How does a baby feed while in the womb
When does the placenta form, and what does it do? Learn all about the placenta.
One of the many remarkable things about pregnancy is that you're not only growing a new human being, but also an entirely new organ. And pretty much everything your baby needs to develop and thrive flows through it. Find out all about the amazing placenta, including when it forms and what it does.
What is the placenta?
The placenta is a pancake-shaped organ that develops within the wall of your uterus and connects to your baby though the umbilical cord. By the end of pregnancy, it grows to be about 9 inches in diameter and about an inch thick at the center.
What does the placenta do?
- It delivers oxygen and nutrients (such as vitamins, glucose, and water) from your body to the baby's, and processes the waste products from your baby.
- It produces the hormones that help your baby grow and develop.
- It allows antibodies to pass to your baby from your bloodstream.
These antibodies protect against certain bacterial infections and viral illnesses, like diphtheria and measles, until after your baby is born and old enough to get their first vaccinations.
When does the placenta form?
The placenta starts forming as early as six days after fertilization. At this point your baby-to-be is a hollow ball of several hundred cells called a blastocyst. The blastocyst attaches to the lining of the uterus, usually near the top. This is called implantation, and it's completed by day 9 or 10.
The wall of the blastocyst is one cell thick except in one area, where it's three to four cells thick. In the thickened area, the inner cells develop into the embryo. The outer cells throughout the embryo burrow into the lining of the uterus and develop into the placenta.
The placenta produces several hormones that help maintain the pregnancy, including human Chorionic Gonadotropin (hCG), which prevents the ovaries from releasing eggs and stimulates the ovaries to produce estrogen and progesterone continuously.
(Home pregnancy tests measure levels of hCG in your urine.)
The placenta is fully formed by 18 to 20 weeks but continues to grow throughout pregnancy. At delivery, it weighs about 1 pound.
How the placenta works
The placenta connects to the umbilical cord through thousands of microscopic "fingers" of tissue (chorionic villi) containing a network of blood vessels that connect to the embryo's circulatory system. The villi are formed by 6 weeks of pregnancy, and your blood fills the spaces around them by 12 weeks. When your blood comes in contact with the villi, nutrients are exchanged for waste through the villi walls.
The villi also act as a filter, preventing some viruses and bacteria from reaching your baby, while allowing molecules of everything you ingest as well as antibodies and gases to pass through.
How do babies get nutrients in the womb?
Your baby needs nourishment from the get-go. Until the placenta is developed enough to provide nutrients, your baby receives nutrients from the lining of the uterus, called the endometrium.
(These same endometrial cells will quickly multiply to form the placenta.)
In the early weeks of pregnancy, glands in the uterine lining secrete glucose, which it stores as glycogen. At first, this glycogen is the only source of nourishment for your baby.
At about 8 to 12 weeks into pregnancy, the placenta takes over as a nutrient source for your baby. (And at this point the uterus stops secreting glycogen.) Here's how it works:
- When you eat, the food travels to your stomach, where it's broken down (digested) into glucose, fats, vitamins, minerals, and protein.
- The nutrients are absorbed into your bloodstream and travel to the placenta.
- Blood vessels in the umbilical cord pass the nutrients from the placenta to vessels that flow from the umbilical cord to the baby. At this point, your baby will begin to gain weight more quickly. The umbilical cord also returns waste products from your baby to the placenta and into your circulation for elimination.
Wondering how fast the food you eat reaches your baby? It depends on how quickly the food is digested and enters your bloodstream. Some foods may take several hours, while substances like caffeine can enter your bloodstream and cross the placenta in a very short time. For more information, watch our video on how food reaches your baby.
Harmful substances that cross the placenta
Along with all the good things that are transferred to your baby, some harmful ones can cross the placenta too. These include alcohol, nicotine, and illegal drugs as well as some medications.
No safe level has been established for alcohol consumption during pregnancy, and experts recommend not drinking any amount while you're expecting. The same goes for smoking and using illegal drugs. Although marijuana is legal in some states, experts recommend against using it during pregnancy.
Use caution when taking prescribed and over-the-counter medications during pregnancy because most cross the placenta.
Although many medications are considered safe for your baby, a few are known to cause birth defects. And for many drugs, there simply is not enough research to know their effects on an unborn baby. Your provider can help you determine whether the benefits of a certain drug outweigh the risks in your case.
Although the placenta acts as a barrier to most bacteria, some viruses and small bacteria can cross it. Many have no effect, but others can be harmful to a developing baby. That's one reason why it's important to get all recommended vaccinations before and during pregnancy, including a flu shot and a Tdap vaccine to protect against tetanus, diphtheria, and pertussis (whooping cough).
Both the flu and pertussis can be life-threatening for babies, and getting these vaccines while you're pregnant enables antibodies to pass through the placenta that will protect your newborn from catching these illnesses. Getting your COVID vaccine and boosters will help protect you from infection and will also provide your baby with antibodies through the placenta (and your breast milk, if you breastfeed).
Here are a few other things you can do to promote a healthy placenta and a healthy baby:
- Go to all your prenatal checkups and work with your healthcare provider to manage any health conditions, such as high blood pressure, which can cause problems with the placenta.
- Don't smoke or use drugs. Placental problems, like placental abruption, are more common in women who smoke, use illegal drugs (like cocaine and heroin), or abuse medications (like opioids).
Delivering the placenta
A few minutes after your baby is born, the placenta detaches from the wall of your uterus and is delivered through your vagina. This is called the "afterbirth."
You'll have a few contractions, but this stage of childbirth usually lasts only about five to 30 minutes and feels more like menstrual cramps than labor pains. (If you're having a c-section, your doctor will remove the placenta manually.)
If you want, and if you've made prior arrangements with your provider, you can save the placenta.
Some women believe that encapsulating and eating the placenta after birth helps them recover faster, though there's no scientific evidence to support this claim.
Also note that some experts think eating the placenta may be harmful, as there are potential risks, including infection and heavy metal contamination. Be sure to discuss this topic with your provider if it's something you're considering.
Learn more:
Placenta previa
Placenta accreta
Slideshow: Fetal development, week by week
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Baby's Palate, Food Memories Shaped Before Birth : NPR
Baby's Palate, Food Memories Shaped Before Birth Amniotic fluid and breast milk can be flavored by the food a mother eats. And memories of these flavors are formed before birth. That could result in preferences for these foods or odors for a lifetime.
Opinion
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Gretchen Cuda-Kroen
Baby's Palate And Food Memories Shaped Before Birth
Mothers might not realize that the tastes and flavors they savor while pregnant can influence their babies' palates later.
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Maggie Starbard/NPR
Want your child to love veggies? Start early. Very early. Research shows that what a woman eats during pregnancy not only nourishes her baby in the womb, but may shape food preferences later in life.
At 21 weeks after conception, a developing baby weighs about as much as a can of Coke — and he or she can taste it, too. Still in the womb, the growing baby gulps down several ounces of amniotic fluid daily. That fluid surrounding the baby is actually flavored by the foods and beverages the mother has eaten in the last few hours.
"Things like vanilla, carrot, garlic, anise, mint — these are some of the flavors that have been shown to be transmitted to amniotic fluid or mother's milk," says Julie Mennella, who studies taste in infants at the Monell Chemical Senses Center.
In fact, Mennella says there isn't a single flavor they have found that doesn't show up in utero. Her work has been published in the journal Pediatrics.
The Scent Of Amniotic Fluid
To determine if flavors are passed from the mother to the the baby via the amniotic fluid, researchers gave women garlic capsules or sugar capsules before taking a routine sample of their amniotic fluid — and then asked a panel of people to smell the samples.
"And it was easy," says Mennella. "They could pick out the samples easily from the women who ate garlic." The sense of taste is actually 90-percent smell, she added, so they knew just from the odor that the babies could taste it.
Mennella says she got the idea from dairy farmers, who in the 1960s and 70s were doing research on how the diet of the dairy cow impacted the flavor of the milk. She says cows that graze on wild garlic and onion, or who live in stinking barns, produce milk with distinct flavors.
But Mennella says that not only is the amniotic fluid and breast milk in humans flavored by food just like cows, but memories of these flavors are formed even before birth. That could result in preferences for these foods or odors for a lifetime. In other words, if you eat broccoli while you're pregnant, there's a much better chance your baby will like broccoli.
Mennella says this had already been observed in rabbits, so she decided to test it in human babies — with carrots. Pregnant women were divided into three groups. One group was asked to drink carrot juice every day during their pregnancy, another during breastfeeding and a third to avoid carrots completely. Then when the children began to eat solid food, researchers fed them cereal made either with water, or carrot juice and videotaped their responses.
Things like vanilla, carrot, garlic, anise, mint — these are some of the flavors that have been shown to be transmitted to amniotic fluid or mother's milk.
Julie Mennella, who studies taste in infants at the Monell Chemical Senses Center
Introducing Babies To Food Culture
"And just like the European rabbit, the babies who had experienced carrot in amniotic fluid or mother's milk ate more of the carrot-flavored cereal," says Mennella.
"And when we analyzed the video tapes they made less negative faces while eating it."
This makes a lot of evolutionary sense, says Mennella. Since mothers tend to feed their children what they eat themselves, it is nature's way of introducing babies to the foods and flavors that they are likely to encounter in their family and their culture.
"Each individual baby is having their own unique experience, it's changing from hour to hour, from day to day, from month to month," says Mennella. "As a stimulus it's providing so much information to that baby about who they are as a family and what are the foods their family enjoys and appreciates."
That very idea got Matty Lau thinking 'how is it that kids in other cultures eat foods that are spicy, bitter, or have pungent flavors?' She's a Chinese-American who had a baby in late July and recalls growing up eating foods most American kids she knows would never touch.
"My parents are great cooks — and so they'll cook things like preserved oysters.
I always wondered how it was that I was able to grow up eating bitter vegetables like kale and mustard greens and things like ginger," says Lau.
Instilling A Love Of Chinese Flavors Before Birth
While she was pregnant, she consciously tried to provide her baby with the flavors she loves from her native Chinese cuisine. She the hopes that when her baby is older, it will share her love of flavorful food.
"I was really concerned that my child enjoy food as much as the rest of my family," says Lau.
University of Florida taste researcher Linda Bartoshuk says babies are born with very few hard and fast taste preferences. She says Mennella's work shows that very early exposures to flavors – both before and after birth — make it more likely that children will accept a wide variety of flavors. And when those early exposures are reinforced over a lifetime, Bartoshuk thinks they might have far-reaching implications, even promoting good eating.
"To what extent can we make a baby eat a healthier diet by exposing it to all the right flavors — broccoli, carrots, lima beans, et cetera? Could we do that or not? My guess is we could," says Bartoshuk.
Menella acknowledges that many toddlers will still make a sour face when given broccoli, no matter how much the mother ate while pregnant. And maybe they will never like it. But she says parents should keep exposing young children to these flavors because they can eventually learn to like them.
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How the baby is fed in the womb
In the first two weeks after fertilization, while the egg has not yet had time to implant into the uterine wall and acquire the placenta, it receives nutrients from its thickened inner shell - the yolk sac.
From the fourth week, the embryo receives the oxygen and nutrients it needs through the chorionic villi, which then transforms into the placenta - a reliable home for the baby, which protects him, and is also the main organ that exchanges between mother and fetus. The placenta is also called the baby's place. This is a temporary organ that is formed and works only during pregnancy.
It is through the placenta that the baby communicates with the mother's body. From here, it receives proteins necessary for the structure of tissues, carbohydrates for energy and maintenance of the body, and fats, vitamins and minerals for proper metabolism. Through the placenta, the child also receives oxygen - without it, the body of the fetus cannot exist. All metabolic products are also excreted through the placenta. The placenta protects the child from infection, prevents immunological conflict between the foreign tissues of the mother and the child, and supplies both organisms with the hormones necessary for their development.
See also: How to restore breasts after pregnancy
its bones and soft tissues. The fetus developing in the uterus requires a certain amount of proteins, fats, carbohydrates, vitamins and minerals. All these substances enter the mother's body with food, are broken down in the digestive system to simple molecules and absorbed into the blood, which delivers all the vital components to the fetus.
The womb is a unique microsystem that protects the baby and constantly adapts to its changing needs. Mother and fetus organisms work in unison. Even a slight change in the level of one of the indicators of the composition of the child's blood instantly causes a compensatory reaction of the mother's body. This feedback guarantees the supply of all nutrients, vitamins and minerals necessary for the normal growth and development of the baby. At the same time, this ensures the removal of the waste products of the fetus from its body.
The fetus is connected to the mother's body through the placenta and vessels that form the umbilical cord. The umbilical cord is made up of two arteries and a vein, similar to a cord with several ropes, which are twisted together and covered with a sheath. This makes the umbilical cord extremely durable. The umbilical cord can twist and turn, and the force of blood flow in the arteries keeps it taut so your baby can't get tangled up in it. During pregnancy, the length and width of the umbilical cord increases with the growth of the fetus.
During pregnancy, the placenta also changes to meet the nutritional needs of the fetus. It controls the transfer of nutrients from mother to baby, as well as hormones and other substances. However, if the mother's diet is deficient in nutrients, the placenta will not be able to fully develop to provide the fetus with an effective supply. The low nutrient content of the mother's blood will permanently inhibit the normal functioning of the placenta. The placenta becomes unnecessary when the umbilical cord is cut - at this moment all the organs of the child begin to function independently.
Read also: Why shouldn't pregnant women wear heels?
The baby is able to extract from the mother's body some of the substances he needs, for example, most often this refers to calcium, which is washed out of the mother's bones if this mineral is absent in her diet. But his need for energy and nutrients is met in a different way. And if the mother suffers from malnutrition, the child will suffer with her.
If a mother is systematically malnourished, the placenta will not be able to fully develop to supply the developing baby with everything it needs. This, in turn, increases the risk of miscarriage and premature birth, as well as low birth weight in the newborn. It is necessary to take your pregnancy with all responsibility and make your diet complete and balanced.
Read Ivona.ua in Google News
How does a baby eat and breathe in the womb?
The very process of fertilization of an egg by a spermatozoon and then the further growth of the embryo into a child is a mystery and is not subject to the human mind.
One can speak at least a million times about the mechanism of pregnancy and childbirth, but it is still impossible to comprehend it: well, how can such a beautiful baby be obtained from two cells that are only visible under a microscope?
Secrets of intrauterine life
Indeed, trying to delve into the innermost nature is a thankless task.
But still, some features of the course of pregnancy and intrauterine development of a person can be tried to be explained.
Probably, many future parents have the following questions:
1) How does a baby eat in the womb?
2) How does the child breathe inside?
Let's try to lift the veil of secrecy and answer at least them.
A child inside the mother
It is natural that a child cannot and does not know how to eat on his own: all nutrients come to him through the mother's body, and at each stage of pregnancy the mechanism of this interaction is different. It is known that during the first weeks, a fertilized egg wanders around the uterus, looking for places to attach. At this time, the embryo receives nutrients only from those reserves that the egg itself has accumulated.
After the fixation of the egg, the connection between the unborn child and the mother's body is established, and it is from this moment that all nutrition begins to come from the mother.
It is during this period that the placenta begins to form, which will finally mature by about 14 weeks. The fetus still receives nutrients from the dwindling supply of the egg, but the need for nutrition grows more and more every day, and soon the already formed placenta takes over this role. It is through it that the growing fetus will receive all the substances necessary for development and weight gain.
The placenta is a very smart and necessary organ that communicates between the organisms of the mother and the unborn child.
The placenta and its functions
The placenta is thick villi that go deep into the uterus, through which the microelements and vitamins necessary for the baby are sucked out of the mother's body, and at the same time, the products of his vital activity are absorbed. In addition, this unique organ provides breathing to the child, also sucking up all the necessary amount of oxygen from the mother's blood and delivering it to the blood of the growing fetus.
