When does baby feed off mother

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.)

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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:

  1. When you eat, the food travels to your stomach, where it's broken down (digested) into glucose, fats, vitamins, minerals, and protein.
  2. The nutrients are absorbed into your bloodstream and travel to the placenta.
  3. 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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Breastfeeding FAQs: How Much and How Often (for Parents)

Breastfeeding is a natural thing to do, but it still comes with its fair share of questions. Here's what you need to know about how often and how long to breastfeed your baby.

How Often Should I Breastfeed?

Newborn babies should breastfeed 8–12 times per day for about the first month. Breast milk is easily digested, so newborns are hungry often. Frequent feedings helps stimulate your milk production during the first few weeks.

By the time your baby is 1–2 months old, he or she probably will nurse 7–9 times a day.

In the first few weeks of life, breastfeeding should be "on demand" (when your baby is hungry), which is about every 1-1/2 to 3 hours. As newborns get older, they'll nurse less often, and may have a more predictable schedule. Some might feed every 90 minutes, whereas others might go 2–3 hours between feedings.

Newborns should not go more than about 4 hours without feeding, even overnight.

How Do I Count the Time Between Feedings?

Count the length of time between feedings from the time your baby begins to nurse (rather than at the end) to when your little one starts nursing again. In other words, when your doctor asks how often your baby is feeding, you can say "about every 2 hours" if your first feeding started at 6 a.m., the next feeding was around 8 a.m., then 10 a.m., and so on.

Especially at first, you might feel like you're nursing around the clock, which is normal. Soon enough, your baby will go longer between feedings.

How Long Does Nursing Take?

Newborns may nurse for up to 20 minutes or longer on one or both breasts. As babies get older and more skilled at breastfeeding, they may take about 5–10 minutes on each side.

How long it takes to breastfeed depends on you, your baby, and other things, such as whether:

  • your milk supply has come in (this usually happens 2–5 days after birth)
  • your let-down reflex (which causes milk to flow from the nipple) happens right away or after a few minutes into a feeding
  • your milk flow is slow or fast
  • the baby has a good latch, taking in as much as possible of your areola (the dark circle of skin around your nipple)
  • your baby begins gulping right away or takes it slow
  • your baby is sleepy or distracted

Call your doctor if you're worried that your baby's feedings seem too short or too long.

When Should I Alternate Breasts?

Alternate breasts and try to give each one the same amount of nursing time throughout the day. This helps to keep up your milk supply in both breasts and prevents painful engorgement (when your breasts overfill with milk).

You may switch breasts in the middle of each feeding and then alternate which breast you offer first for each feeding. Can't remember where your baby last nursed? It can help to attach a reminder — like a safety pin or small ribbon — to your bra strap so you'll know which breast your baby last nursed on. Then, start with that breast at the next feeding. Or, keep a notebook handy or use a breastfeeding app to keep track of how your baby feeds.

Your baby may like switching breasts at each feeding or prefer to nurse just on one side. If so, then offer the other breast at the next feeding. Do whatever works best and is the most comfortable for you and your baby.

How Often Should I Burp My Baby During Feedings?

After your baby finishes on one side, try burping before switching breasts. Sometimes, the movement alone can be enough to cause a baby to burp.

Some infants need more burping, others less, and it can vary from feeding to feeding.

If your baby spits up a lot, try burping more often. While it's normal for infants to "spit up" a small amount after eating or during burping, a baby should not vomit after feeding. If your baby throws up all or most of a feeding, there could be a problem that needs medical care. If you're worried that your baby is spitting up too much, call your doctor.

Why Is My Baby Hungrier Than Usual?

When babies go through a period of rapid growth (called a growth spurt), they want to eat more than usual. These can happen at any time. But in the early months, growth spurts often happen when a baby is:

  • 7–14 days old
  • 2 months old
  • 4 months old
  • 6 months old

During these times and whenever your baby seems extra hungry, follow your little one's hunger cues. You may need to breastfeed more often for a while.

How Long Should I Breastfeed My Baby?

That's a personal choice. Experts recommend that babies be breastfed exclusively (without formula, water, juice, non–breast milk, or food) for the first 6 months. Then, breastfeeding can continue until 12 months (and beyond) if it's working for you and your baby.

Breastfeeding has many benefits for mom and baby both. Studies show that breastfeeding can lessen a baby's chances of diarrhea, ear infections, and bacterial meningitis, or make symptoms less severe. Breastfeeding also may protect children from sudden infant death syndrome (SIDS), diabetes, obesity, and asthma.

For moms, breastfeeding burns calories and helps shrink the uterus. In fact, breastfeeding moms might return to their pre–pregnancy shape and weight quicker. Breastfeeding also helps lower a woman's risk of diseases like:

  • breast cancer
  • high blood pressure
  • diabetes
  • heart disease

It also might help protect moms from uterine cancer and ovarian cancer.


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What does the baby do while it is in the mother's belly

17 August 2018

In 9 months, a child goes a long way from a tiny embryo to a chubby baby and already in the womb acquires some features that will stay with him for life: for example, you can understand whether he will become right-handed or left-handed and what kind of food will prefer. In a fairly short period of time, a lot of interesting things happen to a child, and today we invite you to go through the path from birth to birth with your baby.

1st trimester of pregnancy
1st–2nd week

So the long journey began. For the first 4 days, the future person is smaller than a grain of salt - its size is only 0.14 mm. However, starting from the 5th day, it begins to grow and by the 6th it almost doubles - up to as much as 0.2 mm. On the 4th day, the embryo "comes" to where it will spend the next 9 months - into the uterus, and on the 8th day it is implanted in its wall.

3rd–4th week


Embryo at the 4th week of pregnancy.

Around the 20th day of pregnancy, a very important event occurs: the neural tube appears, which will then turn into the spinal cord and brain of the child. Already on the 21st day, his heart begins to beat and all important organs, such as the kidneys and liver, begin to form. The eyes have not yet taken their usual position - the bubbles from which they will then take shape are located on the sides of the head. By the end of the 1st month, the embryo has a circulatory system, and the spine and muscles begin to develop. nine0120

5th–6th week

© EDITORIAL USE ONLY/East News © lunar caustic/wikimedia

At the 5th week, the hands appear in the embryo, however, the fingers are still very difficult to distinguish, but in the joints the arms and legs are already bent. It was at this time that the external genitalia begin to form, but it is not yet possible to see on an ultrasound whether it is a boy or a girl. By the way, since its appearance, the embryo has grown a lot - it has increased by as much as 10 thousand times. Already now, the baby's face is beginning to form, and the eyes, which will be closed for a very long time, darken, becoming more human-like. nine0120

7th–8th week

The 7th week of pregnancy is the time when the baby begins to move, however, so far completely unnoticed by the mother, and the fingers and toes become almost the same as in adults. At this stage, the rudiments of milk teeth appear in the embryo and the reproductive system develops, and the kidneys begin to produce urine. Despite the fact that the growth of the fetus is only 2.5 cm, it acquires its own facial expressions, it has eyelids, and the tip of the nose becomes more defined. nine0120

9-10 weeks

© lunarcaustic/wikimedia

Baby at 9-10 weeks of gestation.

By this time, the baby has already grown well - its weight is 4 grams, and its height is 2-3 cm. Despite its tiny size, the brain is already divided into two hemispheres, and milk teeth and taste buds are beginning to form. The baby's tail and membranes between the fingers on the hands disappear, he begins to swim in the amniotic fluid and move even more actively, although still unnoticed by the mother. It was at this time that the child's individual facial features appear, and hair begins to grow on the head. nine0120

11–12 weeks

At this time, the genital organs are formed in the child, so it is already possible to find out his sex on an ultrasound scan, although the probability of an error is still high. The child still looks a little alien: he has a big head and a small body, but his face is more and more like an adult. The ears are almost in the right position, eyebrows and eyelashes appear. The cartilage that makes up the skeleton gradually ossifies, new blood vessels appear, and hormone production begins. By the way, the baby has already grown up to 6 cm and weighs about 20 grams. nine0120

13-14 weeks

Baby at 14 weeks pregnant.

Despite the fact that the child's head is half the length of the entire body, the face is more and more reminiscent of an adult, and the rudiments of all 20 milk teeth have already been formed in the oral cavity. The child is already able to put his finger in his mouth, but he will learn to suck a little later. Due to the active formation of blood vessels, the baby's skin is red and very thin, so vellus hair appears on the body - lanugo, which is necessary to maintain a special lubricant that protects against hypothermia. nine0120

2nd trimester of pregnancy
15th–16th week

By the 15th week, the baby has grown to 10 cm and is gaining weight - now he weighs about 70 grams. Despite the fact that the eyes are still quite low, the face is already quite recognizable, moreover, the child begins to “make faces”, since the facial muscles are well developed. By this time, he already knows how to suck his thumb, and the sebaceous and sweat glands begin their work.

17th–18th week nine0120

And finally, the child's auditory canals are formed, so he begins to distinguish sounds well and hears the mother's voice, moreover, he is able to recognize it. In addition to the milk teeth, the embryos of the molars also appear, the bones are finally formed and begin to harden. By the way, the bones of the skull will remain mobile until birth - when passing through the birth canal, they will overlap each other to make it easier for the baby to be born. But the mother is finally beginning to feel the movements of the child, who has grown to 14 cm and 190 grams.

19-20 weeks

Baby at 20 weeks pregnant.

Despite the fact that the child's eyes are still closed, he is already well oriented in the surrounding space. Moreover, now you can understand whether the child will be right-handed or left-handed, because right now he begins to use his dominant hand more actively. Fingerprints appear on the baby's fingers - another unique sign of each of us. By the way, the child is already beginning to gradually distinguish day from night and is active at a certain time. nine0120

21–22 weeks

The 21st week is the time when the baby begins to gain weight due to the formation of subcutaneous fat. Soon, the folds that newborns have will appear on his arms and legs. On the 22nd week, those neurons are formed in the brain that will be with a person all his life. Very soon the child will open his eyes, he is already trying to do this, and the eyeballs move almost like an adult.

23–24 weeks

At 23 weeks, the baby may begin to dream, and his face is so formed that an ultrasound can determine whose facial features he has inherited. His skin becomes opaque, his eyes open, and the child can already react to light, moreover, bright flashes can scare him. By the 24th week, the baby grows to almost 30 cm, and its weight reaches 0.5 kg.

25th–26th week

At this time, the taste buds of the child are finally formed and, tasting the amniotic fluid, he can frown if he does not like it. By the way, this is how eating habits are formed - already in the womb we have our favorite and unloved foods. Very soon the child will learn to blink and can already see a little, however, so far it is very, very vague. nine0120

3rd trimester of pregnancy
27th–28th week

Baby at 27–28 weeks of gestation.

If you do an ultrasound at this time, you can see how the baby smiles and sucks his thumb intensively. At this time, the baby has the first "toy" - his own umbilical cord, and he actively studies his body. At the end of the 7th month of pregnancy, the child develops an individual metabolism, which he will have all his life. The baby is already quite large - his weight reaches 1.2 kg, and his height is 35 cm.

29th–30th week

© East News

Baby at 30 weeks pregnant.

The layer of subcutaneous fat is increasing, and the baby is becoming more and more plump and well-fed. In addition, he already knows how to cry, cough, and even sometimes hiccups - this happens, most likely, when he swallows too much amniotic fluid. By the 30th week, the baby's brain is already so developed that it is quite capable of remembering and even analyzing information. nine0120

31–32 weeks

At this time, a person has all 5 senses, and his daily routine is more and more reminiscent of the one he will follow after birth. The child hears the work of all the organs of the mother, knows her voice perfectly, thanks to which, immediately after birth, he is able to distinguish her from all other people. The baby's immune system begins to produce antibodies that will protect him from all kinds of infections that may lie in wait in the first days and months after birth. nine0120

33–34th week

And finally, subcutaneous fat is already formed, and lanugo disappears from the body of the fetus. By this time, the baby has grown a lot - the length of his body reaches 40 cm, and the weight is very close to or even exceeds 2 kg. The baby's nervous system is already fully formed, but the lungs are still developing.

35th–36th week

© East News

A child yawns. 3D ultrasound at 36 weeks pregnant. nine0120

At this time, the child looks almost exactly the same as when he was born. He is still quite thin, but the layer of subcutaneous fat is increasing more and more intensively. However, his hair and nails are already fully developed, and he himself becomes so big that he has almost no room to maneuver, so he can move less than in earlier stages.

37–38th week

And finally, the process of forming a person has finally ended - now he is completely ready for birth, and obstetricians consider the pregnancy to be full-term. Lanugo completely disappears from his body and can only sometimes remain on his arms and legs. Since there is almost no space left in the uterus, it may seem to the mother that the child has begun to move more intensively, but in fact the force of the blows has increased, because the child's muscles have already completely formed and strengthened. nine0120

39-40 weeks

© depositphotos.com

The first minutes after birth.

The lungs of a child continue to form until the very birth, and only at the time of birth they release the right amount of surfactant - a substance that prevents the alveoli from sticking together after the first independent breath.

Learn more