Pregnancy Week-by-Week

Ovulation occurs during Week 2 followed by fertilization during Week 3. Many women do not know that they are pregnant during this time. 

At Week 4, the baby is now officially an embryo! Your baby is the size of a poppyseed. Some women begin to experience symptoms, such as nausea, during Week 4.

At Week 5, your baby is the size of a peppercorn. At this stage, the baby begins to develop a brain, heart, spinal cord and blood vessels. Expect increased symptoms during Week 5, including breast tenderness and food aversions.

Week 6 is a time of great growth! Your baby is now the size of a pomegranate seed. The baby begins to develop the liver and kidneys. For some expectant mothers, the baby's heartbeat may be heard on ultrasound during this week.

Your baby continues to grow and now is the size of a blueberry! During Week 7, the baby's arm buds begin to develop. Symptoms such as frequent urination and breast sensitivity are common.

Week 8 and your baby is now the size of a kidney bean! The baby is now starting to form intestines, and the fingers and toes appear webbed. The baby is moving around - although you will not feel the movement for several more weeks.

Your baby is the size of a cherry during Week 9. The digestive tract and genitals have developed. The hands also continue to form.

At Week 10, your baby is the size of a kumquat. The eyes are now starting to develop. Clothes may begin to start feeling tight for mama-to-be.

Your baby is the size of a Brussels sprout at Week 11. During this week, the fingers and toes are separating. The baby will have tiny ears and fingernails. 

At Week 12, the baby is the size of a lime. The baby's skeletal structure has developed and the baby is now developing reflexes.

Your baby is the size of a pea pod at Week 13. At this stage, the baby continues to move around and may even begin sucking his or her thumb!

Week 14 and your baby is now the size of a lemon. The esophagus, larynx and vocal cords begin to develop during this week.

Your baby is the size of an apple at Week 15. The baby's scalp pattern is starting to develop.

At Week 16, your baby is the size of an avocado. The baby's muscles are growing stronger and you may even begin to feel the baby move!

Your baby is the size of a turnip at Week 17. The reproductive system begins to develop and the baby may start to have hiccups!

Week 18 and your baby is the size of a bell pepper. The baby's large intestine has developed. You may begin to feel stronger kicks now. 

Your baby is the size of an heirloom tomato at Week 19. There is increased sensory development. Mama-to-be may start to feel the pressure of the quickly growing baby. 

At Week 20, the baby is the size of a banana. The external genitalia has developed and may be visible on ultrasound. 

Your baby is as long as a carrot at Week 21. The baby continues to grow and move, and mama-to-be will likely be gaining weight. 

At Week 22, your baby is the size of a spaghetti squash. The baby is developing eyelids and eyebrows. 

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Your baby will be the size of a large mango at week 23. Your baby's hearing will have developed. 

At Week 24, your baby is the length of an ear of corn. The baby's blood vessels and organs are visible through translucent skin.

Your baby is the size of a head of rutabaga. The baby's brain is developing a complex structure. Mama-to-be may be experiencing discomfort from uterine stretching.

At Week 26, your baby is about the length of a scallion. Eyelids begin to open, and the baby starts to practice breathing. 

Your baby is the size of a cauliflower at 27 weeks. Your baby is starting to smile - especially when sleeping!

At Week 28, your baby is the size of an eggplant. Lungs start to develop, which helps circulate oxygen throughout the baby's blood vessels. 

Your baby is the size of a butternut squash by Week 29. The baby will gain weight, with subcutaneous fat developing.

At Week 30, your baby is the length of a large cabbage. The baby's bones start to harden this week. 

Your baby is the length of a coconut at Week 31. The baby is able to turn his or her head from side to side and continues to gain weight.

At Week 32, your baby is the size of a papaya. Your baby's skin will turn from see-through to opaque, and the organ are now fully developed. 

Your baby is the size of a pineapple at Week 33. Your baby is able to suck and swallow and continues to practice breathing skills. 

At Week 34, the baby is the size of a cantaloupe. The baby's optical structure is complete.

Your baby is the size of a honeydew melon at Week 35. Your baby's liver can process some waste products, and the kidneys are fully developed. 

At Week 36, your baby is the size of a head of romaine lettuce. The skull has not yet fused. The baby is gaining weight and is becoming less wrinkled.

Your baby is the size of a stalk of Swiss chard at Week 37. The baby continues to gain weight and may now have less room to move around!

At Week 38, your baby is about the length of a leek. Your baby's lungs have developed and the vocal cords have strengthened.

Your baby is the size of a mini watermelon at Week 39. The baby's lungs continue to develop. Mama-to-be may start to experience more contractions as she prepares for labor.

At Week 40, your baby is the size of a small pumpkin. Your baby's head has likely dropped, and you will soon welcome your little bundle of joy!