5 weeks pregnant
At 5 weeks pregnant, your baby is about the size of a sesame seed: under 1 cm long and lighter than 1 g. The neural tube, which becomes the brain and spinal cord, is forming. This is why folic acid matters so much right now.
Your baby at 5 weeks
The neural tube, which becomes the brain and spinal cord, is forming. This is why folic acid matters so much right now.
| Size | About the size of a sesame seed |
|---|---|
| Length | under 1 cm crown to rump |
| Weight | under 1 g |
Your baby is now an embryo about 2 mm long, made of three layers of cells. The outer layer will become the brain, nerves and skin; the middle layer the heart, muscles and bones; and the inner layer the lungs and gut. A simple tube that will become the heart starts to beat this week, though it is usually too small to see on a scan yet.
How far along are you at 5 weeks?
At 5 weeks pregnant you are in the second month of your pregnancy and the first trimester. You have about 35 weeks to go until your due date. Doctors count pregnancy from the first day of your last period, not from conception, so at 5 weeks your baby has been growing for about 3 weeks. Not sure of your dates? Use our due date calculator.
Your body at 5 weeks
You may notice a missed period, tender breasts and tiredness that hits hard. Take folic acid daily and book your first appointment.
Common symptoms at 5 weeks
Every pregnancy is different, and you may have some, all or none of these.
- Nausea. Morning sickness often starts between weeks 4 and 6. Despite the name, it can strike at any time of day.
- A stronger sense of smell. Cooking smells, perfume or petrol may suddenly feel overwhelming.
- Breast changes. Tenderness, tingling and darker skin around the nipples are common.
- Mood swings. Hormone changes can make you feel tearful or irritable for no clear reason.
- Bloating. Progesterone slows digestion, so you may feel full and gassy.
- Feeling very tired. Your body is working hard to build the placenta.
Your checklist for week 5
- Keep taking folic acid every day. It matters most now, while the neural tube is forming.
- Book your first antenatal (booking) appointment for around 8 to 10 weeks.
- Find out your blood group if you don't know it. It affects your care later on.
- If you conceived through IVF, follow your clinic's plan for medicines and your early scan.
- Download or note your local maternity unit's number.
Tip of the week: Foods to avoid from the start
Avoid unpasteurised milk and cheese, raw or runny eggs unless they are pasteurised, and undercooked meat, including pink kebabs and tikka. Skip liver and liver products such as kaleji, because they contain very high levels of vitamin A, which can harm your baby. Our food guide covers common South Asian and Gulf dishes.
For your partner
She may feel exhausted long before anything shows.
- Take over cooking if smells bother her
- Keep the news private until she's ready
- Go with her to the first appointment
When to call your doctor at 5 weeks
Contact your doctor, midwife or maternity unit the same day if you have:
- Bleeding with cramping or one-sided pain.
- Being sick so often that you can't keep any fluids down for 24 hours.
Call your doctor or hospital straight away for bleeding, severe pain, fluid leaking, severe headache or vision changes.
Questions about 5 weeks pregnant
Can you see the baby on a scan at 5 weeks?
Usually only the pregnancy sac, and sometimes the yolk sac, can be seen at 5 weeks. The embryo and its heartbeat normally show up on a vaginal scan from about 6 weeks. If an early scan shows less than expected, it is often just too early, and a repeat scan 7 to 10 days later gives a clearer picture.
Is it normal to have no symptoms at 5 weeks?
Yes. Many women feel completely normal at 5 weeks, and symptoms can come and go. Having few symptoms does not mean something is wrong.
How much folic acid should I take?
Most women need 400 micrograms a day from before conception until 12 weeks. Some women need a higher 5 mg dose prescribed by a doctor, for example if they have diabetes, a BMI of 30 or more, take certain epilepsy medicines or have had a previous pregnancy affected by a neural tube defect.