Week 5of 40
Trimester 1
from 4 full weeks + 0 days to 4 full weeks + 6 days
The fetus
0.2 cm
Size of a sesame seed
- The heart begins to beat — the first heartbeats can sometimes be seen on ultrasound already now.
- The neural tube, which will become the brain and spinal cord, begins to close.
- Small buds that will become arms and legs start to appear.
- The embryo is about 2 mm long.
Your body
Physical changes
- The uterus begins to grow, but it is not visible from the outside yet.
- The breasts may feel swollen and tender.
Common symptoms
- Nausea, sometimes called morning sickness, but it can occur at any time of day.
- Extreme fatigue — the body is working hard to build the placenta.
- Frequent bathroom visits due to increased blood volume.
Emotional changes
- Mood swings are common. Be kind to yourself.
Good to know
- Book your first midwife appointment if you haven't already.
- Rest when you need to — the fatigue is completely normal and will pass.
- Eat small meals frequently if you feel nauseous.
Appointments & check-ups
- Call the midwife clinic to book a registration appointment, which usually takes place in weeks 7-10.
Food & nutrition
If nausea makes it difficult to eat, focus on what you can manage. Not every nutrient needs to be in every meal.
Good to eat
- Small, frequent meals can ease nausea.
- Dry bread or crackers before getting out of bed in the morning.
- Ginger in tea or food can help with nausea.
Be aware of
- Limit caffeine to a maximum of 300 mg per day (about 3 cups of coffee).
Avoid
- Alcohol in any amount.
- Raw fish and raw meat.
Supplements
- Folic acid 400 micrograms daily — especially important now as the neural tube is forming.
- Iron supplements may be needed if you have low iron levels.
Exercise
Continue with your regular exercise, but listen to your body. Fatigue may mean you need to adjust the intensity.
Suggested activities
- Walks in fresh air
- Swimming — gentle and relieving
- Yoga or stretching
Sources
The content on this website is based on information from 1177.se and the Swedish Food Agency. It does not replace professional medical advice. Always contact your midwife or doctor with questions about your pregnancy.