Week 13

You may start to notice the more troublesome symptoms of the first trimester, such as nausea and fatigue, begin to ease as you go into the second trimester. These symptoms usually subside by 20 weeks for most people.²

During pregnancy, you may notice some skin changes due to the elevated hormones surging throughout your body. These may include:¹

• Increased acne

• Hyperpigmentation resulting in:³

  • Chloasma: brown patches commonly found on the face
  • Linea nigra: a dark vertical line from the pubic bone to the belly button
  • Peri-areolar: darkening of the areolas around the nipples

However, these changes may also affect any moles you may have. If you notice any shape or colour changes to any moles, it is best to get these checked by your healthcare provider.¹

• Constipation
• Fatigue
• Dizziness
• Food cravings and aversions
• Visible veins
• Heartburn and indigestion
• Changes in libido
• Skin changes
• Vaginal discharge

Weighing around 28 g and measuring the size of a lemon, your baby is still developing at a rapid rate.¹

Between pregnancy weeks 12 to 13, the nerve network between the tongue cells that will determine your child’s tastes (and distastes) are densely connected now.⁴ Additionally, the tiny structures that will help your baby hear are taking shape this week. The ear canal is blocked by a structure called the meatal plug. This will help form the outer layer of the ear drum.⁴

• Consistently taking folic acid is recommended,⁵ or if you haven’t already, consider taking a prenatal supplement that has the recommended amounts of vitamin A and D, iron and calcium⁶
• Staying active and keeping a healthy weight can help support fertility and overall health⁷
• Try to avoid alcohol consumption and smoking – both are known as risk factors for miscarriage^8,9
• Nourish your body with pregnancy-safe foods (if nausea and morning sickness allow)   
  You should try to avoid foods high in mercury, such as mackerel and tuna, raw seafood, undercooked meat, poultry and eggs, unpasteurised foods and cheese with a mould rind such as brie, unwashed fruits and vegetables, and any type of herbal tea.¹⁰
• Limit caffeine consumption to no more than 200 mg per day¹¹         
  As a guide:         
  1 mug of coffee contains 100 mg of caffeine         
  1 mug of tea contains 75 mg of caffeine         
  1 can of cola contains up to 40 mg of caffeine         
  1 bar of chocolate contains up to 50 mg of caffeine   

During your first antenatal scan, your sonographer will be looking to identify the required structures to first confirm the pregnancy is in the correct location within the uterus, and they should be able to distinguish how many weeks pregnant you are. This first scan can sometimes be referred to as the “dating scan”.

When performing the scan, with a pregnancy at 13 weeks the sonographer will look for:

• A gestational sac within the uterus, this is referred to as an intrauterine sac
• Within the gestational sac, there should be a clear foetus with a heartbeat
• For 13 weeks, the foetus should measure approximately 6.4 cm from the top of the head (crown) to the bottom of their buttocks (rump)
• Any indication of abnormalities, including any heart defects and increased nuchal translucency (fluid at the back of the neck), as these may require more monitoring during your pregnancy

If you’re concerned about your first antenatal scan, speak with your healthcare provider for further support and information.