Husband has trouble getting hard.
My husband and I have been having what I consider a "dry spell" Maybe once a week.. . .sometimes two. Sometimes he will have trouble getting hard, or staying hard. He is only 29 years old. He did see a doctor and they ran some blood work but everything came back normal. The only test elevated was his cholesterol. Yet, he is healthy. He is 29, 5'10 and 170. He actually has trouble keeping weight on. I cant help but feel, this is directed towards me. I'm very fit. 5'4 120 and try to look attractive for him. I always try to look nice when he gets home from work in hopes he'll want me. .. but he hardly notices. WHAT THE HECK!!! I've even put on SEXY little outfits, and hardly get a head turn. I dont get it. We have two babies, and the only thing I can think of is my boobs have shrunk after breastfeeding for close to 4 years straight. They went from a 36c to a 32B. They bother me, but I cant see this as the reason for his problem.

I'm not an expert but my guess would be more focused on the mental rather than the physical. Stress or fatigue can really impact your sex life. How are things in that area? How is his job, family, home responsibilities, etc. going? While looking nice when he comes home is great, maybe he is really looking for someone to talk to and connect with. Then, the sex will naturally follow.
Good luck.
Sometimes when a man has trouble keeping an erection it makes him very anxious about next time. He worries about "failing" in sex and therefore he starts to avoid sex altogether. Thats why it is especially important to address this right away. Using a medication to maintain an erection temporarily can give him the confidence he needs to resume sexual activity and feel desire rather than anxiety.
Talk to his doctor about checking his testosterone level, just to be sure this is not the issue, and then about a medication for the short term.
Also, TALK to him about how he is feeling. Is he stressed with work, the kids, financial responsibilities? Stresses effect sexual functioning. Feeling supported and understood by you could be more helpful in maintaining an erection than the newest sexy outfit. Tell him you want him and that sex is important to you. If neither of these work, consider seeing a certified sex therapist.
First just to clarify a myth, studies have shown that heredity, number of pregnancies, skin elasticity and weight are actually more to blame than breastfeeding for smaller boobs post baby. Not that it makes it any better, though -- believe me I breastfed for about 5 years altogether and I guess I've got saggy genes because these puppies hang low! It can be a hit on the self esteem, but of course the kids are totally worth it, and I invested in some really nice bras and camis with built in support that I often wear to bed. (Though they never stay on -- it seems to bother me more than my husband!)
Also - I think we women often misjudge the pressure guys feel when they become dads. This worry and anxiety can really affect them -- in bed and out. Add to that the cycle of anxiety around sex that Gail mentioned and I agree it's so important to start talking about the stress he may be under.
Similarly, many dads have a hard time adjusting to seeing their wife or girlfriend suddenly in the "mother" role. Make time for the two of you to get out of the house and away from all things baby so he can see you in that fun carefree light again sometimes. Taking care of your appearance is a great way to nurture your own sexiness. But also make sure you're keeping each other's heads in shape too....Start by saying something like, "Wow, I've changed so much since having the babies, sometimes it's hard to remember I'm more than just a Mommy. Have you ever felt that way about being a dad?" You might be surprised what he has to say.
No one seems to ever mention this when I see similar posts on other sites, but I have a bit of a problem in this area myself. I have what I believe to be an addiction to porn. My wife knows about this, and it is against our beliefs and religion. I believe this causes me a lot of guilt and anxiety. When I have been looking at porn, I often feel guilty and this causes problems with me having an erection. I have also read and heard that the guilt from having an affair can also cause erection problems.
I highly doubt his difficulty getting hard has anything to do with your physical appearance. As the other have suggested it's most likely something going on with him be it stress at work, stress as a new father etc.
He is under alot of stress right now and working very long hours. I'm a stay at home mom and take care of everything besides the INCOME!!! I ask nothing of him when he walks in the door because I know how much weight is on his sholders right now to get through his training. We do talk about life, his work, my day, his day etc. We ALWAYS have dinner when he gets home and them he is off to studying and I get the kids to bed. This problem however began about 6 months ago. He did have stress then but not as much. I would say an affair maybe, but he is far too loyal of a person. He is very trustworthy and has always been the one to stress no straying and being honest. We have talked about this issue and he says that when it does happen, his body feels turned on, yet nothing happens. He is a bit embarrassed about it, but has seen a doctor just to get no answers. I think we are both frustrated and confused. I know he wants sex as much as me, but hates when this happens occasionally.
The mind is a powerful thing, particularly in the realm of sex. Sometimes the fear of losing your errection can cause just that to happen.
I don't know if it makes sense or not but perhaps he could try some type of herbal remedy. The experts may be able to suggest something suitable. Even if there is really nothing to them if he believes they will work then thats likely just as good.