SALT LAKE CITY — When Bobbisue Christensen found out she was pregnant with twins, the 31-year-old from Brigham City was excited. Then she got scared.
Christensen and her husband had spent the previous eight years trying to have kids. Three attempts with in vitro fertilization had failed. This would be her fourth try — and now she had to worry about the extra complications of a multiple pregnancy.
In Utah and nationwide, the twin birth rate has reached an all-time high.
Experts say the trend is driven by the popularity of treatments such as in vitro fertilization, as well as more women waiting until they're older to have children.
Twin births have been on the rise for many years. Last year, about 1 in 28 live births in Utah were twins. In 1989, about 1 in 46 live births were twins.
That mirrors national trends. The Centers for Disease Control and Prevention released birth statistics last week showing that about 1 in every 29 babies born last year was a twin. In 1980, that figure was about 1 in every 53 babies.
Dr. Erica Johnstone, a gynecologist and reproductive endocrinologist with the Utah Center for Reproductive Medicine, views the numbers with some trepidation.
Multiple pregnancies — twins, triplets, quadruplets or more — come with more complications than a single birth, including a greater chance of high blood pressure, gestational diabetes and cesarean section, she said. On average, twins are also born four weeks premature and are more likely to have developmental disabilities as a result.
"We in the fertility world have long been worried about this," Johnstone said. "We care for couples going through infertility whose real goal is to have a healthy baby, and there's nothing worse than getting them through fertility treatment and having major obstetric complications."
It’s of particular concern in Utah, where nearly 5 percent of pregnancies were the result of infertility treatment — the highest of the 36 states surveyed by the CDC. According to the report, nearly one-third of twin pregnancies were the result of infertility therapy. More than two-thirds of triplets and higher-order pregnancies were the result of infertility therapy.
But while the twin birth rate has been rising for many years, the birth rate for triplets, quadruplets and higher-order births has fallen.
"That's really encouraging," said Laurie Baksh, a manager with the Utah Department of Health's maternal and infant health program.
That's because as reproductive medicine has improved, doctors have started implanting fewer embryos during in vitro fertilization, reducing the likelihood of risky multiple pregnancies. They are also moving women to less invasive treatments, such as oral and injectable fertility drugs, which pose less of a chance of producing higher-order pregnancies.
About 8 percent to 10 percent of babies born due to oral fertility treatment are twins, according to Johnstone. With injectable fertility medication, the chance of conceiving twins rises to about 20 percent.
In vitro fertilization poses the highest chance of conceiving twins. Statistics show that for women under 35 who use in vitro fertilization, about 28 percent of births are twins, according to Johnstone.
Twins and triplets require more follow-up with doctors and more resources after they're born, Baksh said.
"We want to make sure that women with twins are getting into specialists who can care for those pregnancies best, and if there is a risk concern, that they get to a high-risk specialist," she said.
Christensen knew the risks. Twice already, she had gotten pregnant using in vitro fertilization, only to result in her losing her babies at six weeks. She feared the same thing would happen again.
"It was very hard for both of us," Christensen said. "Each loss just got a little bit harder."
She went to the doctor every two weeks and received ultrasounds at least once a month. They turned up no complications. She passed each milestone.
Then, six weeks ago, Christensen gave birth to twins: a girl and a boy, both healthy.
Now Christensen can’t help but to notice other twins. "I always think to myself, 'I wonder how many tries it took them' or what office they used," she said.
For her and her husband, the statistics are a sign that more parents are getting access to fertility treatment. But they are also a reminder of a lot of hurt and risk the Christensens can now put behind them.
"My heart hurts for everyone who goes into (the in vitro fertilization center) because I know what they're going through, and I know it doesn't get easier," Christensen said. "For us, it didn't. We just kept failing IVF until it didn't seem like there was hope. It didn't seem like things could be brighter. But you just have to keep moving."