TEHRAN – Since the beginning of this year (March 21), 9097 cases of multiples have been born in the country.

Over the past six months, 541,452 infants have been born, of which 522,933 were related to single births and 18,519 were related to multiples, IRNA quoted Seifollah Aboutorabi, the National Organization for Civil Registration spokesman, as saying on Friday.

Out of 9,097 cases of multiple births this year, 8,788 were related to twins, 294 to triplets, 14 to quadruplets, and one higher-order multiple births, he added.

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 percent since 1980, and triplet, quadruplet, and high-order multiple births have increased at an even higher rate.

There are more multiple births today, partly because more women are receiving infertility treatment, which carries a risk of multiple pregnancies. 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 notable 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.

FB/MG