Assisted reproductive technology in fertility services behind increased multiple births
By Lee Hae-rin
On New Year's Day this year, Ahn Ki-hoon, a professor of obstetrics and gynecology at Korea University Anam Hospital, carried out a cesarean operation to help a pregnant woman deliver triplets.
"It was a very close moment to birth," Ahn told The Korea Times in a recent phone interview, explaining that the mother was going through premature contractions in the 33rd week of pregnancy. With the help of a pediatric doctor, an anesthesiologist and Ahn, the mother delivered three newborns, all healthy and well, despite the high-risk conditions.
Ahn's hospital is one of the four high-risk pregnancy medical centers as designated in 2019 by the Ministry of Health and Welfare, and it runs a specialized geriatric pregnancy clinic for aged mothers in the northeastern part of the capital.
The doctor said he has witnessed a rise in multiple births in delivery rooms and neonatal wards in recent years, commenting that the increased multiple births is a social phenomenon proven by demographics.
According to Statistics Korea's latest figures released on Aug. 29, about five out of 100 babies are multiples. 5.4 percent, or 140,000 of 2.6 million newborns brought in Korea last year were multiples. That includes 136,000 twins and 500 triplets, taking 5.2 and 0.2 percent of the total babies, respectively.
By decade, the country's twin rate has been steadily on the rise. The peak, however, was reached this year, as the figure grew slowly from 1990's 1 percent to 2002's 2 percent, and finally surpassed 5 percent last year.
The state statistics office and experts point out that the country's twins boom is the result of postponement of parenthood and increased use of assisted reproductive technology in fertility services. On average, twins' mothers are 34.8 years old, 1.5 years older than other mothers.
Their correlation is also apparent in differing twin birth rates shown by mothers' age groups ― the percentage is overwhelmingly higher among mothers aged between 35 and 39 at 8.1 percent, compared to 2 percent to 4 percent among younger age groups.
Multiples have grown more visible outside hospitals and statistics as well.
Actor Song Il-kook and his triplets ― from left, Song Min-kook, Man-se and Dae-han / Korea Times file photo
In 2014, actor Song Il-kook made a sensation with an appearance on KBS parenting variety show with his triplets, Dae-han, Min-kook and Man-se, whose names together make up the phrase "Long Live the Republic of Korea." The family gave a fresh shock to the public and soon became everybody's favorite triplets. Followed by Song's three sons, twins of other celebrities, including comedian Lee Hwi-jae and former K-pop diva Yoo Soo-young have appeared on media.
The market started to see a diverse range of nursery products devised to facilitate multiple childcare. Not just matching outfits, but almost anything, including baby strollers, pillows and bottle-feeding stands for twins became widely available.
Historically, populations have seen a rise and fall of twin births immediately after wars or revolutions. However, researchers agree that the recent boom is a global phenomenon seen in developed countries over the past four to five decades.
Twins from all over Greece take part in the first nationwide gathering of twins, in Trikala, northern Greece, Sept. 22, 2019. EPA-Yonhap
Since 1980s, global twin birth rates have increased by a third, from nine to 12 twin deliveries per 1,000 deliveries, according to a 2021 report published in Human Reproduction, an Oxford Academic peer-reviewed journal in obstetrics, gynecology and reproductive biology. The report said 1.6 million twins are born each year worldwide, which is about one in every 42 newborns.
The common denominators in transnational phenomena are introduction of hormone treatments and in vitro fertilization (IVF) and increased age of mothers ― the effect of the former is three times stronger on average than the latter, according to a research published on Population and Development Review in 2015.
In Korea, the two factors are intertwined, as more women have entered into the workforce, postponed motherhood and naturally grown more reliant on medically assisted reproductive technologies, according to Hur Yoon-mi, a professor at Kookmin University who heads the Kookmin Twin Research Institute.
According to Hur's research published last year in Twin Research and Human Genetics, a bimonthly scientific journal published by the Cambridge University Press, Korea's traditionally low twinning rate has not only surpassed the global average but now ranks among the highest, doubling the average.
The change could come as a surprise to the country where twins had rarely been seen before. However, multiples are, despite their distinct genetic similarities, separate individuals who are not too different from singleton babies in social behavior.
"The twins rather tend to feature higher sociability and self-esteem … and as their number went up, the younger generations have grown keen to them," the professor said, explaining that twins and multiples are easily found in today's kindergartens and elementary schools, and many children want to get to know their similar-looking peers.
Experts believe that multiples could offer unique and valuable contributions to society. Ahn, who also formed and leads a research group at Korea University to study the low birth rate, and Hur both underscored their potential role in tackling the country's declining birth rate.
Identical twin sisters Verna, third from left, and Viola Mueller, fourth from left, from Lancaster, Pennsylvania, who were born on Valentines' Day in 1933, take part in a themed dress competition during the annual Twins Days Festival in Twinsburg, Ohio, Aug. 4, 2007. Reuters-Yonhap
"That is why we need more education and health policies for twins," Hur said, giving an example of childcare funds and class placement systems for multiples in early education, as children grow emotionally independent and self-reliant at a young age.
Moreover, twins studies worldwide have "greatly contributed to understanding the human mind and correlations between genetics and environment in forming personality, intelligence and physical and mental traits," Hur said. "I hope more twins and multiples in Korea come forward and participate in the research for the development of science and society."
Hur added that in countries with a large population of multiples, twins and multiples festivals are held to celebrate their identity and unique contribution to the community. "Hopefully the day will come for us too, when twins are widely accepted and celebrated," the professor said.
