The development standards of babies over 8 months old include height and weight standards, vision standards, hearing standards, language standards and action standards. Moreover, there are some physiological differences between male and female babies, which need to be checked according to gender.

1. Height and weight standard: for boys over 8 months, the height standard is 66.0-76.0cm and the weight is 7.0- 10.7kg, and for girls, the height standard is 64.0-74.2cm and the weight is 6.4-10.0kg..

2, vision standard: the baby's vision over 8 months is equivalent to 900 degrees, which is often said to be 0.1;

3. Listening standard: Babies over 8 months old can pay attention to hearing small external environmental sounds, such as rain and wind. Can distinguish the attitudes, faces and voices of adults and make different reactions at the same time;

4, language standards: babies over 8 months can imitate adults to make repeated continuous pronunciation, and many babies begin to unconsciously call their mothers or imitate their own simple pronunciation;

5. Action standard: Babies over 8 months old are no longer satisfied with crawling and sitting, but begin to learn to stand and crawl, and can clap their hands or wave their hands to express different meanings;

6. Other development criteria: At this stage, the baby's head circumference is 4 1.5-46.7cm, and 2-4 teeth should erupt, and the size of the halogen door is about 1.5cm wide.

When the baby of more than 8 months has abnormal height and weight or other abnormal behaviors, parents are advised to take him to the hospital in time to find out the specific reasons.