El Paso, Texas - Sayed came into the world in a border detention cell.



His mother, who had travelled from El Salvador with her husband, daughter and 100 others in a truck swilling with urine, had alerted the US customs guard to the pain in her belly. "He said, 'Drink that water, sit down and think about if you want to go to the hospital'," she recalled.

Within half an hour, Veronica's son had been born. The paramedics arrived just in time, but her ordeal was far from over.

After one night in hospital she and her newborn were sent to Tornillo, a holding centre that had recently been opened 40 miles from El Paso to deal with the surge in Central American families and unaccompanied children migrating to the United States .

The white marquees in the cold Texan desert offer temporary shelter for up to 500 people awaiting detention or release. Veronica had been there two days earlier, but had been told that they didn't take pregnant women and sent her back to the border cell.



When Veronica awoke after a freezing night huddled in an aluminium wrap, she noticed that Sayed, who was wrapped in blankets, looked sick. "His little mouth was purple and he was vomiting," she remembered.



They were transferred to the local children's hospital, where Sayed spent 28 days. Veronica said that the hospital staff told her "he probably got a bacterial infection from the conditions he was born in".

Her family was one of the thousands of Central American family units that arrived at the US-Mexico border last year, many fleeing crippling poverty and violence.

Family unit apprehensions reached a five-year high of 77,674 in the last fiscal year, according to US government figures, almost double the previous year's total of 39,838. Arrivals of unaccompanied children rose by nearly 50 percent . The vast majority came from El Salvador, Guatemala and Honduras, the so-called Northern Triangle, where murder rates are among the highest in the world.

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The previously quiet crossing of El Paso, which is in far western Texas and at the centre of the 2,000-mile US-Mexico frontier, has seen one of the most dramatic increases. Refugees have typically favoured eastern border crossings such as McAllen and Brownsville, which are closer to Central America; but in the past federal year family apprehensions in the El Paso sector soared by 364 percent .

Ruben Garcia, the founder of Annunciation House, which runs a network of migrant shelters in El Paso, believes that the opening of family detention centres Karnes and Dilley in southern Texas - Obama's response to the Central American migrant crisis in 2014 - has led families to choose this longer route. "If they want to detain a family they have to fly them there, which is an expense," he said.

Although Tornillo is seen as an improvement on holding families in ill-equipped border cells, Garcia believes that the border authorities are struggling to deal humanely with the challenge that family migration presents.

"The staff on the border and in the crossings bridges are not prepared for what essentially is social work. This isn't detaining people. This is everything that comes with a human person. It's a problem that for us is very serious," he explained.

US Border Patrol released a statement on December 20 praising their quick and compassionate handling of Sayed's birth. But his mother disagrees. "Perhaps if they had called the ambulance the first time I said I'd felt bad, my baby would have been born in hospital. He probably wouldn't be ill." The statement said that the baby had already been discharged, but the hospital confirmed that he was treated there until January 3.

'S tories of humiliation and family separation'

For many along the border, the election of Donald Trump brings added anxiety. The two months surrounding the US election saw a marked increase in arrivals - 28,691 family units were detained in October and November, a 130 percent increase from the same period in 2015. Total apprehensions rose by 42 percent.

Although it's a catalyst rather than a cause, some believe that Trump's promises - a gigantic border wall and aggressive deportations - could be prompting people to cross before it's too late.

"People know that the US is tightening and tightening," said Garcia, who has been helping migrants along the border for nearly 40 years."They saw what happened in 2014." After declaring a humanitarian crisis, the Obama administration kept some women and children detained for more than a year . The policy was intended to deter others.

For Veronica, it was a combination of losing her job and worsening gang violence at home that pushed her to make the journey. "We were already on the way when we found that Trump had won. He makes you afraid, but going home would be even worse."

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Many fear the incoming president's stance will be even harsher than Obama's, who deported more than any other president in US history. "We wonder if he's going to ask Congress to appropriate money to open up more family detention," said Garcia. "So instead of 3,000 beds, we have 10,000 for mothers, fathers and children."

Family detention in the US continues despite ongoing controversies . In July 2015, a federal judge in California found that the detention of children, both with and without their parents, violated a landmark 1997 ruling on childcare standards. Yet Immigration and Customs Enforcement ( ICE ) still detains families and children until they take the "credible fear interview" - the prerequisite for successful asylum.

"If you come and in and say to me the magic words 'I am afraid', you're automatically in a credible fear track," explained Garcia. "If you say to me, 'My children are not eating and I have to find work to feed them', there is no provision in law. It's very sad how this whole thing works."

The difference between detention and release is often arbitrary, said Garcia, depending on numbers and space. He recently received a phone call from ICE asking him to take in 164 women and children who were on a plane at El Paso airport. It was bound for the family detention centres, but a child had contracted chickenpox and the facilities refused to accept anyone for fear of an outbreak. Eventually, one centre relented and took half - the other half was released.

"To them I said, 'From now on, when you make the sign of the Cross you say, 'In the name of the Father, the Son, chickenpox, Amen'."

Annunciation House runs three temporary shelters for the fortunate ones, who have been released by customs with a court date, often in a year or two. One hundred and seventeen women and children have just been dropped off in three bus loads from Tornillo. Here they can wash, eat and sleep before continuing their onward journey. Within a night or two they're on their way and a whole new set arrives, many exhausted or desperate, their first taste of the US a long way from the American dream.

US Homeland Security Secretary Jeh Johnson has recognised unaccompanied children and families as a "new challenge" in the immigration system, writing in October of his department's determination to treat migrants humanely. But speaking to those in the busy shelters on the border, stories of humiliation and family separation are common.

Casa de Migrantes

On the other side of the frontier in Juarez, Mexico, Casa de Migrantes attends to men, women and children en route to the US, or those who have already been sent back. Many are single male Mexicans being deported to their home states.

In a quiet, private bedroom, three-year-old Alejandra* tugs frantically at her mother's sweater, pulling up the fabric to try to wipe away her tears. She's just a toddler but she's hot-wired to her mum's feelings.

The pair fled their hometown in El Salvador after witnessing gang members shoot dead a policeman. He was her husband's cousin and it was the third police killing in the country that week. The day after the officer had been buried, a man came to her door and handed her a mobile phone.

"He said, 'You have 24 hours to disappear. If not, you and your daughter will no longer exist'," Cristina* recalled, crying. She fled to her sister's house and called her brother in California, who got the money together for her journey.

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But when she finally arrived at the border to ask for asylum, her pleas were ignored. It was a Saturday.

"She [Alejandra] was saying, 'Mister, please let Mummy and me pass'. They didn't pay attention and turned their head the other way," said the 26-year-old.

"They just said, 'Go back. It's closed. Don't you understand? Have you never been to a shop? Come back Monday'."

"We said that we didn't have anywhere to stay, that I was asking for asylum. Then the other man said, 'Not now, not Monday or ever are you getting into the United States'."



US Customs and Border Protection spokesman Roger Maier told Al Jazeera that the border ports are not closed to people seeking asylum "at any time". Individuals were advised to return the following day if capacity had been reached to allow for a "safe and expeditious process", but since the opening of Tornillo this is no longer in effect, he said. Cristina's case occurred three weeks after the opening of Tornillo.

Bystanders on the bridge told Cristina about the shelter, where she has received meals, a change of clothes and a bed. She planned to head back to the border early the next day, this time via another bridge.

"We're afraid they won't give us asylum. I can't go back to El Salvador," she said.

The International Women's Media Foundation supported Sophie Eastaugh's reporting from the US-Mexico border as part of the Adelante Latin America Reporting Initiative.