At 25 weeks, you are more than halfway through the sixth month of your pregnancy. It is a great time to bond with your unborn child, so grab a children’s book and start reading to him every night. By the 25th week, the fetal hearing is often matured enough for him to respond to your voice with a tiny punch or kick .
Baby development during the 25th week
The brain continues to grow with its cortex developing distinct layers; however, most of the fetal actions are still monitored by other, earlier developed brain areas .
Sensory organ development
The senses of hearing, vision, touch and taste are still maturing with your baby responding to loud sounds and tasting the amniotic fluid as he swallows it. The optic nerves are developing as your baby is now likely to respond to a flashing light by turning his head to a side .
Internal organ development
One major change this week is the opening of the baby’s nostrils that were previously plugged up . The lungs are preparing for breathing air as your baby inhales and exhales amniotic fluid, while surfactant, the chemical substance that helps the lungs to expand with oxygen, also develops. However, if you were to give birth this week, the baby would need medical assistance to carry on breathing as the lungs are still too immature to distribute oxygen to the bloodstream or releasing carbon dioxide .
The intestinal tracts are maturing as well with meconium, the first bowel movement of your baby after he is born, forming in his large intestines .
His wrinkled skin is starting to smoothen out as fat grows underneath it, giving him a chubbier appearance . The tiny blood vessels known as capillaries are developing just beneath the skin, giving your baby a pinkish hue .
Fetal movement and heartbeat
Most pregnant women report their babies to be most active during the period between weeks 24 and 28. So, you are probably feeling your little one’s kicks, flips and punches all day long. It is a good sign when the baby moves a lot, as it only indicates proper fetal health and not that you are going to have a hyperactive baby . You may also feel baby hiccups, a rhythmic movement that lasts for a few minutes at a time.
The fetal heartbeat ranges anywhere between 120 and 160 beats/minute with your doctor now being able to hear it using a Pinnard’s stethoscope .
How big is your baby this week?
Your baby is about the size of a small acorn squash  with his crown-to-ankle size ranging from 13 to 13.5 inches (33.02 cm to 34.29 cm), while weighing around 1.5 pounds (680.39 gm) .
Belly and body changes during pregnancy week 25
The uterus is about the size of a soccer ball by this week , measuring around 25 cm in diameter from your pubic bone up to a point halfway between the bellybutton and sternum . It is now pushing other organs like the lungs and intestines to make space for itself, which leads to certain pain and discomfort.
Fluid retention and increased blood volume due to pregnancy often puts pressure on a major nerve in your hand, leading to a tingly and numb fingers and palms (carpal tunnel syndrome) . You may also notice a yellowish fluid (colostrum) leaking from the nipples as your body prepares for breastfeeding. Other, more positive body changes include your flowing lustrous locks and those fast growing nails, resulting from the circulating pregnancy hormones .
Recommended caloric intake and weight gain
The recommended weight gain in the second and third trimesters is about a pound every week. Following a proper diet is important for healthy weight gain as you do not require any more than 300-340 additional calories in a day when carrying a single baby . The recommended calorie level goes up to about 600 per day during the 25th week in a twin pregnancy .
25 weeks pregnant tests and ultrasound
From this week forward, your doctor is likely to check your blood pressure in every prenatal visit to detect any risk of preeclampsia . You may also be asked to take the glucose screening test (if you have not already) to check for gestational diabetes . Those with a high risk of the condition are sometimes asked for a urine sample to be tested for any trace of glucose .
Your caregiver may also recommend an ultrasound scan to evaluate the development of the fetal brain and internal organs.
A 3D ultrasound performed this week shows your baby to look like a tiny version of what he will look like on his birth . You may catch him yawning, sucking his thumb or even rubbing those little eyes .
Pregnancy week 25 signs and symptoms
- Round ligament pain
- Joint, hip and back pain
- Pelvic girdle pain or symphysis pubis dysfunction 
- Tailbone pain
- Swelling of the hands and feet
- Shortness of breath 
- Leg cramps
- Hot flashes (because of the pregnancy hormones) 
- Indigestion and heartburn
- Gas, bloating and constipation
- Abdominal tightness and Braxton Hicks contraction 
- Dry, itchy eyes that may be sensitive to light 
- Sensitive skin 
- Stretch marks
- Itchy skin rash, especially around the growing belly, back and thighs
- Dark patches in various skin areas, especially the face (mask of pregnancy)
- Soreness and occasional sharp pain around your bellybutton
- Varicose veins and hemorrhoids 
- Rapid emotional changes and depression
- Sleep disturbances and restless leg syndrome 
- Frequent urination
When to call the doctor?
- Vaginal bleeding with abdominal cramps, lower back pain, feeling pressure in the pelvic area, uterine contractions, diarrhea and leaking a thin clear fluid (all these symptoms together might indicate preterm labor) 
- Severe itching without any rash, especially of the palms and feet (might indicate obstetric cholestasis) 
- Sudden swelling of the face, hands and feet along with persistent headaches, lightheadedness, extreme fatigue and vision changes (might indicate high BP or preeclampsia) 
- Noticing a decrease in fetal movement
- Pain or burning sensation while urinating, yellowish or greenish jelly like or thick white discharge with strong odor and lower back pain (might indicate a kidney or yeast infection) 
- Feeling exhausted all the time along with excessive thirst, severe nausea and sudden changes in vision (might indicate gestational diabetes) 
- Mild spotting, pelvic pressure along with throbbing back and stomach pain and a change in vaginal discharge (might indicate an open cervix) 
- Severe nausea, vomiting and/diarrhea lasting for over 24 hours
Tips for a healthy pregnancy and baby
- Maintaining proper dental health as pregnancy increases the chances of gingivitis (inflamed, bleeding gums) that might lead to a serious infectious condition named periodontitis which is often associated to an increased risk of preeclampsia and early labor and delivery 
- Doing prenatal yoga or some light exercise everyday (unless your doctor advices otherwise); make sure to stop working out if you feel any pain or are extremely tired, dizzy or out of breath 
- Practicing lying on your left side as lying on your back can reduce blood flow to the placenta 
- Drinking lots of fluids as it helps to fight constipation, fatigue and dizziness by preventing dehydration
- Consulting your doctor regarding any necessary vaccination or a Rhogam shot (for Rh negative women) 
- Talking to your doctor regarding the safety of flying if you are planning to travel in the coming weeks [safety of flying during pregnancy]
- Following a diet containing lots of fiber rich foods (whole grains, fresh fruits and vegetable) in your daily diet to avoid constipation
- Eating plenty of calcium rich foods, like low fat yoghurt, cheese and cottage cheese, to get the daily recommended value of 1,000 mg calcium 
- Doing pelvic floor or Kegel exercises for strengthening you pelvic muscles 
- Consulting your health care provider before taking medications like Xanax and Zoloft
- http://www.babycenter.com/slideshow-baby-size?slideNumber=23 [/ref]