The number of twins being born to American mothers is falling after three decades of increases, according to a recent report from the National Center for Health Statistics. Since 2014, the twin birth rate has declined by 4% to its lowest level in more than a decade, to a rate of 32.6 twins per 1,000 births in 2018.
Beginning in the early 1980s, the number of twins born to moms of all ages and racial groups started a steady climb – increasing by nearly 80% from 1980 to 2014. However, the recent declines have been recorded mainly among mothers age 40 and older, as well as among white women. The rate of twin births among black and Hispanic women have remained basically unchanged over the past four years, the report revealed.
Health experts have connected the past rise in twin births to more widespread use of in vitro fertilization [IVF], which commonly has involved implanting two or more fertilized embryos to help women achieve a successful pregnancy. They also say recent advances in IVF technology now enable the transfer of a single embryo more often, which may help to account for the decline in “twinning.”
According to the report, 123,536 twins were born to American parents in 2018 – still nearly twice the number of twins born in 1980.