Here is a month by month tip sheet for making the life of your pregnant wife/girlfriend/whatever a little sweeter. Doing these things will serve you well: if she knows you appreciate the "shape" she's in, you'll hear a lot less whining. Everybody wins!
Month One: Go to the bookstore and buy Pregnancy for Dummies. It is by far the best quick reference book, (more like a user's manual for your uterus). It's straightforward, filled with easy to understand facts, and I used it all the time. There are lots of other titles out there (here's a link), but I found Dummies the best. It's really fun to read, too. You can go crazy and buy a few if she likes to read.
Month Two: Morning sickness sucks. It can strike anywhere, at any time, and for some women, it's an all day event. Make sure there are saltine crackers and ginger ale everywhere (or whatever makes her stomach feel better). Make sure she always has them at her bedside table, her car, her purse, the bathroom. Other things that can help morning sickness: sour lollipops (Preggie Pops or Queasy Pops can be found on line here), peppermint, and fresh ginger.
Month Three: Tell her she looks beautiful. She may be starting to show, or she may just be looking a little pudgy. Either way, it's really nice to hear from your man that he finds your expanding body beautiful. This should actually be done throughout the pregnancy. If she is gaining too much weight, her doctor will have no trouble letting her know, (it's a danger to her, and your baby). You are off the "do I look fat?" hook for the duration of the pregnancy.
Month Four: Buy her a frame for your first ultra sound picture. I still have both my babies' ultra sounds on my bedside table. I love them, and will have them forever.
Month Five: I had crazy cravings during my pregnancies. Not crazy like pickles and ice cream, but cravings so strong I couldn't control myself. One night, my husband was out playing basketball. I called him and told him if he couldn't find watermelon for me, not to bother coming home. Running out of Krispy Kreme doughnuts would bring me to tears, literally. So, indulge her, she's been possessed, and she can't help it.
Month Six: Plan a little get away if you can. This is a time when she is feeling good, not too big, and has energy. It is a great time to enjoy some time alone, as a couple, before your life time role of parent begins. (Most airlines will not allow a pregnant woman to fly after 32 weeks).
Month Seven: Indulge her when she says she'd like to take a Lamaze class. Go with her, do the silly breathing, the whole thing. I can tell you I did not use one single thing I learned in Lamaze while I was in labor, but I have some of my favorite memories of my husband and me in that class, laughing hysterically at each other.
Month Eight: It's probably been a little while since she's been able to see her feet. Help her tie her shoes. Then, buy her two pedicures at her favorite spa. One for her, one for her best friend. Then send them on their way. She can complain to someone else for an hour about how fat she feels. You don't have to hear her, and you look like a great husband.
Month Nine: Two words--pregnancy massage. Find someone who is licensed in pregnancy massage and who will come to your house. Schedule the massage in the evening. Turn of the phones, light candles, put on soft music. Just when she thinks you've lost your mind because there's no way in hell she's having sex with you, you tell her she's having a massage, and that she can literally roll off the table and into bed to go to sleep for the night. You are leaving her in peace and quiet (aka, you are going out with your friends). Again, you look like the hero while you are out having a beer.
Month Ten: Honestly, men, by this time do whatever the F she wants. She is beyond uncomfortable, can't sleep, and she is emotional. It's going to be a very rough last few weeks on her, and the next thing she has to do is cram that kid through her you know what, and you don't. So, suck it up, and be at her beck and call. It's good practice, cause you'll be at your newborn's beck and call any day now, and loving it.