Pregnancy week by week
Pick your week for what the baby is doing, how you might feel and what is booked that week in the Australian public system. If you do not know your week, enter your due date and we take you there.
First trimester · weeks 4 to 13
4A poppy seed1 mmThe embryo has implanted and the placenta and amniotic sac are forming.5A sesame seed2 mmThe neural tube (brain and spinal cord) is forming; the heart begins to beat around the end of this week.6A lentil5 mmThe heartbeat can be seen on ultrasound; tiny arm and leg buds appear.7A blueberry1 cmThe brain is growing quickly; the face, nostrils and eye lenses are forming.8A raspberry1.6 cm · 1 gFingers and toes are forming and the embryo moves, although you cannot feel it yet.9A grape2.3 cm · 2 gAll the major organs have started; the tail is gone.10A strawberry3.1 cm · 4 gOfficially a fetus now; nails and hair follicles are developing.11A fig4.1 cm · 7 gBones are hardening and the baby can open and close its fists.12A lime5.4 cm · 14 gReflexes are developing and the kidneys make urine.13A pea pod7.4 cm · 23 gVocal cords and fingerprints are forming.
Second trimester · weeks 14 to 27
14A lemon8.7 cm · 43 gThe baby can squint, frown and may suck a thumb.15An orange10 cm · 70 gThe skeleton is forming and the legs are now longer than the arms.16An avocado12 cm · 100 gThe eyes move and the ears are in position; the baby hears muffled sounds.17A pear13 cm · 140 gFat starts to form under the skin; the umbilical cord thickens.18A capsicum14 cm · 190 gThe ears stand out and the baby may hear your voice.19A mango15 cm · 240 gVernix, a protective coating, forms on the skin.20A large banana25 cm · 300 gHalfway. The baby swallows amniotic fluid and meconium forms in the gut.21A carrot27 cm · 360 gMovements become stronger and more regular.22A papaya28 cm · 430 gEyebrows and eyelids are distinct and the grip is stronger.23A corn cob with its husk29 cm · 500 gThe lungs start producing surfactant; hearing is well developed.24A 30 cm school ruler30 cm · 600 gA viability milestone; the skin is still thin and translucent.25A continental cucumber35 cm · 660 gThe startle reflex appears and the hair has colour.26A head of cos lettuce36 cm · 760 gThe eyes open and the baby responds to sound and light.27A bunch of celery37 cm · 875 gRegular sleep–wake cycles; the brain is very active.
Third trimester · weeks 28 to 42
28A butternut pumpkin38 cm · 1.00 kgThe baby can blink and dream (REM sleep).29A bunch of rhubarb39 cm · 1.15 kgMuscles and lungs are maturing; the head grows to fit the brain.30A pineapple with its crown40 cm · 1.32 kgThe baby regulates its own temperature better; bone marrow makes red cells.31An A3 sheet, long side41 cm · 1.50 kgRapid weight gain; all five senses are working.32A leek42 cm · 1.70 kgOften head-down by now; practising breathing movements.33A full-size computer keyboard44 cm · 1.92 kgThe skull bones stay soft to pass through the birth canal.34A rolling pin45 cm · 2.1 kgFingernails reach the fingertips; the nervous system is maturing.35A small watermelon46 cm · 2.4 kgThe kidneys are fully developed and the liver processes waste.36A standard pillow, short side47 cm · 2.6 kgThe baby drops lower into the pelvis, especially in a first pregnancy.37An oblong watermelon49 cm · 2.9 kgEarly term. The lungs are ready for air in most babies.38A large leek50 cm · 3.1 kgShedding lanugo and vernix; a firm grasp.39A short baguette51 cm · 3.3 kgFull term. Brain and lungs keep maturing right up to the birth.40A ukulele51 cm · 3.5 kgDue date. The average birth weight in Australia is about 3.3–3.4 kg.41A baguette52 cm · 3.6 kgLate term; the placenta is checked more closely.42A carry-on suitcase52 cm · 3.7 kgPost-term.