http://wiki.answers.com/Q/Can_one_twin_absorb_the_other
Very interesting article. It explains the two different ways a twin can be absorbed and disappear.
http://www.babyzone.com/features/conten ... 525&Page=1
(Exact Quote)
Vanishing Twin Syndrome
By Deborah Bohn The rise in early-term ultrasounds has brought the Vanishing Twin Syndrome to light, revealing that a surprising number of twin pregnancies result in the birth of only one baby.
�We won the conception lottery!�
That�s what I wrote in my online journal when I found out that my husband and I were expecting twins. After months of hormone injections, blood tests, ultrasounds, pills, ovulation test kits and egg extraction procedures, plus a heartbreaking miscarriage, we had finally hit the baby jackpot with the help of a fertility specialist and in vitro fertilization. The ultrasound image at my eight-week check-up showed two shrimp-like embryos and two little heartbeats flashing on the screen. My gynecologist gave me the phone number for a twins support group and told me to get ready for a wild ride!
Imagine my shock and horror when the next ultrasound, a mere two weeks later, showed one fat, wriggly embryo and one tiny bean-shaped one with no heartbeat. We were devastated. Grief stricken. How could this have happened? What went wrong? And what was going to happen to the surviving fetus?
The doctor said I was experiencing Vanishing Twin Syndrome, a common occurrence in the early stages of a multiple pregnancy. I might feel some cramping and possibly a tiny bit of bleeding, but the healthy baby would most likely survive and the �little one,� as we called it, would be reabsorbed by my body over time and simply�vanish.
He was right. Although we were emotionally devastated by the loss of our tiny unborn baby, there was no discomfort or bleeding. My 20-week ultrasound revealed a healthy fetus and an empty amniotic sac, but no sign of the little twin. Our daughter was delivered healthy and on time, but we still think about what it would have been like to raise twins. We still sometimes miss the baby that came and went like a little ghost.