13 Week Ultrasound: Changes at the End of the First Trimester


After the first trimester of pregnancy, you can start to relax a little: the risk of having a miscarriage drops significantly and you can be sure about being pregnant. Your baby is now starting to look like a baby than an embryo and is growing fast. The small embryo now has a strong heart beat and a defined body, with a large, disproportionate head. There are more details you can see at your first trimester ultrasound from gender and wrists to potential abnormalities and illnesses, let’s check on all the wonderful changes of your little tadpole.

How Is Your Baby at the Thirteen Week?

13 week ultrasound 3D
Source: http://www.pregnancysymptomsweekbyweek.org/

At 13 weeks of age, your baby measures about 7-8 cm long and is the size of a large egg or a peach, weighting about 25g. If you are looking at an egg you are going to be a little disappointed by the size, yet the baby is already moving around. At the 13 week ultrasound, you can hear the strong heartbeat of the baby and see him turning around, kicking and yawning. You might start to feel him hiccupping or kicking, but it’s still early for the real kicks, which come in the fourth month of pregnancy. Despite it is very small, the baby should be active at this age.

The baby’s skeleton is starting to develop, so your doctor will check how the bones and articulations are developing. The clavicle, collarbone and the thigh bone are the most significant bones at this age.

Your baby is also developing organs: it has a stomach, bowels and vocal chords. However, the most important organs which are developing at this stage are the lungs: the baby is starting to “breathe”. You will be able to see the baby opening his mouth at the 13, 14 week ultrasound, but they are only exercising, as it gets all the oxygen from the umbilical cord.

The kidneys start to function at this age and the baby will start to pee in the amniotic liquid which surrounds him.

Your Baby’s Gender And Body

At 13 weeks of pregnancy the gender of the baby is visible, but you shouldn’t start buying blue or pink items yet: the umbilical cord can be mistaken for a penis. If the baby is a girl, it will have about 2 million eggs in her ovaries! Impressing, right? The number of the eggs will drop to one million before she is born.

The baby is developing its facial muscles, exercising the moves he will use during nursing, after birth. One of the most emotional images for the future parents is the image of the little fingers: at the 13 (or 12) week ultrasound you can see the baby’s fingertips and watch him moving the hands and legs. The baby can even put his thumb in his mouth, to suck.

All in one, the baby is starting to look like a human being. His head is still very big, compared to his body, but the body is catching up fast. The tissues are still forming, so the baby is pretty transparent and the veins can be seen. His heart beat is twice as fast as an adult’s, but this is normal, so enjoy the sound of it.

[Read more about Gender]

How Your Body Changes at the End of the First Trimester?

Baby at 13 weeks ultrasound
Source: https://community.babycenter.com

At the end of the first trimester you start to experience more symptoms of pregnancy and you get the pregnancy look. The morning sickness is slowing fading out and you start to gain weight. In most women all the unpleasant symptoms fade out along the morning sickness, but you still have to pee more often than usual. Your ribcage expands, to make room for the growing uterus and your belly button is sticking out. The uterus is moving up, developing a small bump in your belly, which you can easily notice, but it won’t be visible for the rest of the world. The uterus will feel like a soft ball in your belly. You can still wear your regular clothes, but they will feel tighter.

No More Mood Changes

13 weeks pregnant symptoms
Source: https://www.pinterest.com

In the first trimester of pregnancy, many women deal with an increased sense of smell and lots of mood changes; these disappear in the second trimester, so you will start to feel better with each day.

As the nausea is gone, because the placenta is now developed and it takes over the production of hormones and other bodily functions your baby needs, you can start to bloom. Your skin will be glowing, due to increased blood flow and the larger amount of water you are drinking. Your confidence is also growing, as the risk of miscarriage lowers. Many couples and pregnant women choose the 13 week to make the public announcement.

Despite you still don’t have to change your wardrobe, you should take advantage to buy some pregnancy clothes: when you will be large and heavy, shopping might not be as pleasant as always.

At this stage of the pregnancy, your body releases a hormone which promotes relaxation of the muscles and ligaments, so you might become a little clumsy. But your energy level will return to normal, allowing you to compensate for the clumsiness. Another positive side of this stage is the fact you will start to look very sensual. The hormone rush makes your breast larger, your lips fuller and your eyes brighter.

You have to remember each pregnancy is different: if you are still experiencing nausea and drowsiness, you shouldn’t worry too much. Just check with your doctor.

As you enter your second trimester you can think of having a last holiday before the baby arrives. Most airlines have strict rules regarding pregnant women, so you might be running out of time when it comes to flying for a holiday or to visit your relatives. Speaking of relatives, couples who live away from their families need to decide where the birth will take place and start packing; otherwise you might find yourself away from family at the moment of the birth, as you won’t be allowed to fly in later stages of the pregnancy.


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