Nestled comfortably in the womb, your baby is constantly growing and changing. You may not even realize you’re pregnant until a few weeks in, but life is forming. This is the beginning of it all. Your egg becomes fertilized and life begins to form quickly. Cells start dividing and the groundwork of your pregnancy and baby’s formation begins.

The first trimester

Weeks 0 to 13: the first trimester is by far the most crucial of the three. This is when internal organs begin to form and the structure of the baby starts to form. This is also of course when the pregnancy symptoms kick in. Pregnancy symptoms can vary since every woman is different; some women get a boost of energy and others become tired during the first trimester. You can also begin to experience nausea, breast tenderness, and frequent urination. Let’s look into a deep breakdown and see what happens during the upcoming weeks of development.

Week 1 through 6: a lot begins to happen here. The groundwork of your placenta forms in week 3 and in week 4 the embryo forms. Once you get to week 5, the neural tube forms, which is the beginning framework of the baby’s spine and brain. When week 6 arrives, a lot starts to form. We can see the optic vessels begin, which leads to the forming of the eyes and ears. In addition, the beginnings of the digestive system form and buds form that will eventually become legs and arms.

Week 7 through 13: in week 7 hands begin to finally form, but they will look a little more like fins or little paddles. By week 8 fingers and toes begin to form but the toes and fingers haven’t separated just yet. The retinas in their eyes begin to form and intestines grow in length. Also during this week the genitals begin to form although the baby’s gender can’t yet be determined. In week 9 your baby has a small tail at the bottom of the spinal cord, this tail begins to shrink and the head begins to increase in size. The tip of the nose begins to grow and the baby begins to grow either testes or ovaries. Some movements may begin as well, but nothing that you will be able to feel. By the time that week 10 arrives, all vital organs have formed. Tooth buds start developing in the mouth and, if it is a male, testosterone will begin to produce. With the arrival of 11 weeks, the embryo becomes a fetus and begins to have distinguishing features you can see on your ultrasound.

Second trimester

Weeks 14 to 26: things really start to develop with the baby during the second trimester. This is when the pregnancy symptoms typically begin to calm down and you start to feel better when it comes to nausea and fatigue. Your belly begins to grow and many pregnant women begin buying maternity clothes. You may start to experience a rise in appetite and begin to experience leg cramps accompanied by heartburn.

Week 14 through 20: between week 14 to 20 the genitals are fully developed. Some hair will begin to grow but not much. What will occur is a lot of movement. Nothing you may feel, but he or she will be wiggling. By week 16 the baby will be smiling and able to keep their head up. During the 18th week, the baby will be able to see any bright lights directed at the belly. Speaking of bellies, the baby will continue to form fat so that he or she can maintain warmth at birth; this will continue throughout the rest of the pregnancy.

Week 20 through 26: Now that we are in the 20th week the baby will continue to grow more hair and form fingernails and toenails. When the 26th week arrives the baby will be able to feel touch and may start rubbing their face and hands. Your baby will also have a sense of balance and will now know when they’re upside down or upright in the belly.

The third trimester

Weeks 27 to 40: by week 27 the baby will look very similar, if not the exact same, as he or she will look at birth. While your child is in your womb, they will be able to hear and recognize your voice and get comfortable with other voices that they may hear on a daily basis. The baby will begin to transition from small movements to strong movements and jabs by week 29. Once you hit week 32 your baby will have their eyebrows, eyelashes, and hair on their head. By the 36th week your baby will be fully grown, ready and waiting to meet you.

The finish line

We have now made it to the final trimester. Constantly getting up at three in the morning to pee or clinging to the toilet in the mornings may be driving you crazy, but you know it’s all been worth it. You’re probably getting ready for baby showers and gender reveals, adding the finishing touches to your baby room, or taking it easy while your neck deep in baby books and or going to birthing and parenting classes. Either way, this is your time to get ready to meet your baby!