Your baby is conceived
January 22, 2026
Baby's Size This Week
Week 12
Lime
Your baby is about the size of a lime this week
2.13 inches
5.4 cm
Length
0.49 ounce
14 grams
Weight
Baby Status
Heart Rate
110-180 bpm
Hiccup Episodes
~2per day
Listen to Your Baby's Heartbeat
Week 12 - Your baby's heart beats with life
145
BPM
Your baby's heart has beaten 9,825,019 times since conception
Pregnancy Achievements
Heartbeat Hero
Week 6 - Heart starts beating
Tiny Human
Week 10 - All organs formed
1st Trimester Champion
Week 13 - First trimester complete
Halfway There!
Week 20 - 50% complete
Viability Victory
Week 24 - Baby could survive outside womb
Dream Weaver
Week 28 - REM sleep & dreaming begins
Significant Milestones in Embryo/Fetal Development
✨
Week 2
🧪
Positive pregnancy test
February 05, 2026
Week 4
❤️
Organs begin to form, heart starts beating
February 12, 2026
Week 5
🩺
Major organs have formed, heart can be heard
March 19, 2026
Week 10
🛡️
Second trimester, risk of miscarriage decreases
April 02, 2026 - You are here
Week 12
📢
Now is a good time to announce your pregnancy
April 16, 2026
Week 14
👁️
Your baby can now see light
April 23, 2026
Week 15
🔍
Your baby's gender is visible on ultrasound
April 30, 2026
Week 16
🤰
You can feel your baby move around
May 14, 2026
Week 18
👂
Your baby can now hear sounds
May 21, 2026
Week 19
🏥
Premature babies have a chance to survive
June 18, 2026
Week 23
🌬️
Third trimester, your baby can breathe
July 16, 2026
Week 27
💅
Fingernails and toenails have formed
August 20, 2026
Week 32
✅
Your baby is now considered full term
September 24, 2026
Week 37
🎉
Your baby is due any time now!
October 15, 2026
Week 40
Weekly Development Progress
Your baby is now around 5.5 centimetres long (about 2 to 2.5 inches). He or she weighs in at around half an ounce and is getting bigger and heavier by the day. The brain and central nervous system are becoming more complex now, and are allowing your baby to make more deliberate movements inside your womb.
Your baby's reflexes are improving around now, and he or she can move it's tiny fingers and toes. Your baby may be sucking its thumb and can even respond to your touch, although you're unlikely to feel any movement yet, especially if this is your first pregnancy. It may seem strange that this little lime-sized person can do so much already, but babies are much more clever than we often give them credit for!
Video & Ultrasound Pictures
Video
Development Week 12 Video
Ultrasound Week 12 Picture
Ultrasound Week 12 Picture
Baby's Weight Journey
Your baby weighs approximately
0.5 oz
(14g)
+0.2 oz this week - about the weight of a cherry!
Baby's growth curve (weeks 8–42)
What Your Baby Can Hear
Your baby's ears are still developing. At week 12, the inner ear structures are forming. Baby will begin hearing around week 18.
Hearing Development Timeline
Week 6
Inner ear begins forming
The cochlea and vestibular system start developing from the otic placode.
Week 16
Ears reach final shape
The outer ears are now fully formed and in their correct position on the head.
Week 18
First sounds detected
Baby begins to hear internal sounds: your heartbeat, blood flow, and digestive system.
Week 22
Responds to voices
Baby can hear your voice and may respond to it with movement. They prefer low-pitched sounds.
Week 25
Reacts to music
Baby can hear music and external sounds. Studies show babies prefer classical and soft music.
Week 27
Startles at loud noise
The auditory system is mature enough to startle at sudden loud sounds.
Week 32
Recognizes your voice
Baby can distinguish your voice from others and shows a preference for it after birth.
Week 35
Remembers music
Research shows babies can remember and recognize melodies heard in the womb after birth.
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