Womb milk nourishes human embryo during first weeks of pregnancy18:25 01 May 2015 by Andy Coghlan
Call it the milk of life – not breast milk, but womb milk. For the first 11 weeks of pregnancy, before the mother's nutrient-rich blood supply is plumbed in, all the materials and energy for building a baby are supplied by secretions from glands in the uterus lining.
For the first time, researchers have worked out in detail how nutrients make their way from these glands into the developing embryo. "It's like a rapidly growing building site," says John Aplin of the University of Manchester, UK.
During pregnancy, the lining of the uterus behaves quite differently to normal: the glands start storing large amounts of glucose as glycogen,
which is then secreted to nourish the embryo during its first 11 weeks.After this time, the mother's blood supply delivered via the umbilical cord takes over and the "womb-milk" secretions dry up. But how the glycogen and other materials for baby-building were transported to the embryo and placenta was a mystery until now.
Vital nutrientsTo investigate, Aplin and his colleagues examined womb, placenta and embryonic tissue donated by women who had chosen to terminate their pregnancies. The samples came from all stages of early pregnancy, so the researchers were able to analyse how they changed over time.
By using a staining dye, they were able to see wherever glycogen was present in the tissues. They found that it was abundant in the recesses of the womb lining, where it is broken down into smaller molecules. These molecules then diffuse into a cavity just outside the placenta, known as the intervillous space. From there, they are absorbed into the placenta.
"Once the sugar is there, some is used straight away as energy to help the embryo grow, and the rest is reconverted to the storage molecule, glycogen," says Aplin.
The team also tracked the transport of substances called glycoproteins. These are vital for growth because as well as containing sugar fragments, they contain protein that can be broken down into amino acids – the building blocks from which tissue is assembled.
Precarious stateAplin says that
in the first crucial weeks, womb milk is the embryo's only source of nourishment. This is no accident: at the beginning of a pregnancy, the placenta is much larger than the growing embryo, so the pressure of arterial blood would likely dislodge the embryo from the wall of the uterus. Only by 11 weeks or so is it big enough to withstand and accept its mother's blood.
Next, Aplin and his colleagues hope to investigate how a mother's diet and other factors, such as smoking, affect the build-up of glycogen in the womb lining. "It could be that these trigger settings in the embryo that affect the risk of obesity or diabetes in life," he says.
"The first few weeks of pregnancy is a critical phase for embryonic development," says Graham Burton of the University of Cambridge, whose team
discovered in 2002 that the uterus lining – not the mother's blood – nourishes the embryo.
[/color]"Our understanding has been revolutionised over the past decade by the discovery that nutrients are supplied by these glands in the uterus lining during the first trimester – the so-called 'uterine milk'," Burton says.
The latest research adds new insights into the enzymes that help deliver glucose across cell membranes to the embryo and placenta, he adds.
Journal reference: Placenta, DOI: 10.1016/j.placenta.2015.01.002
http://www.newscientist.com/article/dn27460-womb-milk-nourishes-human-embryo-during-first-weeks-of-pregnancy.html#.VUZzBWctHm4Agelbert NOTE: So, the FACT that what goes on in the first 11 weeks to keep the fetus alive is NOT an accident, but a very deliberate REQUIREMENT involving placental growth biochemical math, means, uh, WHAT, exactly?
I did a term paper on what that means in zoology before all the above was known. The point I made to the class, a point that had the female pre-med students squirming
, is that BOTH the fetus AND the placenta are NOT part of the female bearing the new life form. In fact, the new life form is a type of parasite.
WHY? Because, even in 1986, it had been clearly established, by studies of pregnant mammals (of several species, not just humans), that the pulmonary (gas exchange), hepatic nutrient uptake and renal waste disposal functions of the placental fetal life support system WILL successfully attack the host pregnant female for the benefit of the embryo.
IOW, bone loss and malnutrition effects will manifest in the pregnant female long before the fetus is affected simply because the placental machinery (
tiny fingers in the in va gin ated arterial blood vessels surrounding the uterus) gets whatever it needs, even to the point of demineralizing host bones.
It's ALL business. That business is the clear priority of the placenta to keep the fetus alive and growing over the health of the host. It is the placenta, not the pregnant females' endocrine system, that sends the biochemical signals to get her mammary glands to produce milk at a certain point in the pregnancy. It is the placenta that keeps the pregnant female's immune system from attacking the "parasite" feeding off of her by some clever biochemical tricks to fool the host into thinking the fetus is not a separate entity.
The critter in there is NOT a part of the female host FROM THE START. It is HUMAN and it is separate and it has a placental space suit to take care of BUSINESS. The host CAN, of course, kill the tiny human with modern technology. The fetus is a parasite and will tax the health of the host if said host cannot get proper nutrition. In fact, there are many species of mammals that cannot get pregnant UNLESS they have a certain level of nutrition. I'm sure TPTB are
working on applying that to the "useless eater" humans out there
. But there is NO WAY anybody can claim scientifically that the fetus is a "part" of the body of the host.
The above new scientific discovery just underlines the fact that, ALREADY in the first 11 weeks, the human embryo/fetus is an individual, separate from the mother.