The ultimate guide for your 21 week ultrasound.

The ultimate guide for your 21 week ultrasound.


Hi mommies, this week the changes in the development of your baby are exciting, as you already noticed today we are going to talk about your 21-week ultrasound, I hope you’re having an amazing day. As usual, you are going to find ultrasound images combined with all you need to know about your 21-week pregnancy in this post, so let’s begin…

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How Big Is your Baby at 21 Weeks Pregnant?

At 21 weeks pregnant, the baby is as big as a Pomegranate. The average 21-week fetus weighs about 12.7 ounces and measures 10.5 inches long.

Your baby is big enough now that you’ve probably been feeling his or her fetal movements more and more lately.



Your 21 Weeks Pregnant Symptoms.

Braxton Hicks contractions: You might start noticing mild contractions at this point, some patients more than others, Braxton hicks contractions is when your uterus occasionally feel tight as it practices for labor. This is totally normal as long as the contractions go away when you change positions. Let your doctor know about any pain or contractions that don’t stop, Keep in mind that Dehydration can cause Premature Labor, so try to keep yourself hydrated at all times. If you are pregnant with twins expect to be feeling more of this contractions.

Stretch marks: Stretch marks are a form of scarring on the skin. Over time they may diminish, but will not disappear completely. Stretch marks usually form during the second and third trimester, and usually on the belly, but also can occur on the breasts, thighs, hips, lower back and buttocks. These are known as striae gravidarum. Stretch marks are more common for some women simply because of family history, lack on collagen or because of sudden weight gain.

Dry, itchy skin: Your skin is stretching over your growing bump, making it more irritated by the day. Using a pregnancy safe body oil or lotion will help your skin stay moisturized and hopefully less itchy. Also, if you develop a rash, let your doctor know right away.

Leaky boobs: Your milk ducts will be fully developed by the end of this trimester just in case of early arrival.

Heartburn and/or indigestion: Avoid spicy and greasy foods and other triggers. If the source of your discomfort is a mystery, keeping a food diary could help you figure it out.

I want to remind you that other symptoms such as Vaginal discharge, Hip pain, and Abdominal aches might be part of your normal second-trimester list of symptoms. All normal and part of the process of growing a baby in your uterus, try to rest when you have the chance, stay hydrated, try to have a healthy and balanced diet, and give yourself a lot of love.

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22 week pregnancy and ultrasound

Maintaining your skin moisturized at this point is a plus, it will make you feel less itchy and irritated, Some recommended products to you at 21 weeks are:

I will leave some of my previous posts linked below in case you want to check them out.

The ultimate guide for your 20-week ultrasound, Fetal development, all you need to know about your pregnancy this week.

The ultimate guide for your 19-week ultrasound, Fetal development, all you need to know about your pregnancy this week.


What is happening with your baby at 21 weeks?

Baby’s Taste Buds Develop: When you’re 21 weeks pregnant, your baby is swallowing amniotic fluid each day not only for nutrition and hydration but also to practice swallowing and digesting, skills he’ll need as soon as he arrives.

Baby’s Getting Coordinated: Arms and legs are finally in proportion, neurons are now connected between the brain and muscles and cartilage throughout the body is turning to bone. All these upgrades combine to give your baby more control over limb movements, which explains all that kicking and stretching you may have started feeling.

The reproductive system is developing too: If it’s a girl, she’s already got a lifetime supply of eggs in her womb about six million of them, If its a boy, His testes are still located in his abdomen but will drop in the coming weeks once the scrotum finishes developing.

What to know about doctor visits.

Your doctor will measure the fundal height at each prenatal visit at this point. Fundal height is the distance from the pubic bone to the top of your uterus. In centimeters, the fundal height should match your week of pregnancy, give or take two centimeters.
It should continue to increase about a centimeter each week. A higher or lower fundal height could be the sign of a pregnancy condition such as gestational diabetes, a growth issue, or a breech baby, so if it doesn’t appear to be average, further testing may be necessary.

If there is any questionable-size discrepancy then Ultrasound is the way to go to check fetal growth.

At this point, Ultrasound is only done under certain circumstances, only if you are experiencing Pelvic pressure, Pelvic pain, vaginal bleeding and/or vaginal discharge.

Ultrasound Biometrics at 21 weeks is as follow.

*Biparietal Diameter( BPD )
*Head circumference( HC )
*Abdominal circumference( AC )
*Femur length( FL )

Measurements on the Amniotic Fluid levels are also done.

Checking out Placenta again, Anterior or Posterior Placenta is fine as long as the placenta isn’t Previa ( covering cervical canal ) is all fine.

Ultrasound doesn’t need to check again major organs and intracranial structures because that was already done on the Anatomy Scan.

But, are you curious to know how your baby looks at 21 weeks? check it out!

21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

Measurement of the fetal head


21 week baby ultrasound

Measurement of the Abdominal circumference


21 week baby ultrasound

Measurement of the Femur


21 week baby ultrasound

21 week baby ultrasound

Normal fetal heart rate should be between 120 to 170 bpm.


21 week baby ultrasound

21 week baby ultrasound

21 week baby ultrasound

OK friends, so this is the most important information about your 21-week ultrasound and doctor visit.
Thanks for staying with me until the end, I hope this post was helpful to you, on my next post I will be talking about 22-week pregnancy and ultrasound, thanks for visiting my blog today, I will see you next time.

XO Zadi.

Disclaimer: Due to HIPPA compliance and regulations all patient information is protected on this site. Also, the information provided on my blog is designed to provide helpful information about the topic and are made with the best of my knowledge, therefore, is not intended to diagnose or treat any medical condition, For diagnosis or treatments on any medical problems consult your own physician. The author is not responsible or liable for any mistreated pathologies or wrong treatments.

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Ultrasound sonographer for many years and mommy of 2 boys, I love my kids therefore I love what I do, help other women to achieve a healthy and successful pregnancy is my goal.

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