DALLAS, TX (NBC) – For expecting parents, it used to be having a boy or girl was left to chance. But not anymore.
Today more people are choosing the gender of their child, a practice that's raising some eyebrows.
The Johnson house in Texas is full of testosterone, with four boys. Four months ago, the "all male" streak was broken. Baby Ava arrived, but not by chance.
"We wanted a girl," Nolana Johnson said. "And we did what we had to do to have a daughter."
The Johnsons went to the only fertility clinic in their state that offers gender selection, the Sher Institute in Dallas. There, Dr. Walid Saleh could almost guarantee them a girl.
Through in vitro fertilization, egg cells are fertilized by sperm in a lab. After three days of growth in an incubator, the embryos are taken out. They are then biopsied, and at that point, doctors can tell how many female and how many male embryos they have.
Comparative genomic hybridization, or CGH, tests all 23 chromosomes in the DNA. Hereditary disorders, birth defects, and gender can all be revealed, allowing the mother to pick which embryo or embryos to transfer back into her body.
"When they called us that morning, they said, 'You have four girls and two boys,'" Johnson recalled. "I was very excited about that."
Johnson said she selected three female embryos to be transferred back.
Saleh said more of his patients want to select the sex of their child, which now accounts for 20 percent of IVF cycles in his practice. Couples pay $10-15,000 for the services.
Tom Mayo, the director of the Maguire Center for Ethics and Public Responsibility at Southern Methodist University, questions the practice.
"I think that the consensus is that it is potentially problematic, that it does raise serious ethical issues," he said. "But the balance so far favors autonomy on the part of the parents in making reproductive decisions that work for them."
Mayo said time often changes minds.
"The technology will move even further, the numbers will increase," he explained. "Our comfort level will probably increase over time, and we'll move on to other issues"
Saleh said he tells people who disagree with his practice, "Number one, I don't make those babies. The miracle of life is the same. They are boys or girls on their own. The only thing we are doing is freezing the boys and transferring the girls or vice versa."
Saleh said he denies people who want a boy or a girl for cultural reasons.
His rule: You must already have at least one child at home. Then you can then select the opposite sex. He calls it "family balancing."
"Through rebalancing, you maintain the 50-50 ratio between men and women," Saleh said. "And I really think that's what's important for society."
Johnson said "choosing" to have a little girl was a thoughtful process.
"I believe in God, and I believe in science, and I think they work together," she said. "I can't imagine anyone looking at Ava and saying, 'This is bad, you shouldn't have done this.'"
Johnson hopes that by talking about her story she isn't judged and that she can help other families who yearn for that girl or that boy.
"If we can help another family, I want to help another family," she said. "This is amazing."