All Pregnancy Weeks
Second TrimesterWeek 15 of 40

Pregnancy Week 15: The Light Sensor

Updated

Your baby this week
About the size of an apple
~4.0 in · ~2.5

Medical Disclaimer: Content is for informational purposes only and does not replace professional medical advice. Always consult your healthcare provider.

How your baby is growing this week

Apple size — 4 inches. Eyes can sense light through closed lids. Legs are now longer than arms. Skeleton transitioning from cartilage to bone. Taste buds forming — baby tastes the amniotic fluid.

What your partner is going through

Pregnancy brain is real and scientifically documented — grey matter volume temporarily decreases as the brain rewires for parenting. Forgetfulness, lost keys, trailing off mid-sentence. Not laziness, it is neuroplasticity.

What to focus on this week, dad

  • 01Dental Audit: schedule a cleaning for her — pregnancy gingivitis affects 60-75% of pregnant women. Hormones increase gum inflammation and bleeding. Schedule yours too while you are at it
  • 02Become the household memory. Set reminders for her appointments, take notes at OB visits, track medication schedules. Her brain is literally reorganizing
+1 more focus item in the full briefing for week 15 — Start free

Connect with your partner

Write things down for both of you. Shared calendar, shared notes app, a whiteboard on the fridge. Do not mock the forgetfulness — she is frustrated enough already.

Source: ACOG

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