What is Placenta

Placenta occupies a unique position among the endocrine glands and play a major role in endocrinology of pregnancy. The placenta has been recognized as a source of various biological active peptides which play important role in maintainace of pregnancy and in maternal homeostasis during pregnancy.

The word placenta comes from the Latin for cake, from Greek “flat, slab-like”  in reference to its round, flat appearance in humans

The placenta is an organ that attached to the lining of mother’s womb during pregnancy  that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination,

The placenta is linked to baby by the umbilical cord. Unborn fetus is inside a bag of fluid called the amniotic sac, which is made of membranes.  Now what is umbilical cord and amniotic sac?

What is the amniotic sac?

The amniotic sac is a bag of fluid inside a woman’s womb (uterus) where the unborn baby develops and grows. It’s sometimes called the ‘membranes’, because the sac is made of two membranes called the amnion and thechorion.

Umbilical cord:

In placental mammals, the umbilical cord (also called the birth cord or funiculus umbilicalis) is the connecting cord from the developing  fetus to the placenta. During prenatal development, the umbilical cord is physiologically and genetically part of the fetus and (in humans) normally contains two arteries (the umbilical arteries) and one vein (the umbilical vein. The umbilical vein supplies the fetus with oxygenated, nutrient-richblood from the placenta. Conversely, the fetal heart pumps deoxygenated, nutrient-depleted blood through the umbilical arteries back to the placenta.

Steps during Synthesis  of placenta:

Ø  Trophoblast: The outermost layer of cells of the blastocyst that attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo. Also calledtrophoderm.

Ø  If a sperm penetrates the egg, fertilization results. Tiny hairlike cilia lining the fallopian tube propel the fertilized egg (zygote) through the tube toward the uterus. The cells of the zygote divide repeatedly as the zygote moves down the fallopian tube. The zygote enters the uterus in 3 to 5 days.

Ø  In the uterus, the cells continue to divide, becoming a hollow ball of cells called ablastocyst. If fertilization does not occur, the egg degenerates and passes through the uterus with the next menstrual period.

Ø  But if egg is fertilized then Between 5 and 8 days after fertilization, the blastocyst attaches to the lining of the uterus, usually near the top. This process, called implantation, is completed by day 9 or 10.