The Inside Story: Your Baby in Week Thirteen

As you enter your second trimester, your baby is growing quickly--and you will be able to hear his heartbeat at your next doctor's visit!

Your baby is ramping up his growth rate. Your baby's organs, now fully formed, will mature during this trimester in preparation for life after birth. You still supply his oxygen through your bloodstream, but your baby will exercise his lungs and work his chest muscles. His kidneys are getting some practice too, and the amniotic fluid now contains fetal urine. The placenta is working alongside your baby, producing hormones and red blood cells.

His skin is becoming more waterproof. His heartbeat will start slowing down, but it will be strong enough for you to hear during your prenatal visit. His brain is continuing to grow. In fact everything will start growing so fast this month that your baby will almost double in length by the end of the 2nd trimester. Grow, baby, grow!

Pregnancy Month by Month: Month 4
Pregnancy Month by Month: Month 4

Originally published in You & Your Baby: Pregnancy.

All content on this Web site, including medical opinion and any other health-related information, is for informational purposes only and should not be considered to be a specific diagnosis or treatment plan for any individual situation. Use of this site and the information contained herein does not create a doctor-patient relationship. Always seek the direct advice of your own doctor in connection with any questions or issues you may have regarding your own health or the health of others.

Find a Baby Name

Browse by

or Enter a name

Parents Are Talking

Add a Comment