What is the pregnancy month chart?

What does everyone go by as far as month by month of pregnancy? Do y’all go by 31 weeks as 8 months or 32 weeks? I’m confused

Okay for warning i am gonna rant ..... Yesterday was my baby boys 4 month check up and the are concerned of his weight but before he was gaining like crazy now all of a sudden him going from 9lb 11oz in june to 11lb 14oz yesterday isn't good. He was 6lb 5.9 oz when born. Also last month at my wic he weighed 10lb 6.5oz. I don't know if I am the only one but why do we have to have these growth charts every kid is different like right now my 4 month old is is the growth chart of 0-2y my other son is 5 and he getting called over weight at 51lbs and he in the growth chart of 2-20y. Why is our 2 years old and 5 years extra being compared to a 20 year old I know it's a growth chart but why compare kids to other kids they are all different and in all shapes and sizes cause my 4 month old is apparently too short too. Go figure.

I’m missing a lot of baby clothes so I’m going thru all his clothes and I’m finding different sizes in another drawer and I’m not understanding the Carter’s clothes chart. When it say 3 month is 0-3 or 3-6 and vice versa?

I'm 11dpo and tested negative- its my first month trying since having my daughter so I didn't expect getting pregnant the first month but I had this weird spotting- not really spotting- cm? Can you implant at 11dpo? I had no spotting and got my positive pregnancy test with my daughter 11dpo. Here is my bbt chart for reference for those of you who are great at reading bbt charts 😅😂

At how many weeks do you find out what you having this my second pregnancy but I don't remember what month.

One app saying 28 weeks is 7 month and this chart I have say 27 week is 7 month 😮‍💨🤦🏾‍♀️ which one is accurate

For any mom that has/had gestational diabetes and had to keep track, how did you make your chart or what did it look like.?

9DPO still just waiting…. This is my chart hopefully I’m pregnant. Took a test this morning. Definitely negative.. picture in comments

So im confused .. people are saying 18 weeks are 5 months when I turned 20 weeks I thought that made 5 months my doctors told me every 4 weeks is a month added … im so confused I tried going by the chart on google but my mom said it’s wrong ?

Has anybody else done the Chinese gender chart thing? If so how accurate was it?😅 #pregnant