Beware of gaining too much/not gaining enough weight!
Gaining too much weight during a pregnancy will make you susceptible to pregnancy induced hypertension. However, recent trends have been seeing mothers-to-be that are too slim. It is said that not gaining enough weight will result in not only a smaller infant but also makes you susceptible to lifestyle related diseases. In any case, weight control during gestation is very important.
How much weight gain is normal during pregnancy?
The weight a pregnant woman gains until birth mostly consists of the weight of the infant (fetus), placenta, amniotic fluid and blood. A newborn's average weight is approximately 3 kilograms. It is said that a mother-to-be's body stores up necessary nutrients for birth and breastfeeding during pregnancy as well. In recent time, weight gain calculated according to each individual's pre-pregnancy weight seems to be the most ideal.

Physical Growth & Development Guidelines:
4 - 6 months
These data of boys and girls height/weight are different from
Singapore rule. This is based on the Guidelines and Instruction for Maternal and Child Health in Japan.
Infants 4 - 5 months:
Infants start to have more interest in their surroundings
Almost all babies master head control by this time.
Their field of vision widens and they start to put anything they can get their hands on into their mouths.
Holding babies in a standing-up position on your lap will cause them to push down with their feet.
They distinguish day from night, and will stay awake longer during the day and sleep at night.
Important Tip for Mummies:
Adjust your daily schedule to create a contrast between day and night by actions such as taking walks during the day.

For Boys
For Girls
Height: 60.0 - 69.9 cm
Weight: 5.6 - 9.2 kg
Height: 58.0 - 68.2 cm
Weight: 5.1 - 8.7 kg
Infants 5 - 6 months:
Some babies may start to sit up
Slowly introduce solids during this period.
Infants will be able to sit on their own with a bit of support on people's laps or on a baby chair.
They will be able to stretch out and grasp things they are interested in.
They will touch anything and put everything into their mouths.
Some babies will start rolling over by themselves. They also start to express likes and dislikes.
Important Tip for Mummies:
Infants during this period will touch and put anything in their mouths, Be aware of your baby's environment and avoid putting objects that may pose a hazard around your baby.

For Boys
For Girls
Height: 61.9 - 71.6 cm
Weight: 6.1 - 9.7 kg
Height: 59.9 - 70.0 cm
Weight: 5.5 - 9.2 kg