How big is baby?

Your baby is now around the size of a poppy seed! During week 3, the lucky sperm meets the egg, and conception occurs. The zygote travels for six days through your fallopian tubes, dividing and redividing into identical cells as it travels to the uterus. In week 4, now in your womb, the ball of cells (called the 'blastocyst') splits in two, becoming the embryo and the placenta. The amniotic sac and fluid are forming around your baby, and will act as a protective cushion until delivery.

Your baby is now around the size of an apple seed, or about 0.33cm (0.13 inches). Your embryo (which looks a bit like a tadpole at this stage) is starting to form major organs (kidney, liver, stomach and heart) and digestive, nervous and circulatory systems. Your body's recognition of the presence of a baby in your uterus triggers production of hCG (the hormone detected by pregnancy tests), which triggers production of other hormones like estrogen and progesterone. These hormones in turn trigger the pregnancy symptoms you've probably been noticing!

Your sweet pea is now around the size of, well, a sweet pea or about 0.65cm (a quarter of an inch). Now accelerating growth, your baby is starting to grow eyes, ears, nose, cheeks and chin. His or her little webbed hands and feet are starting to move, the heart is beating (fast), and blood is starting to circulate.

Your baby is now around the size of a blueberry, or about 1.3cm (about half an inch). Your baby's brain is growing fast, generating about 6,000 new cells every hour.  Arms and legs are emerging as joints start to form, and a permanent pair of kidneys is now in place!

Your baby is now around the size of a raspberry, or about 1.6cm (0.6 of an inch), and weighs in at a cool 1 gramme (0.04oz). Your baby is growing really fast, growing about a millimetre every day and continuing to straighten out in the trunk. Though you can't feel it yet, your baby is wiggling those little arms, legs and fingers and toes!

Your baby is now around the size of an olive, or about 2.3cm (0.9 of an inch), weighing in at nearly 2 grammes (0.07oz). Your embryo has now officially become a foetus. An ultrasound might at this stage be able to pick up a heartbeat! Your baby is starting to take a recognisable form of a baby as he or she adds distinct facial features!

Your baby is now around the size of a prune, or about 3cm (1.2 inches), weighing in at around 4 grammes (0.14oz). With bones and cartilage forming and vital organs beginning to function, your baby is making major progress. Body length is starting to increase rapidly, and arm joints are now working!

Your baby is now around the size of a lime or about 4cm (1.6 inches), weighing in at 7 whole grammes (0.25oz). Your baby has skin so transparent that blood vessels show right through, and the head is still as big as the body. Fingers and toes have lost their webbing, and nail beds, tooth buds and hair follicles are forming.

Your baby is now around the size of a plum, or about 5.3cm (2.1 inches), weighing in at 14 grammes (0.5oz). As you begin your second trimester, your baby's growth is focussed growth and maturation - almost all of baby's bodily systems are fully formed!

Your baby is now around the size of a peach, or about 7.3cm (2.9 inches), weighing in at 23 grammes (0.81oz). Your baby is now forming teeth and vocal cords, and your baby's proportions are now approaching normal with the head around one third the size of the body. Your baby's intestines are moving from the umbilical cord to the tummy.

Your baby is now around the size of a lemon, or about 8.6cm (3.4 inches), weighing in at 42 grammes (1.5oz). Your baby is keeping busy with such activities as thumb sucking and wiggling toes and fingers. Your baby is 'breathing' amniotic fluid as the liver, kidneys and spleen continue to develop.  A thin layer of lanugo (thin hair) is growing all over the body to provide warmth.

Your baby is now around the size of a naval orange, or about 10cm (4 inches), weighing in at 70 grammes (2.5oz). Your baby's legs are now longer than his or her arms. All four limbs now have functional joints, and although your baby is wiggling like crazy, you still probably can't feel the movements.

Your baby is now around the size of an avocado, or about 11.5cm (4.5 inches) and weighs in around 100 grammes (3.5oz). Your baby's eyebrows, eyelashes and hair are starting to come in, and taste buds are forming.  Your baby can start to detect sound around this time, too! Ultrasounds can start to determine gender from this stage.

Your baby is now around the size of an onion, or about 13cm (5 inches), and weighs in around 170 grammes (6oz). Your baby's bones are hardening, changing from rubbery cartilage to bone. Fat is accumulating around the bone and the umbilical cord is getting thicker and stronger.

Your sweetie is now around the size of a sweet potato, or about 14cm (5.5 inches), weighing in around 190 grammes (nearly 7oz). Your baby is amazingly active, passing the day (and night) kicking, punching, rolling around and generally being a little monkey!  You'll be able to feel all the movement very soon!

Your baby is now around the size of a mango, or about 15cm (6 inches), and weighs around 240 grammes (8.5oz). A greasy white coverage of lanugo, oil and dead skin cells covers your baby's whole body now. This week your little baby will start  an appetising diet of amniotic fluid which they are now capable of swallowing, digesting, and passing the fluid to their tiny 'large' intestines.

Your baby is now around the size of a cantaloupe melon, or about 16.5cm (6.5 inches) from head to bottom and weighs in around 300 grammes (10.5oz). Your baby's digestive system is now making meconium (a tarry black substance), which will fill the first nappy after birth. Your baby's genitals are now fully formed, too!

Your baby is now around the size of a banana, or about 26cm (10.5 inches) (now measured from head to toe) and weighs in around 360 grammes (13oz). Your baby gulps down amniotic fluid every day.  This gives hydration and nutrition and also practices swallowing and digesting. Taste buds are working too, meaning that your baby can probably taste what you're eating (especially strong tastes).

Your baby is now around the size of a papaya measuring between 26cm and 30cm  (10.5 to 12 inches) and weighing between 360 and 600 grammes (12 to 21oz). Your baby can now hear noise from outside the womb clearly, and will probably enjoy gentle music and find your own voice soothing. Sleep cycles are probably starting to kick in too, and your baby is sleeping around 12 to 14 hours per 24 hour period.

Your baby is now around the size of an aubergine, or about 34 to 38cm (13 to 15 inches) long and weighing in at between 680 grammes and 1kg (1.5 to 2.2lbs). Your baby's eyes are forming, and the heart is so strong that your partner will probably be able to hear the heartbeat by putting his ear to your tummy!  Baby is getting ready for the world outside and developing his or her immune system.

Your baby is now around the size of a squash at about 40cm (16 inches) long and weighing in at between 1.1  to 1.7kg (2.5 to 3.8lbs). All five senses are now functional, and your baby's energy levels are increasing.  You've probably felt a few punches or kicks by now, and sleep cycles are now settled in.

Your baby is now around the size of an honeydew melon at about 43-48cm and weighing between 1.9 and 2.6kg (4.2 to 5.8lbs). Your baby's senses are continuing to develop, and he or she can now sense light shining through your belly. Growth is now slowing, although your belly is already probably very stretched. The baby should start the journey down your pelvis during this period.

Holy cow! Your baby is now around the size of a watermelon at between 48 and 53cm (19 to 21 inches) long and weighing between 2.8 and 4.2kg (6.2 to 9.2lbs). You're now full-term, not long to go now!  If your baby is born now, it's considered a full-term birth, and the baby should be well capable or surviving outside the womb.  Time to get prepared!