If you can postpone a trip, I'd say do it. But if you are going to go, go as soon as possible. I just went back and looked at my diary. At 20 weeks I looked and felt 8 months pregnant. At 24 weeks I was horribly uncomfortable and tired. I seriously think you will be miserable if you go anytime after 20 weeks. Besides, at that point, you are getting dangerously close to when many twins pregnancies start preterm labors. Have you talked to your doctor?
" I object to violence because when it appears to do good, the good is only temporary; the evil it does is permanent." Mahatma Gandhi
"This is the ultimate weakness of violence: It multiplies evil and violence in the universe. It doesn't solve any problems." Martin Luther King, Jr.