What is morning sickness and when does it start?

Bottom lineMorning sickness is the nausea and vomiting of early pregnancy that can occur any time of day, usually starting around week 6, peaking weeks 9 to 10, and easing by weeks 12 to 16; it's driven by rising hCG and estrogen and affects up to 7 in 10 pregnant people. Small frequent bland meals, ginger, hydration, and vitamin B6 help, but severe persistent vomiting (hyperemesis gravidarum) that prevents keeping fluids down needs medical care.

Morning sickness is the nausea and vomiting of early pregnancy. Despite the name, it can happen any time of day. It usually starts around week 6, peaks around weeks 9 to 10, and eases by weeks 12 to 16 for most people.

Why it happens

It's linked to the rapid rise of pregnancy hormones, especially hCG and estrogen. The exact mechanism isn't fully understood, but it's very common, affecting up to 7 in 10 pregnant people.

What helps

• Eat small, frequent meals and avoid an empty stomach
• Bland, dry foods (crackers) - especially before getting up
• Ginger (tea, sweets, or supplements) has good evidence
• Stay hydrated with small sips
• Avoid triggers like strong smells and greasy food
• Vitamin B6 and, if needed, anti-nausea medication from a clinician

When it's more serious

Hyperemesis gravidarum is severe, persistent vomiting that prevents keeping food or fluids down and can cause dehydration and weight loss. It needs medical treatment.

When to see a doctor

• Can't keep fluids down for 24 hours
• Weight loss, dizziness, or very dark urine (dehydration)
• Vomiting with fever or pain

Mild morning sickness is normal and even associated with healthy pregnancy; severe vomiting is not something to tough out.

Read our healthy pregnancy guide and track symptoms with the Pregnancy Week Calculator.

Femora helps you log symptoms week by week to share with your clinician.