The New York Times' recent series on "21st Century Babies" provides a distressing glimpse into an unpleasant side of reproductive medicine.
Besides being the Medical Director of Houston Fertility Center, I am a mother -- and one who is especially sensitive to NICU issues. My first-born spent the first week of his life in the NICU.
It was several days before we knew if he would live. Although he was not a twin, I cannot imagine how awful it would be to wonder if two or three of your children would die before coming home, or have long-term sequela.
Because of this heightened sensitivity, and because assisted reproductive techniques have become so finely tuned, I encourage single embryo transfer in indicated situations.
The NYT series, by Stephanie Saul:
The Gift of Life, and Its Price
Grievous Choice on Risky Path to Parenthood
Experts weigh in on the subject on the blog
The Trouble with Twin Births