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15 weeks pregnant

Your baby at 15 weeks

She is about 11cm long and weighs 70g.

  • Foetus at 15 weeks pregnantYour baby is developing cheekbones. If she is going to have dark hair, then the hair follicles will soon start making the pigment responsible for the colour.
  • Her little ears and firmly shut eyes have almost reached their final positions although her ears are still a bit low. She seems to squint in the light sometimes. Her skin is still thin.
  • She's more in proportion: her legs are now longer than her arms, as it should be.
  • All that muscle and bone development has come up with something useful - a baby fist. Her arms and legs have also grown so much that she looks like a baby human.
  • The little bones in the inner ear start to harden so they can vibrate and transmit sounds - she can start to really hear. Before this she knew she wasn't alone - she could feel the vibrations of your voice and your heartbeat. Your uterus is noisy but sounds are muffled through the amniotic fluid. She should be able to hear your heart beat, the whooshing of blood in your veins and your stomach gurgling. As her hearing improves, she will be able to hear your voice and other sounds outside the uterus. When she is born she will recognise your voice.
  • She has sophisticated taste buds (they look as mature as an adult's) and if she had the ability for conscious thought (which she does not) she would recognise flavours in the amniotic fluid she gulps down as she practises swallowing. Amniotic fluid can smell of onions, curry, garlic and cumin from a mother's diet. 

Your body at 15 weeks pregnant

  • Don't feel down if you still feel tired, sick, spotty and fat. The bloom of pregnancy is more likely to touch you than not, but it can take a while to glow and some women can blink and miss it.
  • Vaginal discharge You may have noticed for a few weeks that you are haunted by an annoying discharge that is not smelly but is still white and a bit messy. This comes from the more rapid turnover of cells lining your vagina, mixed with normal vaginal moisture. This mixture is thought to protect your vagina - the point of entry to your foetus - from harmful bacteria. But if this discharge is tinged with blood, becomes watery, gets greenish and smelly then see your antenatal team quite quickly. You could have an infection.
  • Thrush This cause of odourless white vaginal discharge deserves a paragraph of its own because so many pregnant women get it. It causes itching and soreness and can make it hurt when you pass urine because the area around your urethra gets inflamed. A single pessary put into your vagina (it's safe for the foetus) often works. Thrush can look like cottage cheese and is common in pregnancy because the pregnancy hormones make the vagina less acidic, so this yeast-like fungus, which is already in the vagina in small amounts, can get a foothold.
  • Stretch marks Almost 90% of pregnant women get stretch marks. So the livid red lines you see across your upper thighs or running down your abdomen or breasts are not your unique pregnancy battle scars. They are not treatable, no cream can reverse them, but time will make their redness fade. Putting on weight gradually can help avoid them. Stretch marks are caused by the layer of collagen under the skin tearing as your skin stretches over your enlarging body. It starts early in pregnancy on breasts and then your abdomen, hips and thighs. The risk of stretch marks is partly genetic and also age-related - older people may have less elastic skin.



Pregnancy Encyclopedia book coverIllustrations taken from The Pregnancy Encyclopedia, £25, published by DK.

Disclaimer: The information in the pregnancy calendar is for general information and is not intended as a substitute for the medical advice of your own doctor or antenatal team. Not all babies develop at the same time and in the same way, so this week-by-week guide may not always match your own experience. If you have any worries, consult your antenatal team or GP.

Last updated: 4 months ago