Keeping Track of Fetal Development Month by Month

My Baby Is the Size of An Apple Seed

During the first month of pregnancy, you may not know that you're pregnant at all. While this is the "first" month, pregnancy is actually closer to ten months if you measure from the pregnant person's last period. 

During the first month, your fetus is growing rapidly. While it starts as a small collection of cells bundled together, it soon grows to the size of a poppy seed. 

These early stages of baby development move fast, so by the end of the month, your fetus will be around the size of a small apple seed. 

The embryo, at this point, will be unrecognizable as a human. It may have a primitive-looking face and it will develop a heartbeat by the end of the month (though it's too faint to hear). 

My Baby Is the Size of A Kidney Bean

During month two, your baby starts solidifying. Cartilage starts to turn into bone and the nervous system becomes more complete. While embryos aren't aware at this age, they do have sensory organs and a neural tube. 

Like all embryos, your baby will have a larger head than its body. This is also the earliest point that a doctor may be able to detect signs of your baby's heartbeat. 

At the end of this month, your embryo will become a fetus. Your fetus will be about one inch long.

My Baby Is the Size of A Lime

Month number three is the last month of your first trimester. This is an exciting time, and it's often when people start sharing their pregnancy announcements with others. At the end of the third month, the risk of miscarriage drops. 

This is when a fetus starts to resemble an actual baby. That said, it's tiny and mostly unrecognizable as a human. At this point, your baby should have defined fingers, toes, and limbs, and they may start to grow fingernails.

Your baby will start to develop reproductive organs at this time, but it's too early for doctors to determine the biological sex of the baby.

By the end of the month, your baby will have most of its early development stages behind them. They will have all of their limbs, organs, and internal systems. They may even start to move.

My Baby Is the Size of An Avocado

At month four, you've moved into your second trimester. By this point, the worst part of your morning sickness and soreness should be behind you. 

At this point, your baby starts developing defined facial features. Your baby may yawn and suck its thumb, though these aren't conscious actions. 

At this point, your doctor should be able to detect your baby's heartbeat on a doppler. While your baby has well-formed reproductive organs at this point, it may or may not be too early for an ultrasound or scan to detect them.

Your baby's nervous system starts to function at this point and it's starting to develop hair. This is an exciting month! 

My Baby Is the Size of A Banana

You're more than halfway through your pregnancy. Exciting!

During this stage of baby development, you will almost definitely be able to determine the biological sex of the baby as long as its placement is appropriate. 

This is where you may first feel your baby move. That early movement is referred to as the "quickening." It happens because your baby is starting to use its muscles. 

Your baby will develop more hair on its head and a fine coating of hair on its body. This isn't the hair that will stay with the baby. It should disappear soon after the baby is born.

This is also when your baby will develop a protective coating called vernix caseosa. Amniotic fluid may be too harsh for the baby's skin long-term, and this coating helps to protect them. It also protects their fragile skin from the world after they're born.

Your baby, at this point, could weigh as much as a pound!

My Baby Is the Size of A Mango

This is the final month of your second trimester. The end is right around the corner, but your baby still needs more time to finish developing.

Your baby has fingerprints and toe prints now! It also has a wrinkly and red layer of skin that's getting ready to enter the world. Your baby also may be able to open its eyes at this point. 

Your baby can hiccup at this point, and you'll be able to feel it. It can also hear and feel disturbances in the parent's body, like movement or noise. Your baby will be very active at this point.

This is also the first point in which your baby may survive if you were to go into early labour (though it would require intensive medical care). This means that your baby is starting to stabilize and be more independent. 

My Baby Is the Size of An Eggplant

The first month of the third trimester is exciting (though some people consider this a part of the second trimester). At seven months, your baby is taking up a lot of space. It's accumulating more body fat so it's ready to come into the world. 

While your baby is only two to four pounds at this point, it's likely that it will survive a premature birth. It's at a point where it can respond to sound, light, and even pain or discomfort. 

My Baby Is the Size of A Pineapple

As you round the corner of the eighth month, you're probably getting nervous (and tired). At this point, the baby feels quite heavy. It can weigh up to five pounds. 

Your baby will be able to see and hear, and it will continue responding to those stimuli. It will be more active in this stage as its muscles strengthen and the baby learns to use them. 

Your baby will have well-developed internal organs, but they won't all be ready to greet the outside world yet. While your baby can survive outside of the womb, it won't have fully developed lungs.

These babies often still need to be under intensive care or even in incubators for a brief period after birth. 

My Baby Is the Size of A Small Watermelon

This is the ending stretch of developmental stages. When we say nine months, it also includes that bonus "tenth month" from the earlier conception starting point. 

At this point, your baby has strong reflexes. The lungs are developed enough for the baby to breathe outside of the womb. The baby will be able to turn its head and make deliberate movements (and it will do so often). 

During the last few weeks of pregnancy, labour can happen at any time. It often happens at 40 weeks, but it can start anywhere between weeks 37 and 40. During this time, the parent's cervix will start to dilate. 

Your baby should change position to prepare for birth. As long as everything goes to plan, it should have its head positioned downwards.

Make sure to check with your doctor during these last few weeks to make sure that the baby is in the correct position. If it isn't, you may need an alternative birth (such as a C-section). Get ready to meet your baby and prepare for all things related to raising a child.