Is the 6th month starting at 21 weeks???

[pacifica]

I just got a copy of The Pregnancy Book today by William Sears and was surprised to see the 6th month of pregnancy starting at week 21! Is this correct? I haven't looked at another pregnancy book to compare, but I was thinking weeks 20 to 24 were the 5th month.

[Funny Face]

Not sure it matters either way but...

20 weeks = 5 months so I could see calling week 21 as part of the '6th month' if you so desired.

[MacKinnon]

Who knows! People ask how many months I am and I go, "ummm... I don't know, I'm 20 weeks, so I guess that's what, 5 months?" I can only track weeks!

[tinynyota]

Well, I guess I'd agree that 21 weeks means you've finished 5 months and are now "in your 6th month". But you aren't "6 months pregnant" until you've completed that 6th month which would be after 24 weeks.

I'm constantly confused by how different books/sites/docs date things so I always have to think it through like that!

[BreakfastyMichele]

Tinynyota is right, you're in your sixth month, but not yet six months pregnant. [an easy way to wrap your brain around it: Your baby will be in his first year of life the moment he's born, but he doesn't become ONE until he's finished that year.]

Different books and sites date things differently, so just choose what works for you. Be mindful, though, that only one month has exactly four weeks, and most have nearly half a week more. . .so there's leeway.

Personally, to calculate how pregnant I am by month, I count backward from my due date. I'm due 3 July, so I will be seven months pregnant on 3 May.

[CherryBomb]

This is why I just go by weeks. I'm 15w5d. So much easier

[PugMom4Now]

I go by weeks as well as everyone calculates different. When I want to say months, I give a month by counting back from my EDD. I'm almost into single digit weeks left, so I plan to start saying how many weeks I have remaining.

One note on the Dr. Sears pregnancy book, they calculate weeks from ovulation date, not from LMP, so being 21 weeks according to the book is most likely 23 weeks according to most other calculations.

[porcelina]

Go to the beginning of the descriptions, and you'll see that the Sears book counts from conception, not from last LMP. So their 21 is really 23.

Though, technically, STARTING the 6th month would mean the completion of 5 months, which is 5*30 days = 150 days, which, divided by 7 is 21.4 weeks.

Hmm, well, whatever!!

[micah_mae_]

http://myparentingguide.com/img/preg..._trimester.PNG

I like that chart.

[matthia]

every single stupid book and website and dr seems to want to shove 40 weeks into 9 months, and I'm telling you, it just DOESN'T. (can you tell this is a pet peeve of mine?).

40 weeks = 10 months. Therefore, while Dr. sears would like me to believe that 6 months lasts for 5 weeks and 9 months lasts for 6, I am stubbornly sticking to what I know. I am 29 weeks today? ok, then I am 7 months and a week pregnant.

(and don't even get me started on the the 2 weeks that they count when you aren't pregnant yet, which really means you're pregnant for 38 weeks (or 9.5 months) which means I'm really only 6 months + three weeks pregnant....I'm using 40, and in my world 4 weeks is a month.)

[aikigypsy]

Yeah, but you're not pregnant for 40 weeks unless you go 2 weeks "over" at the end. Pregnancy is about 9 lunar months from conception to EDD. I believe in subtracting 2 from the official number of weeks and dividing by 4 or so. So now I'm "18 weeks" which is really 16 weeks from ovulation/conception, I'd figure that's about 4 months. 40 weeks-2 =38/4=9.5... so not perfect, but close enough.

[BreakfastyMichele]

Matthia, that is hilarious that your pet peeve is folks who cram 40 weeks into nine months. Mine's just the opposite: if 40 weeks is ten months, and there are 52 weeks in a year, wouldn't twelve weeks mean there are three months left in a year? Or. . .my last period started the first week of October, and I'm due the first week of July--that looks like nine months to me (even if you include the two freebie weeks aikigypysy cites.)

I guess some books think like you do, and some like me!

[jenifera2]

I think someone pointed out earlier that only one month is actually only 4 weeks. People who say pregnancy is 9 months are going by calendar months, not lunar months (which are actually 29 days, not 4 weeks).

The problem with counting months is that a month is not a fixed period of time. One day is 24 hours, fixed. One week is 7 days, fixed. One month varies from 28 to 31 days and depends on your definition of the word "month".

If you're looking at 9 calendar months, those 9 months will last anywhere from 273 to 276 days, with an average of 273.75 days (not counting leap years). That means those 9 months will last anywhere from 39 weeks to 39 weeks and 3 days, which is pretty close to either 40 weeks (standard counting) or 38 weeks (gestational counting).

Bottom line, at least to me, is that months are a meaningless number to talk specifics with, since we all use them differently and they're of varying lengths. So, why sweat the exact number of months when we have better counting methods for when it really matters. No casual acquaintance who asks how far along you are will see any difference between 5 and 6 months anyway.

[MammaB21]

This all just depends on how you're counting. If you're talking lunar months, than 40 weeks would equal 10 months when each 'month' is 4 weeks long. In that case you would be starting your 6th month at 20 weeks, finished at 24 weeks. This is the simplest way to break it down and probably the most common.

If you are counting by calender months things get a little more confusing (well, to me anyways). I guess if you assume the average month is 30 days long, than things pan out. 40 weeks of pregnancy would be 280 days which is about 31 days in 9 months. So that would be pretty consistent to average calender months in length. The trouble is that you can't assign a nice day to use as a milestone each month because each month is different.

That's not even to address the fact that the first two weeks of pregnancy you aren't even pregnant. So we're actually only pregnant for 38 weeks which would be 9.5 lunar months, and less than 9 months in calender months since it would bring the average calender month days down to 29. It's confusing and I wish we could come up with a system that everyone agreed on and was actually accurate.

[matthia]

Originally Posted by BreakfastyMichele

Matthia, that is hilarious that your pet peeve is folks who cram 40 weeks into nine months. Mine's just the opposite: if 40 weeks is ten months, and there are 52 weeks in a year, wouldn't twelve weeks mean there are three months left in a year? Or. . .my last period started the first week of October, and I'm due the first week of July--that looks like nine months to me (even if you include the two freebie weeks aikigypysy cites.)

I guess some books think like you do, and some like me!

Haha, oh don't worry, I know it's a rediculous thing to have a pet peeve about, and it doesn't help that I logically know that 30/31 days ISN'T a perfect 4 weeks either. However, in an effort to NOT go insane I decided at about 12 weeks or so to stop agonizing over "ok, MW says I'm 12 weeks but I know I conceived 10 days after my LMP, which means baby is actually a week and a half younger, which means s/he's about here in developement and on, and on, and on , and on, and on....." And I decided 40 weeks= 10 months=4weeks/month=I'm 7months +1 week today!

saves me a headache....as long as no one questions my math!!

[MammaB21]

Originally Posted by matthia

However, in an effort to NOT go insane I decided at about 12 weeks or so to stop agonizing over "ok, MW says I'm 12 weeks but I know I conceived 10 days after my LMP, which means baby is actually a week and a half younger, which means s/he's about here in developement and on, and on, and on , and on, and on....."

Actually if you're counting in weeks most all web sites/books/OBs/MW etc are counting your date from your LMP. Even if you calculated your due date using your ovulation date, they will still tack on an extra two weeks. In my case, I O later, so my EDD was calculated based on that. There is still an extra two weeks added onto it which would have put my LMP a week later than it actually was. Anyways, regardless of EDD's and LMP's anything that is telling you the development of baby (mostly) is using the extra two week rule. So taking that two weeks off when looking at developmental milestones is only going to give you false information. Unless it specifically says: 10 week old fetus ..... it really means 10 weeks pregnant/8week old fetus. Ugh, now I have a headache...

[Naomismom]

For some reason this drives me bananas. I don't like to hear someone complain about being 8 months pregnant when they're 32 weeks. You're only 7, you don't deserve the bragging right of being 8 . Since when is the remaining 8 weeks equal to a month?

Perhaps we should start a trend of specifying whether or not we are using a calendar-month system or a lunar-month system.