I am feeling pretty alone right now as a plus size woman and TTC through IUI. I have been working on my weight and even lost about 13 pounds in the last 2 months. I started my first round of Clomid today and am feeling scared, fat, and wondering if my size (5'7, 244pounds) if just going to make it impossible for me.
Re: Plus Size and TTC with IUI
I feel your pain!! That was the first thing my RE did was set us up with the nutritionist in their office, and she put us on a strict calorie restricted diet, which is working well for both of us, I find that I have motivation now, that i never had before, knowing that as much as it sucks, we are doing it for a baby, so it makes all the dieting worth it completely.
I'm 5'2 & 230, so i totally feel your pain, and the RE wasn't even willing to start us with anything until i proved that I could lose the weight, so now we've been cycling with estrace, waiting to begin injectibles. He just feels that the more weight I lose, the safer the pregnancy, & the healthier the baby! and i totally agree.
but it sucks because it's a COMPLETE lifestyle change for me and DH.
But it's possible, we can do it
and that's why these board are here, for when we have our bad days...as well as good ones 
Happily Wed DH in May 2010
June 2012: DD#1 born after countless fertility cycles, our 4 year old miracle
TTC #2: current cycle: 225iu Menopur for 4 weeks, Ovidrel Trigger= BFP! Beta #1; 333, Beta #2 713! 1st u/s showed TWINS (7/18)
Let me make you feel better ... I'm plus sized and doing IVF. My first RE recommended losing weight. My OBGYN and my current RE both said that while it would be beneficial for pregnancy that there was no reason to wait for me to lose weight and that we should cycle now. In fact, they both said NOT to diet while we were cycling.
Good luck!!
Our Journey to Brenden
IVF #1: 4/11(Follistim/Menopur/Ganirelix) 10 retrieved/8 mature and all 8 fertilized / 2 embies transferred ... nothing to freeze Beta 5/10 = BFN
IVF Take 2 Long Lupron July 2011
ER 7/3/11 (our 6th anniversary) - 8 retrieved/7 mature/fert ....ET 7/6/11 - 2 beautiful grade A 8 cell embryos
Beta 7/18/11 - 149!!! Beta 7/21/11 - 311 Beta 7/28/11 - 2,000 8/5/11 - Empty Sac 8/8/11 - There's a yolk sac and maybe a heartbeat 8/12/11 - Fetal pole, yolk sac, heartbeat 8/18/11 - Baby looks GREAT!
3 babies waiting on ice
I received very similar advice as KaliChick from my RE and OB and while our IUIs didn't work our IVF cycle did. Just focus on eating right/healthy and taking care of yourself. Now is not the time to crash diet. My docs all said "sure it would be great if I lost 50lbs, but plenty of women who are far heavier than me get pg with no problem everyday so try not to focus on that". And for the record I have had a complication free pregnancy thus far as well and my doc said he wishes all his patients had such an easy time of it. I'm sure being thinner would be better, but being heavy doesn't guarantee that things won't/can't work it.
Good Luck!
Me - DX Hashimoto's Disease, Hypothyroid, Rheumatoid Arthritis
DH - DX Azoospermia - Sertoli Cell Syndrome
DS-IUI #1-4 BFN IVF #1 - BFP! It's a boy!!!