Do You Know How Babies ʙʀᴇᴀᴛʜe In The ᴡᴏᴍb
Developing babies need ᴏxʏɢᴇɴ beginning early in pregnancy. But a baby won’t take their first ʙʀᴇᴀᴛʜ until after birth. This means that babies don’t truly ʙʀᴇᴀᴛʜe in the ᴡᴏᴍb. Instead, the ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ provides the baby with ᴏxʏɢᴇɴ until the first ʙʀᴇᴀᴛʜ.
Lung development begins early in pregnancy, but is not complete until the third trimester. Between 24–36 weeks of pregnancy, the ʟᴜɴɢs begin developing alveoli – the tiny ʟᴜɴɢ sᴀᴄs that fill with ᴏxʏɢᴇɴ. Until these sacs are fully developed, a baby may have difficulty ʙʀᴇᴀᴛʜing on its own outside of the ᴡᴏᴍb.
How do babies ʙʀᴇᴀᴛʜe in the ᴡᴏᴍb?
Several biological systems and processes play a role. They include:
The ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ
After 5-6 weeks of pregnancy, the ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ develops to deliver ᴏxʏɢᴇɴ directly to the developing fetus’s body. The ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ connects to the ᴘʟᴀᴄᴇɴᴛᴀ, which is connected to the ᴜᴛᴇʀᴜs. Both sᴛʀᴜᴄᴛᴜʀᴇs ʜᴏᴜsᴇ ᴍᴀɴʏ ʙʟᴏᴏᴅ ᴠᴇssᴇʟs, and continue to grow and develop throughout pregnancy.
Together, the ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ and ᴘʟᴀᴄᴇɴᴛᴀ deliver nutrients from the mother to the baby. They also provide the baby with the ᴏxʏɢᴇɴ-rich ʙʟᴏᴏᴅ necessary for growth.
This means that the mother ʙʀᴇᴀᴛʜes in for the baby, and the ᴏxʏɢᴇɴ in her ʙʟᴏᴏᴅ is then transferred to the baby’s ʙʟᴏᴏᴅ. The mother also ʙʀᴇᴀᴛʜes out for the baby, as carbon dioxide from the baby is moved out through the ᴘʟᴀᴄᴇɴᴛᴀ to the mother’s ʙʟᴏᴏᴅ, the removed with ᴇxʜᴀʟᴇ
Substances going into the developing baby, such as ᴏxʏɢᴇɴ, never interact with the substances leaving the baby, such as ᴡᴀsᴛᴇ ᴘʀᴏᴅᴜᴄᴛs. They travel through the ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ through two separate ʙʟᴏᴏᴅ vessels.
Lung development in the ᴡᴏᴍb
Lung development is normally complete after 35-36 weeks of pregnancy. However, development ᴠᴀʀɪᴇs and it’s possible to miscalculate when a baby was conceived. This is why even late ᴘʀᴇᴛᴇʀᴍ babies often experience difficulties ʙʀᴇᴀᴛʜing. Steroids may help speed the development of a baby’s ʟᴜɴɢs. When a woman must give birth early, or when she is at risk of ᴘʀᴇᴛᴇʀᴍ labor, doctors may recommend steroids given to the mother to improve a baby’s chances of sᴜʀᴠɪᴠᴀʟ outside the ᴡᴏᴍb.
Even when a fetus’s ʟᴜɴɢs are fully developed, it’s impossible for the fetus to ʙʀᴇᴀᴛʜe until after birth. Developing babies are sᴜʀʀᴏᴜɴᴅᴇᴅ by ᴀᴍɴɪᴏᴛɪᴄ Fʟᴜɪᴅ, and their ʟᴜɴɢs are filled with this Fʟᴜɪᴅ. By 10–12 weeksTrusted Source of gestation, developing babies begin taking “practice” ʙʀᴇᴀᴛʜs. But these ʙʀᴇᴀᴛʜs provide them with no ᴏxʏɢᴇɴ, and only refill the ʟᴜɴɢs with more ᴀᴍɴɪᴏᴛɪᴄ Fʟᴜɪᴅ. Because it’s normal for a fetus’s ʟᴜɴɢs to be filled with Fʟᴜɪᴅ, a fetus can’t ᴅʀᴏᴡɴ ɪɴ ᴛʜᴇ ᴡᴏᴍʙ.
If there is a problem with the ᴘʟᴀᴄᴇɴᴛᴀ or ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ, there’s no other way for a developing baby to ʙʀᴇᴀᴛʜe. As a result, issues with these structures can cause birth ᴅᴇFᴇᴄᴛs, ʙʀᴀɪɴ ɪɴᴊᴜʀɪᴇs, ᴏʀ ᴇᴠᴇɴ ᴛʜᴇ ᴅᴇᴀᴛʜ of the fetus.
ʙʀᴇᴀᴛʜing during and after birth
Some babies are born with the ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ ᴡʀᴀᴘᴘᴇᴅ ᴀʀᴏᴜɴᴅ ᴛʜᴇ ɴᴇᴄᴋ. This relatively common issue, called a nuchal cord, happens in 12-37 percent of birthsTrusted Source. In most cases, it causes no problems. This is because the ᴜᴍʙɪʟɪᴄᴀʟ ᴄᴏʀᴅ is still able to provide the baby with ᴏxʏɢᴇɴ.
However, if the cord is wrapped very tightly around the ʙᴀʙʏ’s ɴᴇᴄᴋ, the ᴏxʏɢᴇɴ supply in the cord might be limited. During birth, the care provider will check for a nuchal cord, and if possible, unwrap the cord. Once the baby is born, the new environment – which includes ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇ changes, a lack of ᴀᴍɴɪᴏᴛɪᴄ Fʟᴜɪᴅ, and exposure to air – triggers the baby’s first ʙʀᴇᴀᴛʜ.
Some babies have their first bowel movement during birth, before exiting the ᴡᴏᴍb. This stool is called ᴍᴇᴄᴏɴɪᴜᴍ. During a practice ʙʀᴇᴀᴛʜ during or shortly before birth, a baby may inhale ᴍᴇᴄᴏɴɪᴜᴍ. Inhaling ᴍᴇᴄᴏɴɪᴜᴍ can be serious and can ʜᴀʀᴍ a baby’s ability to ʙʀᴇᴀᴛʜe outside the ᴡᴏᴍb. So babies who have inhaled ᴍᴇᴄᴏɴɪᴜᴍ may need ᴛʀᴇᴀᴛᴍᴇɴᴛ with suction and ᴏxʏɢᴇɴ after birth.