INTRODUCTION
Multiple births are much more common today than they were in the past.
According to the US Department of Health and Human Services, the twin
birth rate has increased by over 75% since 1980, and triplet, quadruplet,
and high-order multiple births have increased at an even higher rate.
There are more multiple births today in part because more women are
receiving infertility treatment, which carries a risk of multiple pregnancy.
However, since the first publication in 1998 of the American Society for
Reproductive Medicine’s (ASRM’s) Guidelines on Number of Embryos
Transferred, the number of treatment-related pregnancies with triplets or
more has decreased dramatically. Also, more women are waiting until
later in life to attempt pregnancy, and older women are more likely than
younger women to get pregnant with multiples, especially with fertility
treatment. Although major medical advances have improved the outcomes
of multiple births, multiple births still are associated with significant
medical risks and complications for the mother and children. If you are
at risk for a multiple pregnancy, this booklet will help you learn how and
why multiple pregnancies occur and the unique issues associated with
carrying and delivering a multiple pregnancy.