Many doctors, including some who do reduction to a singleton, dispute Evans’s conclusions, pointing out that while twin pregnancies carry more risks than singleton pregnancies, most twins (especially fraternal) do just fine. Dr. Richard Berkowitz, a perinatologist at Columbia University Medical Center who was an early practitioner of pregnancy reduction, says: “The overwhelming majority of women carrying twins are going to be able to deliver two healthy babies.” Though Berkowitz insists that there is no clear medical benefit to reducing below twins, he will do it at a patient’s request. “In a society where women can terminate a single pregnancy for any reason — financial, social, emotional — if we have a way to reduce a twin pregnancy with very little risk, isn’t it legitimate to offer that service to women with twins who want to reduce to a singleton?”

Image Credit... Katherine Wolkoff for The New York Times

Berkowitz gave me a short history of reduction. Perinatology’s goal is to improve pregnancy outcomes, he said. Reduction began as part of that effort: losing some fetuses for the sake of others. But its role evolved into something quite different, as patients requested elective reduction to a singleton. “The only reason we’re the ones doing that is because we’re the ones who have the skills to do it, but that’s not why we got those skills,” he said. “It didn’t start with people who conceived twins and said, ‘I only want one’; it ended up with that.”

Other doctors refuse to reduce below twins unless the pregnancy presents unusual medical concerns. Among them is Dr. Ronald Wapner, director of reproductive genetics at Columbia and another reduction pioneer. Sometime in the late 1990s, when Wapner practiced in Philadelphia, he received his first two-to-one request. “She said, ‘Either reduce me to a singleton, or I’ll end the pregnancy.’ ” He consulted his staff, all women, and they concluded that if a woman can choose to end a pregnancy, she can reduce from two to one. Besides, in this case, the team would be saving a fetus that would otherwise be aborted.

As word spread, a stream of patients called Wapner’s office, scheduling reductions to a singleton. A few months later, after the last patient of the day left, the sonographer who had worked with Wapner for nearly 20 years stopped at his office. She told me what happened next, on condition of anonymity because she doesn’t want her relatives to know everything her work entails: “I told him I just wasn’t comfortable doing a termination of a healthy baby for social reasons, and that if we were going to do a lot of these elective reductions, I thought he should bring in someone else who was more comfortable. From the beginning, I had wrestled with the whole idea of doing reductions, because I was raised in the church. And after a lot of soul searching, I had decided there were truly good medical reasons to reducing higher-order multiples to twins. But I had a hard time reconciling doing reductions two to one. So I said to Dr. Wapner, ‘Is this really the business we want to be in?’ ”

Wapner immediately called a meeting with his staff. Every one of them — the sonographer, the genetic counselors, the schedulers — supported abortion rights, but all confessed their growing unease with reductions to a singleton. “There’s no medical justification in a normal twin pregnancy to reduce to one,” Wapner said. “So we decided to allocate our resources to those who would get the most benefit. We were in the business to improve pregnancy outcomes, and those reductions didn’t fit the criteria.” He hasn’t done an elective two-to-one reduction since.

Evans estimates that the majority of doctors who perform reductions will not go below twins. Shelby Van Voris was pregnant with triplets when she discovered this for herself. After she and her husband tried for three years to get pregnant, they went to a fertility doctor near their home in Savannah, Ga. He put Shelby, then 30, on fertility drugs, and when that didn’t work, he ramped things up with injections. By then, her husband, a 33-year-old Army officer, had been deployed to Iraq. He left behind three vials of sperm, and she was artificially inseminated. “You do weird things when mortars are flying at your husband’s head,” she said. She soon found out she was carrying triplets. Frantic, she yelled at the doctor: “This is not an option for us! I want only one!”

Her fertility specialist referred her to a doctor in Atlanta who did reductions. But when Shelby called, the office manager told her that she would have to pay extra for temporary staff to assist with the procedure, because the regular staff refused to reduce pregnancies below twins. She contacted three more doctors, and in each case was told: not below two. “It was horrible,” she says. “I felt like the pregnancy was a monster, and I just wanted it out, but because we tried for so long, abortion wasn’t an option. My No. 1 priority was to be the best mom I could be, but how was I supposed to juggle two newborns or two screaming infants while my husband was away being shot at? We don’t have family just sitting around waiting to get called to help me with a baby.”