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Pregnancy weeks

Pregnancy week 17

The first baby fat


You have reached the beginning of the fifth month of pregnancy and now the biggest visible change in the second trimester is starting: your baby bump is growing! This is largely because your baby is putting on weight. Read on to discover what else is going on in the 17th week of pregnancy.

What's going on inside you at 17 weeks pregnant?

The size of the foetus is around 11-14 cm (CRL = crown-rump length) and it weighs approx. 100-150 grams. The feet are 2 cm long and the diameter of the head is around 4 cm.

Your little one has moved more towards being a "cute little baby". The proportions are more like those that will appear at birth. The legs have grown longer, the head is no longer disproportionately large and the foetus is slowly gaining a little baby fat. This layer of fat will later help to maintain the body temperature. Until this point it is one of the tasks of the amniotic fluid to keep baby consistently warm.

Your baby is now roughly the size of an orange.

Your baby is now roughly the size of an orange.

The sense of hearing has developed further. Your baby now responds to loud sounds: sudden noise can even startle it – you may feel these vigorous movements as a gentle fluttering in your belly (if not, this isn't unusual – it can take up to the 20th week of pregnancy or even longer before you notice movements). 

You can now hear something from outside too: the baby's heartbeat is perceptible with a stethoscope.

How do you feel at 17 weeks pregnant?

Your baby's growing a layer of fat, together with the amniotic fluid, to help regulate its body temperature. So your bundle of joy is well-protected; even if you have a long hot bath. But you should note the following points during and after your bath:

  •  If you didn't take hot baths or were not used to saunas before getting pregnant, it is best not to start now. 
  • Hot temperatures can affect the circulation. If you feel unwell, reduce the heat of the bath water.
  • Avoid public Jacuzzis due to the possibility of infection with bacteria and ideally bathe in your own bathtub.
  • Drink plenty of water before and after – this will also help your circulation.
  • Moisturise your skin well after your bath in order to prevent stretch marks.
  •   Your skin will absorb moisturisers especially well after a bath. But do check the quality and ingredients in your skincare products. Some ingredients can harm your and/or the baby's health as they pass through the placenta.

What causes the dark line on your stomach?

An expectant mother's skin changes due to the pregnancy hormones. Large quantities of melanin are also produced. Melanin is the substance that is responsible for pigmentation, i.e. the colouration of the skin. Mums-to-be therefore tend to have more pigment spots, freckles and a special phenomenon: the linea nigra (or linea negra). This extends vertically over the entire stomach, exactly in the middle of your body, and passes through the navel. It is generally more pronounced in women with darker skin tones. Everyone has this line, but it is normally so light that it cannot be seen.

The increased pigmentation generally disappears on its own after the birth. Expectant mothers should never use skin-lightening creams due to the chemicals they contain. It is better to use a good sun cream with a high sun protection factor or to avoid the sun altogether if this is possible.


Why do expectant mothers sometimes sweat more at this point, and why is iron important?

The volume of blood has increased to supply the baby. This increased blood flow may make you sweat more readily. Sweating cools your body, but also causes minerals to be eliminated. So an adequate supply of minerals from your diet is particularly important now.

The body also needs iron to produce blood. During your pregnancy, your Midwife or Doctor will generally take blood samples to check your iron levels. If your level is too low, your Midwife or Doctor can advise you which foods you should eat or whether you need to take a dietary supplement.

It is not a good idea to start taking iron supplements off your own bat as they can have unpleasant side effects. Digestive issues, in particular, are common. Too much iron can also harm your baby.


Iron-rich foods:

  • Red meat (beef, veal, game)
  • Wheat bran
  • Millet
  • Soya
  • Pumpkin seeds
  • Pulses
  • Egg yolk

Vitamin C promotes the absorption of iron – one glass of orange juice with your meal, and peppers, tomatoes or fruit as an accompaniment are not just delicious, they are actually recommended!


Photo: Shutterstock

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