By Sally Robertson, BSc
During the 25th to 28th week of pregnancy, the baby is very active, moving about vigorously and responding to sounds and touch. Loud noises may make the baby kick, which the mother should be able to feel.
Medical accurate 3d illustration of a fetus week 25. Image Copyright: Sebastian Kaulitzki
During this period, the baby’s eyelids will also open and the baby will start to blink. Major organs such as the lungs and brain are formed, but not yet fully developed and these will continue to develop throughout the rest of the pregnancy.
The mother may find the baby starts to take up so much space in her abdomen that eating large meals is difficult and indigestion is a common problem.
The mother may also experience water retention and swelling in the feet, hands or face.
This is normal, but mothers should mention this to their General Practitioner (GP) so that they can rule out the possibility of a condition called pre-eclampsia that causes swelling during pregnancy.
In the 25th week of pregnancy, the baby’s reflexes are developing and the baby may move in response to familiar sounds such as the parents’ voices. Most of the vital organs are formed and the skin is becoming less translucent.
From this point, the remainder of the pregnancy is mainly about growth, so mums-to-be need ensure they eat and rest well.
At 26 weeks, the baby’s lungs start to produce surfactant, which allows the lungs to inflate without the air sacs sticking together on deflation. By this stage, the baby is around 230mm in length and weighs about 800 grams.
A major growth spurt is also about to occur and eating well is important for healthy development of the baby’s brain and senses.
Week 27 marks the end of the second trimester. The baby now measures around 340mm and weighs about 820 grams (almost 2 pounds).
The lungs are now developed, although they are immature. In order to prepare for life in the outside world, the baby breathes in amniotic fluid, which can cause it to hiccup. The jerk of each hiccup can then be felt by the mother in her tummy.
At this stage, the mother may be checked for anemia, which can cause fatigue and affect the health of the placenta. If a mother is anemic, it is very important that she increases her iron level by boosting it with iron supplements
Week 28 - The third trimester
The baby continues to develop during the third trimester. He/she will open their eyes for the first time and the eyelids are partially developed and the eyelashes present.
The baby continues to gain weight and wrinkles on the body start to smooth out as fat is stored. The skin also starts to become flesh colored.
Pregnant woman with visible uterus and fetus week 28. Image Copyright: Sebastian Kaulitzki / Shutterstock
The baby now measures around 250mm and weighs around 1,000 grams or 2 and 1/4 pounds. Babies born at this stage have a very good chance of survival, without there being any risk of physical or mental disability.
It is now possible to listen to the baby’s heartbeat using a stethoscope. The baby’s heartbeat may be heard if you put an ear to the mother’s abdomen.
Reviewed by Yolanda Smith, BPharm
Last Updated: Jun 27, 2016