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It starts with first day of your menstrual cycle. In this period, conception does not occur, but your uterus is getting prepared for fertilization.

Your uterus is abundant with blood tissue and your eggs are maturing in one of your ovaries and getting ready to release one. From the day of your menstrual period, around fourteen to sixteen days, ovulation takes place (for a 28-day menstrual cycle period).

The sperm penetrates the egg in the fallopian tube. Although many sperms meet the egg, only one sperm enters your ovum and fertilization takes place.

After the ‘blastocyte’ enters the uterus, it will settle in one spot of your uterus. Now, these cells split into two groups; one that forms the placenta and the other that forms the baby.

The embryo develops in layers, ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer).

Your baby is 1/17 of an inch long. This is the rapid growing week. In this week, your baby starts to have heart beating and the arms and legs will be formed along with some other organs.

Development of arms and legs continue. The size of your baby is 1/3 of inch. The other organs like brain, intestine, nostrils, lenses will also grow.

Your baby will start to have fluttering heartbeat, fingers start to develop, leg buds starts to show feet, face appears to change with ears, eyes, and tip of nose, and the intestine start to develop.

Almost all organs will develop. In the eleventh week, the baby is called as fetus. In this week, the baby is about two inches. Fingers and toes will be separated and hair starts to grow. Peristalsis and contractions take place in intestine.

The baby starts to practice inhalation and exhalation. In thesixteenth week, baby’s sex can be identified.

The ‘Vernix’ starts to develop to protect the skin of your baby from amniotic fluid. The baby reaches nearly a pounds weight.

The spine starts to develop, lungs begin to secrete, and the baby can open eyelids. The baby weighs around 2 pounds.

The eyes are completely formed and hair grows. The baby can recognize your voice. Reproductive organs will also be formed. The baby weighs four pounds in this month. Fat continues to accumulate. Almost all organs develop during this month.

In this month, the baby weighs around 4 pounds and has a height of 19 inches. The baby takes more space inside the uterus and now there will be less space for the baby to move freely. The Baby's skin will have many layers of fat now and the layers of fat will keep on increasing in the days to come.

The ‘Vernix’ disappears and the baby cannot move. Now, you are about to deliver your baby. The little one is going to be out in this world.