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weeks vs months

(18 Posts)
Dawn2820 Wed 20-Jun-07 17:08:07

if i am 20 +4 weeks how many months am i?

what are you?

Pixiefish Wed 20-Jun-07 17:14:00

I'm about 20 weeks so I say about 4 1/2 months. Complicated by the fact that arpegnancy is actually 40 weeks so if you average 4 weeks in a month (which I know you can't as there are 5 week months) a pregnancy is actually 10 months.Or I just say half way

RGPargy Wed 20-Jun-07 17:16:58

I am 17+2. Next week when I'm 18 weeks, i will say i am 4 1/2 months because i base it on 4 weeks to the month.

aikigypsy Wed 20-Jun-07 17:29:13

I think that the whole "pregnancy is 40 weeks, which is 10 months," thing is confusing, because of those 2 extra non-pregnant weeks they throw in to make it a round number. Really, it's 38 weeks (on average) counting from conception, which works out to a little less than 9 months. So here I am at almost 20 weeks, and I figure that in another week (at 21 weeks, or 19 real weeks) I'll be at halfway, 4 1/2 months.

dal21 Wed 20-Jun-07 17:44:50

I am 25+5 - so am just over 6 1/2 months. At week 27 am into month 7 and final trimester.

At 20 weeks, you pass the half way mark so you are 4 1/2 months pregnant! Have a celebration! you are over halfway through!

designerbaby Wed 20-Jun-07 17:49:33

Ah but there's more than 4 weeks to a month... 4 weeks is 28 days - months are either 30 or 31, not counting Feb (which just messes things up annoyingly).

If you do 30.5 (to split the difference and take in Feb's nasty 28 days) x 9 you get the number of days (around 274.5) then divide by 7 to get the number of weeks its 39.214... (or 40 for non-aspergers people unlike myself ). Which clears up the whole month/week conundrum tidily.

If you want to know what you are in months do your number of weeks multiplied by 7, add any extra days you're counting, divide by 30.5 and you'll get a rough idea of the number of months.

eg. I'm 21 weeks = 147 days
plus 4 days = 151 days
divided by 30.5 = 4.951 months

Which for the sake of not freaking people out, I'll describe as 5 months....

But this is always counting from the date of your last period. Conception is actually about 2 weeks later, so you do get 2 weeks "free" if you like (as an introductory offer). BUt since this is taken into account in both week and month calculation it doesn't make a difference in this case.

Using this formula I can categorically state, Dawn, that you are 4.721 months pregnant.

Mathematically speaking that should round down to 4 and a half months, but I'm sure you wouldn't get into too much trouble if you were feeling optimistic and said 5 - which you can legitimately (and mathematically) do tomorrow anyway.

There. Bet you wish you hadn't asked... And this makes me officially tragic.


MrsMar Wed 20-Jun-07 18:46:32

I'm 27 weeks today, there are 52 weeks in a year so I said I was officially 6 months pg last week. However, it was three calendar months yesterday to my due date (19/9), I usually tell everyone in weeks anyway, I don't want people looking at my HEEOOOOGE tummy and say "ooh another three months eh?" the weeks things befuddles them a bit (unless they are recent mums or pg themselves!)

sugarfree Wed 20-Jun-07 18:48:58

Ds1 I was always weeks + so many days.
Ds2 I was months.
Ds3 I was "dunno,'bout halfwayish?"

MrsMar Wed 20-Jun-07 18:51:33

LOL sugarfree! I've given up with the weeks+days thing, and this is my first! Pregnancy ennui sets in so early!

rhubarb90 Wed 20-Jun-07 18:56:22

I'm counting in weeks because my brain hurts if I try to work out the weird disparity between the 40 weeks / nine months thing. Although it was explained very nicely by designerbaby. I'm 25 1/2 weeks at the moment.

designerbaby Wed 20-Jun-07 18:57:22

sugarfree - I admire your relaxed stance... I hope to get there on day, but damn that OCD...

Do these little darlings ever come when they're supposed to anyway?

asur Wed 20-Jun-07 21:23:46

when anyone asks me, I go with "erm, about 5months" till I decide 6months sounds better. this site has a good thing on the right hand side, if you type in your due date, it works out how many days/weeks/months you are.

PurpleLostPrincess Wed 20-Jun-07 23:11:47

I find this fascinating and confusing at the same time too!

asur, that site looks great - I've put in my details and it actually says:

There are 93 days until your due date on September 22, 2007.
You are 187 days pregnant.
You are 6.1 months pregnant.
You are in your 7th month of pregnancy. (huh?)
Your 1st trimester: December 16, 2006 to March 16, 2007. (0 - 12 weeks)
Your 2nd trimester: March 17, 2007 to June 29, 2007. (13 - 27 weeks)
Your 3rd trimester: June 30, 2007 to September 22, 2007. (28 - 40 weeks)

The 'huh?' isn't me editing, that's the site lol!

BoopaDoopa Thu 21-Jun-07 10:33:53

Thanks to Asur but applause to clever DesignerBaby - that's brilliant!

MrsBadger Thu 21-Jun-07 10:38:24

counting backwards from due date to get weeks is much easier than counting up from EDC.

and use due date (eg 21st) to calculate months

honeyapple Thu 21-Jun-07 10:48:21

ooohhh I like that site asur!

mimicakey Thu 21-Jun-07 12:27:21

designerbaby - that is the best post ever! I am trying to think of something else for you to work out

designerbaby Thu 21-Jun-07 15:14:02

Please don't Mimi! I'm trying to curb my OCD tendencies not encourage them...

I've only just recovered from going Sudoku cold-turkey...

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