal vitamins typically cover this
• Varied diet — vegetables, fruits, protein, complex carbs
• Water — at least 8 glasses a day

Foods and drinks to avoid

• Alcohol — at any amount, in any form
• Raw meat and fish — risk of Listeria, Salmonella, parasites
• High-mercury fish — shark, swordfish, yellowfin tuna
• Unpasteurized cheese — Listeria risk
• Caffeine — limit to under 200 mg/day (about 1 coffee)
• Liver and liver products — high vitamin A can be toxic at high doses

Coping with morning sickness

Per ACOG Practice Bulletin No. 189 [4]:

• Small frequent meals — avoid an empty or overly full stomach
• Avoid trigger smells
• Sip water or ginger tea between meals, not with them
• Ginger has clinical evidence for easing nausea
• Vitamin B6 (pyridoxine) may help — talk to your doctor first
• Easily digested foods — crackers, congee, fruit

For severe symptoms, ACOG recommends doxylamine + vitamin B6 as a safe, effective first-line treatment.

When to start prenatal care

WHO [3] recommends a first prenatal visit before 12 weeks and at least 8 contacts across the pregnancy — 1 in the first trimester, 2 in the second, and 5 in the third.

What happens at the first visit

• Ultrasound — confirms gestational age, number of babies, fetal heartbeat, and pregnancy location
• Blood work — blood type, Rh factor, CBC, glucose
• Infectious disease screening — HIV, syphilis, hepatitis B, rubella immunity
• Urinalysis — glucose, protein, infection
• Nutritional assessment — weight, height, BMI
• Risk consultation — family history, chronic conditions, medications

Prenatal care coverage in Thailand

Free prenatal care under public health coverage:

• 30-baht (Universal Coverage) scheme via NHSO
• Social Security for insured workers
• Civil Service for government employees and dependents

When to seek care immediately

Contact your doctor or go to a hospital right away if you experience:

• Vaginal bleeding more than light spotting
• Severe abdominal pain, especially one-sided — possible ectopic pregnancy
• Severe nausea and vomiting that prevents fluid intake; weight loss

  5% of pre-pregnancy weight may indicate Hyperemesis Gravidarum

• High fever > 38.5°C (101.3°F) or persistent over several days
• Severe headache, blurred vision, facial or leg swelling — possible early signs of pre-eclampsia

Hyperemesis Gravidarum affects about 0.3–3% of pregnancies and typically requires hospital treatment.

Summary

Week 8 is a pivotal stage — major organs are forming, and you'll likely notice real pregnancy symptoms.

Care principles for this week:

1. Schedule your first prenatal visit before week 12 per WHO guidance
2. Take folic acid at least 400 mcg/day
3. Avoid alcohol, raw meat, raw fish, and high-mercury fish
4. Manage morning sickness with small frequent meals, ginger, and rest
5. Watch for warning signs — bleeding, severe pain, severe vomiting

If anything worries you, don't hesitate to call your provider. There are no small questions when it comes to caring for your pregnancy.