Now, four years later, he was in a hospital intensive care room remembering their courtship as his wife lay unconscious, hooked up to a tangle of machines keeping her alive. Diana was 20 weeks pregnant, and he had a decision to make.

If doctors delivered the baby now, they told him, she would have the best shot at surviving. But the baby was so premature that it would almost certainly die. If Chris waited, he could lose them both.

As the pandemic enters its third year, untold numbers of Americans have agonized over such treatment questions that may mean life or death for their loved ones. Confronting the possible loss of a spouse or life partner is invariably painful, but with covid-19, the severity and suddenness of the illness and the isolation from friends and family has compounded the torment.

The choice in front of Chris was a deeply personal one that only he could make.

Diana was on a ventilator, but her condition was spiraling downward. The coronavirus had thrown her body wildly off balance, and doctors told Chris they needed to move her to a treatment of last resort, in which they would pump her blood through a machine outside her body to take pressure off her heart and lungs. The odds were scary to begin with — an estimated 40 to 50 percent of people going on that machine die — and the baby was putting an additional load on her body that she might not be able to handle.

Chris and Diana were married in the summer of 2019 in a small garden ceremony, and life had been pretty close to perfect since then.

They were opposites, but in ways that complemented each other. Born in Monterrey, Mexico, and raised in North Carolina, Diana was quiet and tended to choose her words carefully. He was a gregarious Texan with a quirky way of recalling dates, numbers and interesting facts about everything from football to legal statutes, a habit that sparked lively conversations with strangers wherever they went. They agreed on conservative values — he was raised Baptist and she was Catholic. And they shared a sharp sense of humor, enjoying shows like “The Office” together.

They had a boy, Cain, and Chris was promoted to sergeant at the Harris County Sheriff’s Office, a job that provided a steady enough income that she could stay home and take care of their blended family. He had two boys from his previous marriage, she had a girl from hers.

The family was young, healthy and happy, and when the pandemic hit, they were worried like everyone else. Before long, though, they started feeling like the dangers of the virus had been exaggerated and they wanted to get back to their lives.

When the vaccines came along, Chris became outspoken against them, espousing views that were common in his workplace and much of Texas, but that put him at odds with his mother, sister and the close friends who had grown up with him in the Heights, a liberal bastion in Houston. Despite pleading from his family, Chris and Diana were adamant they did not need to be vaccinated. They did wear masks, but only when required.

Chris felt vaccine mandates infringed on personal liberties, a perspective promoted by Texas Gov. Greg Abbott and other prominent Republicans. And both of them also worried the shots had been developed too quickly. As Chris liked to say, “God gave us our immune system and we could fight the viruses with our own immune system.” Diana, meanwhile, was leery of anything that might hurt the developing baby she carried. She knew early stories linking the vaccines to miscarriage and infertility were false, but thought avoiding them was the prudent thing to do, like skipping wine, raw fish and unpasteurized cheese — especially given some of the medical community’s early hesitation. The World Health Organization and the U.S. Centers for Disease Control and Prevention now recommend all pregnant individuals get vaccinated.

In the summer of 2021, soon after President Biden declared the pandemic almost over, their two-year anniversary was approaching and the couple decided to go to Las Vegas to celebrate. They stayed at the Trump hotel, walked along the strip and caught a showing of Cirque du Soleil. Diana had a headache, but it didn’t keep them from going out and having fun.

As soon as they returned, however, she developed a low-grade fever and exhaustion unlike anything she had known. Late on Aug. 6, she cried out that she was having trouble breathing. Chris called 911, reminding himself that in his line of work, he’d seen a lot of people go to the hospital for covid — with most recovering fine after a little oxygen.

Diana’s case would turn out to be far less simple.

The emergency doctors at the local hospital immediately transferred her to Texas Children’s Hospital in Houston, which had created a special unit for pregnant people with covid. Chris remembers Diana screaming when doctors told them she needed a ventilator: “I have kids. I can’t die.” He held her and made a promise he wasn’t sure he could keep: “You are not going to die,” he vowed.

From the start, Diana’s case weighed on Cameron Dezfulian, a critical-care specialist supervising or consulting on dozens of pregnancies. “She was unusual,” he recalled.

Most of his other patients had preexisting conditions such as obesity and were close to full-term at 36 to 40 weeks. Diana had been healthy, about 110 pounds, and at 18 weeks when she first arrived at the hospital, still in the second trimester of her pregnancy. She had at least a month before the fetus would be considered viable — a situation that complicated treatment options.

Pregnancy does extraordinary things to the body, and the interaction of those changes with covid is something scientists are only beginning to understand. From the beginning of the pandemic until this month, 27,854 pregnant women with covid have been hospitalized out of 167,000 cases reported to the Centers for Disease Control and Prevention. Many, like Diana, were young and unvaccinated. More than 267 of them have died, making covid-19 a top cause of maternal mortality.

A study of nearly 2,700 pregnant women funded by the National Institutes of Health and published Feb. 7 in the Journal of the American Medical Association found that pregnant women with covid-19 are at greater risk of pregnancy complications — in addition to risks from the virus itself.

Doctors are still baffled about why they get so sick. It could be that pregnancy causes a person’s immune system to be in a heightened state of alert to protect the baby, so when exposed to a virus, it may overreact. Another theory suggests the opposite — that pregnant people are immunosuppressed so that their bodies don’t reject the developing fetuses. Fetuses also pull oxygen and blood to the placenta. When combined with a virus like covid that can cause lung damage and blood clotting, the body’s balance may be upset.

Whatever the cause, Dezfulian said, “there is no doubt pregnancy and the coronavirus are a setup for more illness.”

For Chris, the next 10 days blurred together. He wasn’t allowed to leave the room because he was also assumed to have coronavirus. He’d joke to the doctors and nurses every morning, “I bet you’re tired of seeing me …”

Chris had never lost anyone close to him. And as he stared at his wife and saw her suffering, he couldn’t shake the question that kept popping into his head: “Was this my fault?”

During those long hours alone, he struggled with how strongly he had held to beliefs about the vaccines without really examining them. Increasingly, he felt a responsibility to warn others about his mistakes, so he began writing to friends, family and even strangers on Facebook, urging them to get the shots. Somewhere along the way, he got vaccinated himself.

“When you sit there and you see your wife on life support because of covid, you throw out politics,” he said later. “None of that matters anymore.”

Dezfulian’s team had hoped that the oxygen they were pumping into Diana’s lungs through a ventilator would enable her to fight off the virus. Instead, things were going in the opposite direction. “Every day we were losing a little bit of ground,” he said.

Fourteen days after she arrived at the hospital, the group concluded it was time to move Diana to another machine called ECMO, or extracorporeal membrane oxygenation, in which the blood is pumped outside the body to give the lungs and heart a chance to rest. The decision to put a patient on ECMO is not taken lightly. The therapy, developed in the 1970s, is lifesaving in the right circumstances. But it can also lead to bleeding, stroke, seizure, blood clots and infection. Moreover, the equipment is scarce, the staffing intensive, and the treatment can run up hospital bills in the millions.

At the beginning of the pandemic many people were worried about rationing ventilators, but instead it’s been ECMO that has been in limited supply nationwide. “That is the tough part nobody wants to talk about,” Dezfulian said. “There are a limited number of pumps and you make some decisions on the likelihood they will have a long life and a good life.”

On the day his team recommended ECMO for Diana, a somber trio of staff members appeared in her room to visit Chris. He doesn’t remember the exact words they used, but they seemed to speak in euphemisms. “They would ask how you were” and then throw in a question, like what would he want done if his wife’s heart stopped. “They were giving you hints,” he said.

Chris didn’t fully understand it then, but the staff members were part of the medical center’s palliative care team trained to support very ill patients and their families, especially with end-of-life decisions and care. He said he came to dread seeing them in the hallways: “When you see those people, you pray they avoid your room.”

Chris was worried about putting Diana on the new machine. When he Googled ECMO, he said, he found “it’s a bad, bad deal.”

Using ECMO during pregnancy is extremely rare. One study from the University of North Carolina detailed what happened in nine cases from 2008 to 2017: Only three of the women lived and only five of the babies, for a survival rate of 33 percent and 55 percent, respectively.

He remembers asking a ton of “what if” questions that no one could answer. He kept coming back to something Diana had told him as they shared their childhood dreams. “All I ever wanted to do was be a mom. As a kid, that’s all I ever wanted,” she had said.

So he decided he had to try to save them both. “I didn’t know if one or the other was going to live, or both were going to die,” he said. “I didn’t know if I was going to go back home without anybody.”

Doctors had expected Diana to be on the machine for up to about 21 days. When that marker came and went, Chris told himself to be patient as he stared at the tubes of blood swirling around his wife’s body.

On day 30, it seemed like their ordeal might be over. Diana woke up and was even able to get on her phone and text her family hello. Chris remembers the whole staff smiling and making plans for next steps.

The happy moment was all too brief. It wasn’t long before Diana started seeming confused. Soon, she could no longer see even though she was still talking to Chris. An hour later, she slipped into a coma, and the somber three walked to the room again.

Diana was suffering from “an embolic shower,” in which blood clots burst and scatter, the doctors explained. Three had gone to her brain, causing strokes, and another had lodged in a wall of her heart, resulting in a heart attack. It was a known complication of ECMO, but they had not been able to put her on blood thinners because she had had bleeding in her gastrointestinal tract and in her throat, where doctors had cut a hole for the ventilator.

Now, the doctors told Chris that even if Diana woke up, she might “not be the same,” that she might not remember him or the children. Chris crumpled into the chair next to her and wept. Dezfulian came by and prayed with him.

“That’s when I prayed the most,” Chris said, “because at that point, even the doctors were like, ‘We don’t really know what to do next.’”

Diana went back on ECMO and as the days slowly passed, Chris could see her belly growing. Through everything, the baby’s heart rate held steady and was growing nicely. On Nov. 10, when Diana had been in the hospital more than three months and the baby was 31 weeks along, doctors delivered a baby boy by C-section. He was 4 pounds and 12 ounces.

The infant was healthy. But Diana’s body seemed exhausted from the ordeal: She developed an infection, an air leak in her lungs, and one eventually collapsed. Doctors began preparing for a lung transplant.

It was in this dark moment that things began to shift. Without the added stress of carrying the baby, Diana’s body began to repair itself, and by the end of November, doctors were able to wake her up. She was tremendously weak and at first, didn’t know Chris. His heart felt like it was disintegrating. But then, when a nurse told Diana he was her husband, she pointed to a picture of them on the beach that Chris had posted on the wall and said, “No, that’s my husband.”

Slowly, against all odds, Diana’s memories came back and she began asking about her two other children and wondering how it could be that she was no longer pregnant. She asked Chris, “Why didn’t anybody tell me I was going to have a C-section?”

Shortly before Christmas, on Dec. 23, Diana was able to return home. Chris rattled off the numbers to her: 139 days at the hospital, 101 on a ventilator, 51 of those also on ECMO. She was still attached to an oxygen tank and had three chest tubes in her lungs to keep them inflated, which were pretty painful. But she couldn’t wait to be home.

As soon as they arrived, Chris scooped her up and put her in a bed he and Diana’s father had set up downstairs and Cain, 1, and their daughter, Miranda, 7, piled onto the blankets. Chris cradled their newborn Cameron, plump and healthy, whom they had named after Dezfulian, Diana’s doctor.

One day after they were safely home, Chris finally told her about the choice he had had to make.

She replied that even if things had not worked out the way they did, “I wouldn’t change anything.” He felt relief, but also sadness for all the others who had been in the same spot as him — or would be in the future.

Physically, doctors are optimistic Diana will make a full recovery, but it will take time, and she’s still weak on her left side because of the strokes. Emotionally, she’s struggling. She has anxiety about seeing people and leaving her home for fear of her or her loved ones being infected with the virus.

“Things I used to do before, I can’t do anymore. … And so it’s hard for the kids and it’s hard for me, because you want to do so much more. And they want you to do so much more,” she said.

Most of their extended family who had resisted vaccines has now gotten them after learning of Diana’s ordeal, but a few remained reluctant. In January, they got word that Gilbert, one of Diana’s favorite relatives on Chris’s side who was also unvaccinated, had covid. He was one of the first people Chris had told about Diana, and he was always joking to Chris that he had done well for himself in finding her.

Shortly before Gilbert was put on a ventilator, he sent a video to relatives describing his condition. Diana texted encouraging messages. “God is going to hug you very tight,” she typed into her phone, and sent a video of Miranda saying they were praying for him.

He died in late January, and Diana cried all night.

Drea Cornejo contributed to this report.