Your baby's position in the womb changes with the pace of his mental and physical development. The third trimester of your pregnancy heralds many physical changes in the womb and your baby. All of his organs are fully developed by the seventh month and many babies explore their bodies by grasping toes and fingers and sucking on their thumbs. Your baby's natural inclination toward movement is temporarily hampered as space becomes increasingly limited.
Running Out of Space
The end of your second trimester brought many new developments to your baby that increased her capacity to think and feel. During the seventh month of development, significant increases in height and weight decreased his womb space and ability to explore developing senses. Your baby's kicks and jabs will be less frequent and more forceful during this time due to the limited amount of space in your womb, according to Womenshealth.gov. You may also experience frequent heartburn and indigestion during this time.
Baby's Sensory Development
As your baby's senses develop during the seventh month of gestation, he responds to external stimuli through movement. Heat, cold, pressure, pain and sound serve as major information channels between your baby and the external world. You may feel sudden jerks and kicks after loud noises occur, according to Parents.com. Soft music, the sound of your voice and steady heartbeat and other soothing sounds will often settle your baby into a relaxed state.
Your Baby's Sleep
By the beginning of your third trimester, your baby's lifetime sleep cycle, or circadian rhythm, has already been established. This cycle might be similar to or vastly different from yours. This, along with the increasing size of your baby, can make finding a comfortable sleeping position difficult. Sleeping on your left side with a pillow between your knees can help relieve much of this discomfort while improving circulation and blood flow to your baby, says KidHealth.org.
Preparing for Birth
Typically, the seventh month of pregnancy ends with your baby descending into the occipito-anterior -- head-down, face toward spine -- position to prepare for birth. Sometimes, babies head down but remain face up. This position increases risks of severe back pain during labor, says PregnancyToday.com. You can help your baby reach the best head-down position by avoiding sitting positions that place your knees higher than your pelvis. Leaning back and crossing your legs should be avoided.