Infants conceived through assisted reproductive technology (ART) represented less than 2% of all children born in the United States in 2014, but they experienced disproportionately large shares of adverse perinatal outcomes, according to the Centers for Disease Control and Prevention.
Of the 4.02 million children born in the United States in 2014, a total of 65,296 (1.6%) were conceived with ART procedures. ART-conceived children, however, represented 5.5% of all low-birth-weight infants (less than 2,500 g) and 5.6% of all very-low-birth-weight infants (less than 1,500 g). ART-conceived children also represented 4.7% of all preterm births (less than 37 weeks) in 2014 and 5.0% of all very preterm (less than 32 weeks) infants nationally, the CDC reported (MMWR Surveill Summ. 2017;66[SS-6]:1-24).
These poor outcomes are related, at least in part, to the effect of infertility treatment on multiple births. The percentage of triplets or higher-order infants among ART-conceived infants has decreased since 2000, but “the percentage of twin infants has remained persistently high,” the CDC noted. Multiple-birth infants represent 39.4% of all ART infants but only 3.5% of all infants, and ART-conceived multiple-birth infants represent 18.3% of all multiple-birth infants, the CDC said.
The multiple-birth effect varied considerably by state, however. In Hawaii, ART-conceived multiple-birth infants accounted for 37.3% of all multiple births in 2014, while Alaska and West Virginia both had rates of 5.5%. Poor outcomes also varied by state: In Massachusetts, ART infants represented 14.2% of all low-birth-weight infants, compared with 1.2% in West Virginia. Massachusetts had the highest rate of ART preterm infants to all infants, 13.4%, and Puerto Rico had the lowest, 1.2%, according to the CDC report, which was based on data from the National ART Surveillance System.
Puerto Rico’s rate of 364 ART procedures per 1 million women aged 15-44 years was the lowest in the country, and the highest rate belonged to Massachusetts at 6,726 per 1 million women aged 15-44 years.