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First trimester weeks

Congrats! During the first trimester, you’re getting used to the idea of being pregnant.

Second trimester weeks

As you enter this second trimester, your body will settle down to pregnancy.

Third trimester weeks

You've reached the third and final trimester and will be heavily pregnant by now.

Week 17 of Pregnancy

Your baby is increasing his movements and even doing somersaults.

Things are becoming lively in your uterus. Your baby has plenty of room to move around and he's making the most of it, stretching and turning. All the activity is good for his future physical and mental development. You might feel like some relaxation, so think about taking a break. The second trimester is usually regarded as the best time in pregnancy for traveling and getting out and about.

16 Weeks, 2 Days

166 days to go...

ultrasound of human fetus at 16 weeks and 2 days

Your baby today

In this color 2D ultrasound scan the baby is facing upward. The skull bones reflect the ultrasound beam most effectively and show as bright areas. The curved frontal bone of the forehead is seen just above the short nasal bone forming the bridge of the nose.

Your baby is at his most mobile about now, and he may even be doing somersaults in your uterus.

There are several ways in which your baby can now move: he can curl and stretch his trunk, move his head up and down and from side to side, and move his arms and legs independently. Regular chest wall breathing movements occur, along with occasional hiccups. The mouth can open and shut, and your baby can yawn and swallow amniotic fluid. He'll bring his hands up to the face and prefer lying on his side rather than back. He has plenty of space in which to move.

Your baby's taste buds first appeared at 10 weeks and by now have an appearance very close to that of a mature taste bud. They also have their own nerve supply, connected to a branch of the facial nerve. Because these neural connections have not yet matured, it is too early for your baby to be able to taste anything.

Focus On... Twins

How your babies interact

By now, you may be starting to feel your twin babies move. Contact between them probably began a few weeks ago, long before you knew about it, and it becomes more complex as their brains develop. By this stage of pregnancy, a baby has the elementary brain circuits that help him feel the parts of his body and appreciate their position, so it's no wonder that your babies can now interact at a basic level.

Your babies will move around 50 times an hour and can touch each other, even though in all but a tiny percentage of cases they're in separate amniotic sacs so there's a membrane between them. Ultrasound studies show that twin babies make physical contact and sometimes react to each other's touch and pressure.

Ask A... Doctor

What is DVT and am I at increased risk of it when I fly?

DVT stands for deep vein thrombosis, a condition in which a blood clot forms in a deep leg vein. DVT partially or completely blocks the blood flow in the vein, causing pain and discomfort. The most serious form of DVT is a pulmonary embolism, when part of the clot breaks off and travels to the lungs, blocking a pulmonary artery. This can cause chest pain, shortness of breath, and blood-tinged phlegm to be coughed up. In severe cases, a pulmonary embolism can be fatal.

Pregnancy is considered to be a thrombotic condition, meaning it can lead to clots forming in blood vessels, so you are at increased risk of DVT even when you're not traveling by plane. Women who have previously had DVT or who are obese are more at risk of getting the condition.

Wearing support stockings, drinking plenty of fluids, and moving around while flying can help prevent DVT. If you've had blood-clotting issues in the past, avoid flying at all during pregnancy.

16 Weeks, 2 Days

166 days to go...

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