Week 17 is around when some women feel the first movements, though most feel nothing for several weeks yet. Early movements are so faint they are usually mistaken for wind. Your waist starts to go about now, which is the point most women stop being able to hide a pregnancy.
Your body this week
The womb is moving up and out of the pelvis, which makes a bump more obviously a bump. The placenta is growing too — the NHS puts its weight at around 500g by the end of pregnancy.
Stretch marks affect up to eight in ten women, according to the NHS, and they show as pink, red, purple or brown streaks depending on skin colour. They usually appear on the stomach and breasts, sometimes the bottom and thighs, and typically fade to silver after the birth.
Around one in five women feel stressed or anxious during pregnancy. Hormones can make ordinary problems feel unmanageable, and the advice is the same as in the first trimester: tell a midwife or doctor rather than waiting for it to lift.
What you may notice
Tiredness and sleep problems, sore gums, round ligament pains, headaches, nosebleeds, bloating and constipation, indigestion and heartburn, sore breasts, leg cramps, feeling hot, dizziness, swollen hands and feet, urine infections, vaginal infections, and skin and hair changes.
The NHS describes early movements as bubbling, fluttering or rolling, and notes that women often feel them more after meals, when relaxing, or when there is loud music. There is no counting to do at this stage and no pattern to establish yet.
Your baby this week
Around week 17, the figure quoted is about 12cm from head to bottom, which the NHS compares to a pomegranate. It describes a population average and not one pregnancy.
Eyes can move behind closed lids, loud noises get a reaction, and the mouth opens and closes. Fingernails are starting to grow, and fingerprints are forming — unique even in identical twins.
What care usually happens around now
Nothing is routinely scheduled in the UK this week. The anomaly scan is the next fixed point, offered between 18 and 20 weeks in England, so if you have no date yet this is the week to chase it.
If you have not decided where you would like to give birth, this is around the point services expect the conversation to start. Options differ hugely between countries and even between areas.
This week's tip
Do not start counting movements yet — instead, notice when you feel them. Early movements are irregular by nature and counting them at 17 weeks produces anxiety rather than information. What is worth building now is the habit of noticing, because from around 24 weeks a pattern of your own is exactly what matters.
When to see a doctor
Report bleeding, severe pain, a fever, or a headache with vision changes. If movements have started and then clearly change or reduce, contact your maternity service — not an app, and not a chart. Pregnancy warning signs covers the rest.
Seek care now: Contact your local emergency services or go to your nearest emergency department if you have heavy bleeding, severe or one-sided tummy pain, a severe headache with vision changes, sudden swelling of the face or hands, a fever, fluid leaking from the vagina, chest pain, trouble breathing, fainting, or a seizure. Femio cannot assess a pregnancy.
Frequently asked questions
Was that a movement or wind?
Early on, most women genuinely cannot tell, and that is expected. It becomes unmistakable over the next few weeks.
Can I do anything about stretch marks?
Nothing is proven to stop them, and they affect most women. Week 18 covers the anomaly scan, and week 16 covers the appointment behind you.