How Does A Baby Grow in The Womb In 9 Months?

Being a mother is far from an easy task. From fertilization to the final delivery of the baby and beyond, the road of pregnancy and motherhood is a difficult one, both emotionally and biologically. Let’s look at this 9-month journey of pregnancy and understand a bit more what every mother actually goes through to bring a child into the world.

Fertilization: We were only cells in the beginning. Cells that were formed when our father’s sperm fertilized our mother’s egg. Fertilization takes place in a female’s Fallopian tube, which connects the uterus (womb) with the ovary.


The mother’s egg and the father’s sperm cells contain only 23 chromosomes each, which allows for them to be added together at fertilization. When combined together, they make one completely new cell – the human embryo, zygote or conceptus – with 46 chromosomes, which carries a fresh, unique combination of genes.

Implantation: Implantation usually happens around 6-12 days after fertilization. The fertilized egg has now completed its journey through the Fallopian tube and becomes attached to the lining of the uterus.

700px-Week1_summaryAt the end of the 4 weeks following fertilization, the nervous system, spinal cord, liver, and kidneys start taking shape.

From the 5th week on, eyes, legs and hands begin to develop. In the 6th week, fingernails start forming, and the mouth and lips become present.

At the end of 8 weeks, a baby’s bones, nose, eyelids, and toes start appearing and most of the organs are in place. Embryos have even been found to respond to touch at this stage.

Over the next month, teeth begin to form. The baby can turn its head, hiccup and begin exploring its limited range of movement. The circulatory system starts to work and a skeletal structure is definitely present. The baby can feel certain things, including pain. The vocal cords are present and almost all the systems are in place and functioning.


Baby at 12 weeks

By the next month, the baby has developed taste buds and is pumping several quarts of blood every day. It can also suck its thumb!

By the end of 5 months, the baby measures 140mm, just over one-third of the size it will be at full term, and weighs around 200g. The heart now starts pumping quite a lot of blood, almost 30 liters each day. The baby shows sensitivity to light and responds to sound. The pregnancy begins to show externally as the uterus expands and changes shape to accommodate the growing baby.

At the end of 6 months, the baby practices breathing by inhaling the amniotic fluid into its developing lungs. The mother also begins to feel the baby kicking or will feel the hiccups that an unborn baby often gets after drinking the amniotic fluid or while practising breathing. The oil and sweat glands of the baby start functioning.

7 months and beyond:  The baby can now open and close its eyes, and the fetus starts using four senses (out of five). These are vision, hearing, taste, and touch. Its skin thickens considerably and a layer of fat develops beneath the skin of the baby. The weight of the baby also increases gradually. Now, the baby can identify the difference between waking and sleeping, and can relate to the moods of the mother. The baby’s heart becomes quite mighty and is able to pump 300 gallons of blood per day, preparing for the eventual release from the womb!

stages-of-fetal-developmentImage Source

Delivery: The baby is finally ready to enter the world. The baby is positioned upside down, with its head facing downwards, as the head is usually the first part that emerges during childbirth. The cervix gradually opens to allow the baby to pass into the vagina, and from there, the baby is born!

Needless to say, a mother goes through a lot over this period of 9 months, not to mention a lifetime of worries and challenges as a mother. There are ups and downs on this pregnancy path where a mother must stay strong while undergoing many physical and mental challenges just to usher a new life into the world. Therefore, how about a round of applause for mothers all over the world and give yours the thanks she deserves, as well as a big hug!

The entire journey of motherhood is a tremendous one, yet mothers selflessly take it in a beautiful way. Below is a video that shows some common, yet amazing, facts about pregnancy:

Suggested Reading

For more detailed information on fetal development, follow the links provided below:

  1. University of Maryland Research Paper
  2. Wikipedia
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About the Author:

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

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