15 Weeks Pregnant—Baby’s Lungs Are Developing

This week, you might start to notice additional pregnancy symptoms, such as sensitive gums, stuffy nose, and even nosebleeds. Now the size of an apple, your baby continues to grow rapidly. He’s now starting to “breathe” amniotic fluid, which is an important part of lung development.  

How big is my baby?

Baby’s Length: 3.98 inches.

Baby’s Weight: 2.47 ounces.

How is my baby developing? 

As each day passes, he’s looking more like the baby you’ll meet in a few months. His ears are almost completely formed and are moving into place (they started in his neck!), and his eyes are shifting to the front of his face. His arms and legs are becoming more defined, and toenails have started to grow. He’s now able to “breathe” amniotic fluid through his nose and into the upper respiratory tract, which is an important step in lung development.  

Though his eyelids will be fused shut for another 12 weeks or so, he is aware of changes in light. Your baby’s bones are growing harder and will be visible on an ultrasound soon, and taste buds are now starting to form.

At this point, your baby’s brain now controls all his little muscles. Though you probably won’t feel it yet, he can move, suck his thumb, and even do somersaults. He can frown, squint, and grimace as he uses his facial muscles. Don’t worry, though; these expressions aren’t an indication of mood.

What’s happening in my body?

Round ligament pain is likely to continue as your uterus and baby continue to grow and your muscles, joints, and ligaments stretch to accommodate. During your first trimester, your uterus fit inside your pelvis. Now, it’s stretching quickly to accommodate your growing baby. As your uterus outgrows your pelvis, it will move higher up in your belly.

You can now probably feel your uterus about three to four inches below your belly button, but you won’t be able to feel your baby from the outside just yet. To monitor your baby’s growth and position, your doctor or midwife will begin measuring fundal height, or the distance between the top of your pubic bone and the top of your uterus. Sometimes, fundal height can indicate if your baby’s in a breech or sideways position.

Your gums might be more sensitive, red, or swollen; some women develop gingivitis during pregnancy, which is an inflammation of the gums due to increased hormones and blood flow. Maintaining excellent oral hygiene is very important for you and your baby’s health.   

You might also notice that you’re feeling more congested. Even though you are at a higher risk for catching colds and the flu during your pregnancy, this new stuffiness might be caused by both hormonal changes and more blood going to the mucous membranes in your nose and sinuses. Some women experience nosebleeds due to blood vessel expansion in the nose and the additional blood volume.

About 90% of pregnant women experience some form of skin darkening during pregnancy. Most commonly, this affects your nipples, areolas, inner thighs, navel, and armpits. Some women may experience melasma or chloasma—the mask of pregnancy—which is a darkening around the eyes, nose, and cheeks. Some women also develop skin tags—small, harmless growths of skin—during pregnancy.

Feeling forgetful?

Pregnancy brain is real. Your brain cell volume actually decreases during pregnancy.

Make the most of the time when you feel good but allow yourself to rest and seek support when you need it. With additional testing can come additional anxiety. Remember to take extra care of yourself to manage any stress during this time. Some anxiety during pregnancy is normal, especially if this is your first baby. However, antenatal anxiety has been linked to poorer outcomes for both mothers and their babies. Always talk to your doctor about any worries and fears you have. Recent research has expanded the number of anxiety symptoms that can be considered robust indicators of anxiety.

What should I ask my doctor? 

The multiple marker screen (MMS), also called a triple screen or quad screen, may be performed between weeks 15 and 20. This is an optional, non-invasive test that tests levels of three (or four, in a quad screen) substances. 1) AFP, a protein produced by your baby; 2) hCG, the hormone produced by your placenta; and 3) estriol, an estrogen that both your placenta and your baby produce. In a quad screen, the MMS also measures the levels of inhibin A. Abnormal levels of any of these substances may indicate a developmental concern.  

This test alone is not diagnostic. The results are combined with other risk factors including age, results from other blood tests, and even your ethnicity, to determine your risk level. Even abnormal results may not indicate a problem. Of the 5% of women who receive abnormal MMS results, 2 – 3% will have abnormal babies. If your baby is older or younger than your doctor estimated—or if there’s more than one baby in there—it’s common to have an abnormal result.

If you’ve received an abnormal MMS result, your doctor will suggest a detailed ultrasound to more accurately assess your baby’s—or babies’—age. If those causes are ruled out, your doctor may recommend an amniocentesis.

Lindsay Meisel

Lindsay Meisel is the Head of Content at Ava. She has over a decade of experience writing about science, technology, and health, with a focus on women's health and the menstrual cycle. Her work has been featured on The Fertility Hour, The Birth Hour, The Breakthrough Journal, and The Rumpus.

Related posts

Related posts

By continuing to use the site, you agree to the use of cookies. More information Accept

This site is using first and third party cookies to be able to adapt the advertising based on your preferences. If you want to know more or modify your settings, click here. By continuing to use the site, you agree to the use of cookies.