17 Weeks Pregnant: Pregnancy Symptoms & Baby Development

At 17 weeks your baby should weigh about 150g (just over 5oz)¹ and measure around 13cm from crown to rump². Until now, your baby’s head has been larger in proportion, but now its body is starting to catch up and put on weight. It’s around this time that fat-storing ‘adipose tissue’ is beginning to form³.

Hair, eyebrows and eyelashes are continuing to grow⁴. The respiratory system is also developing, and your baby will begin practising breathing as its chest rises and falls. By week 17, it’s possible for your baby’s heart rate to beat at around 140–150 bpm² – much faster than an average resting adult range of 60–100 bpm.

Your placenta is growing with your baby, delivering more oxygen and nutrients and removing waste from your baby’s blood⁶. By the end of your pregnancy, your placenta will weigh 500 grams. Just before birth, it will transfer antibodies which will help protect your baby in its first three months of life⁶.

With two things now growing in size, the most noticeable change will be watching your waist start to vanish. This happens as your womb moves up and out of your pelvis, highlighting your 17 weeks pregnant bump. You may also start showing the pregnancy ‘glow’ - radiant skin caused by a boost in hormones and blood volume⁷.

However, this transformation can make some women feel self-conscious and anxious. 10% of pregnancies show signs of stress or anxiety, and ever-changing hormones can make things seem worse than they are⁷. If you’re struggling, talk to your doctor, midwife or one of our 24/7 support team.

It’s recommended that you get 10 micrograms of vitamin D each day during pregnancy¹¹. The most efficient way to get vitamin D is through exposure to direct sunlight – UVB rays in particular. However, Britain’s latitude means we only get six months of effective sunlight each year, from April to September. This may explain why a significant number of young women in the UK have low vitamin D, and why sun exposure alone may not be enough to support your baby during pregnancy¹².

Vitamin D is present in certain foods, like eggs and oily fish. But the best way to make sure you’re getting enough is to take it as a 10mcg supplement. Some prenatal multivitamins contain this already, or you can choose to take a separate vitamin D supplement. You can also boost your vitamin D intake by including the following foods in your diet:

• Oily fish, including herrings, mackerel, sardines, salmon, trout (limit your intake to 2 portions a week).
  
• Eggs – the yolk contains the vitamin D.
  
• Fortified foods – some brands of milk and breakfast cereals have added vitamin D.

Some women experience headaches in early pregnancy. They usually improve or clear by the fourth month and don’t harm your baby.

Paracetamol is usually safe to take during pregnancy and while breastfeeding, but always at the lowest effective dose, and for the shortest possible time. When used correctly, there are no harmful effects to you or your baby¹⁵. Talk to your doctor or midwife for advice on how much paracetamol you should take, and for how long.

There are some painkillers you should avoid while pregnant or breastfeeding. These include non-steroidal anti-inflammatory drugs like Ibuprofen or Naproxen, and medications containing codeine and other opiates unless specifically directed by a healthcare professional¹⁵.

If you continue to experience headaches, it could be a sign of pre-eclampsia¹⁵. This can affect women around week 20 of their pregnancy or soon after giving birth.

The earlier pre-eclampsia is diagnosed, the better the outlook for you and your baby. Call your doctor, midwife or maternity unit if you develop a severe headache accompanied by:

• Blurred vision
  
• Seeing flashes of light
  
• A pain just below your ribs
  
• Vomiting
  
• Swelling in your face, hands, feet or ankles