Why is the 28th week of pregnancy crucial?

At week 28, you are in the early phase of the third trimester. At this stage, the baby is already past its biological growth. The eyelids are open, fat starts to deposit, bone marrow starts producing red blood cells, the baby can breathe, and REM sleep patterns result in dream-like activity.

What are the signs of a healthy 28-week baby?

A healthy week 28 baby can experience REM sleep patterns, blink their eyes, make faces and begin to form a round appearance.

Week 28 of Pregnancy: Baby Growth, Brain Development, and Dreams in the Womb

At 28 weeks of pregnancy, your baby is practising life skills like blinking and switching between REM and non-REM sleep. During the third trimester, the foetus spends 90% of its time in a sleep state. But how do foetuses dream inside the womb? During REM sleep, the baby's eyes flicker and twitch along with intense, chaotic brain activity that resembles dream-like activity. Ultrasound results reveal babies rest in the womb and also actively process and rehearse for life after birth.

Foetuses’ dreams are not like adults’ and children’s dreams. Instead, they are neural rehearsals and experiential memories drawn from the flashes, sounds, and movement to nurture the network. Your foetus is just re-experiencing your heartbeat, rocking motion, and your voice in the womb. As the third trimester rolls, the dream-like patterns will be more prominent.

Neurological and Brain Development in Week 28

From primitive neural activity to organised brain function, your baby’s neurological development sees a transformative growth from week 20 to week 28. Most of the baby’s brain structure is already developed. This week, the foetal brain transitions into mimicking postnatal patterns of activity.

Before the third trimester, the brain resembles a smooth surface, which now folds into gyri and sulci. This cortical fold increases surface area, providing more space for cognitive processing.

At week 28, the brain weighs about 350 to 400 grams and will triple in size before birth. The cerebral cortex, which is responsible for thought processing and sensory recognition, grows rapidly. Myelination, the process of covering neurons with a fatty sheath, helps the foetal brain communicate efficiently.

Sleep Architecture in the Foetus

Foetuses don’t sleep like adults. It follows a structure in which the foetus cycles between intense, active Rapid Eye Movement (REM) and quiet Non-Rapid Eye Movement states. For adults, REM helps process emotions, crystallise memories, and strengthen learning. For the foetus, REM helps in organising the brain’s sensory and emotional circuits.

External stimuli such as music, rocking motion and light can trigger foetal movement. But during REM sleep, the sensory cortices light up and act as an internal stimuli. The frequent REM state strengthens the baby’s auditory system, enabling it to easily recognise low-frequency sounds, such as the mother's heartbeat.

During the silent non-REM state, the fleeting experiences and sensations are recorded. During the REM shift, the foetus re-experiences the same sensation while replaying and reorganising the memories. The process of transforming short-term neural activity into long-term storage is known as memory consolidation.

Foetal Milestone in Week 28

This week, your baby is settling into its birthing position, head down and feet up. The foetus is about 1 to 1.2 kilograms and measures roughly 37 - 38 centimetres. The baby’s brain is developing rapidly and continues to grow at a rapid pace. A few milestones include:

Babies spend 80 to 90% of their time sleeping, and most of that time is spent in the REM state.
The foetus’s retina can now detect the light filtered through the uterus and shadow changes.
The limbic system, which is the foundation of emotional awareness, connects with the brain centres.
Baby’s bone marrow produces red blood cells for independent oxygen transport
Active dreaming activity is evident with rapid eye bursts, breathing fluctuations and muscle twitches.

Pregnancy Symptoms at Week 28

As the third trimester progresses, expectant mothers experience visible physical, emotional and hormonal changes. These changes indicate that your baby is growing rapidly in the womb and your body is adapting to accommodate the growing baby. Here are a few pregnancy symptoms you might notice in pregnancy week 28.

Baby’s REM sleep state may bring vivid and intense dreams.
An expanding uterus may cause breathlessness while climbing stairs and lying down.
Frequent Braxton Hicks contractions or fake labour may last for 30 to 60 seconds.
The immediate weight surge may put extra strain on the lower back, pelvis and joints.
Hormonal fluctuations result in frequent urination.
Increased blood volume and fluid retention may cause mild swelling.

Practical Care for Healthy Foetal Brain Development

For better baby's brain and biological development, you can follow the below practical guidance.

Follow a consistent bedtime routine and prioritise restful sleep.
Sleep in a comfortable position and support your belly with a pillow.
Practice mindfulness to reduce cortisol levels and stabilise the baby’s circadian rhythm.
Avoid a chaotic environment and surround yourself with gentle sounds and relaxing music.
Optimal hydration and adequate nutrition with all the prenatal nutrients and vitamins for better baby growth.
Keep your emotional well-being in check to help modulate the foetal limbic response.

You are getting closer to labour, so hang in there and keep focusing on nurturing your health. Your baby’s REM sleep pattern directly affects you. Your baby’s growth impacts your physical and hormonal changes. All this suggests that you are not a lone player. You and your baby are in this together. After birth, this harmony breaks.

At this final stretch and week 28, the baby is not just receiving biological development. The baby is also actively shaping its neural activity, consciousness, emotional intelligence, and memory for the world outside.

Whether you’re pregnant, a new mom, or navigating postpartum, you don’t have to do it alone. Join our support group to connect, share, and support one another.

FAQs on Week 28 of Pregnancy: The Moment Your Baby Starts to Dream

Why is the 28th week of pregnancy crucial?
At week 28, you are in the early phase of the third trimester. At this stage, the baby is already past its biological growth. The eyelids are open, fat starts to deposit, bone marrow starts producing red blood cells, the baby can breathe, and REM sleep patterns result in dream-like activity.
What are the signs of a healthy 28-week baby?
A healthy week 28 baby can experience REM sleep patterns, blink their eyes, make faces and begin to form a round appearance.