The CDC recently released a report documenting the rates and impact of assisted reproductive technology (ART) to multiples, twins, triplets, and higher order infants as well as low birthweight infants and preterm infants.
With the rise of ART procedures, ART-conceived infants now make up 1.5% of U.S. born infants.
Women who undergo ART are more likely to deliver multiple-birth infants than those who conceive naturally because more than one embryo might be transferred during a procedure. Multiple births may place both mothers and infants at significant risk, including pregnancy complications, preterm delivery, and low birthweight infants.
The report found that ART-conceived twin infant rates have remained high over the last decade, whereas rates of triplet or higher order infants have declined. ART use was higher than the national rate in all four states with mandated comprehensive insurance coverage (Illinois, Massachusetts, New Jersey, and Rhode Island).
However, embryo transfer practices were found to be similar to the national rates in all four mandated states.
Regarding birthweight of the infants, ART-conceived infants comprised 5.6% of all low birthweight (<2.5g) infants and 5.6% of all very low birthweight (<1.5g) infants nationally. In addition, ART-conceived infants represented 4.4% of all infants born preterm (<37 weeks) and 4.9% of all infants born very preterm (<32 weeks).
Generally in most states, multiples from ART comprised a substantial proportion of all twin, triplet, and higher-order infants born in the state, and the rates of low birthweight and preterm infants were disproportionately higher among ART infants than in the birth population overall.
Healthcare professionals should continue to support efforts in limiting the number of embryos transferred to single embryo to reduce twin rates, and encourage wider implementation of elective single-embryo transfers, when clinically appropriate, as ways of promoting singleton infant births among ART-conceived pregnancies.
This is also in efforts to help reduce related adverse consequences of ART. In addition, improved patient education and counseling on the risk of twins may be useful in reducing twin births.
For more information call (800) 232-4636 or visit the SMART Collaboration page.