In the past decades, the number of twin births has skyrocketed. A new study shows that triplet births — including those conceived without the help of reproductive technology — are also on the rise.
Researchers in Norway looked at 2 million births in that country between 1967 and 2006 and examined all live births and stillbirths after the 16th week of gestation. What they found was a rate of triplet pregnancies 2.5 percent higher now than in the 1970s. Results of the study were published in BJOG: An International Journal of Obstetrics and Gynaecology.
The highest rate of triplet births, including those which were the result of IVF, was between 1987 and 1991 — before regulations began limiting one embryo transfer at a time.
Researchers attribute today’s higher rate of what they call “natural” triplets births to increased maternal age and an increase in the use of ovulation stimulating drugs.
Also high is the death rate for triplet births, which is nearly 10 times higher than that of singleton births. But the study showed that triplets fare dramatically better when allowed to gestate beyond 28 weeks.