Children — born and unborn — are caught in the crosshairs of an antiquated immigration law.

According to a new Pew report, 40 percent of all births in 2014 were to unwed couples. The share hasn’t been below a third in two decades. Yet immigration law still provides no status for unmarried immigrants who have children with U.S. citizens, separating American families and likely incentivizing abortions.

The law denies U.S. citizens the right to raise their children with the other parent legally here, while ignoring the child’s right to be with both parents. This situation arises whenever an American has a child with a foreigner overseas or with a legal foreign visitor or worker here whose status gives them no ability to stay permanently.

The law’s preference for marriage makes sense. Marriage shows the relationship is intended to be permanent, requiring that the immigrant remain in the country.

But the calculation should change once a child is involved. It is the immigrant’s connection to both the other parent and the child that makes the relationship worthy of legal protection. Even more so than marriage, the birth of the child demonstrates that the parental relationship will be a lifelong enterprise, not a casual undertaking.

Maybe the current policy could have been rationalized a generation ago. In 1940, the Census Bureau tells us, married couples accounted for 86 percent of all pregnancies, and 51 percent of other couples married before the baby was born. By the 1990s, those percentages fell to 47 and 23. This is a problem, but one made worse by immigration law.

Many object to giving visas to immigrant mothers on the grounds that their only connection to the country is in having a child here. But under this limited reform, the other parent would be a citizen. The status would not be granted as a reward for having a child, but to preserve an adult citizen’s rights to raise his child in his own country with his child’s mother legally present.

Unlike awarding legal status to parents of any child born here, this narrow proposal for foreign parents whose co-parents are citizens would not encourage illegal immigration of expectant mothers. Under current law, the child already has citizenship through the citizen father, so there is no additional benefit to rushing the border to have the child on U.S. soil.

It’s the status quo that’s causing illegal immigration of parents. We don’t know how often this happens, but we do know that border patrol apprehended 101,900 parents of U.S. citizen children in 2011 and 2012. If a legal visa were available to those with a citizen co-parent, this flow would drop.

Some will argue that these parents should get married. But this option could be unavailable or inadvisable for many reasons. More importantly, legal necessity doesn’t make a marriage genuine, and using a fraudulent marriage to gain legal immigration status is a crime. If incentivizing fraud is proposed as a solution, that’s just another reason to fix the law.

An additional reason is that the policy is certainly leading to preventable abortions. Nearly half of all abortions are a result of relationship problems or a desire to not be a single mother, according to a Guttmacher Institute study. Congress should remove this unnecessary incentive to destroy life.

No one knows how many of the 53 million children of immigrants were born to mixed-status parents or how many others were forced to abandon a parent in America to stay with an expelled one abroad. The government doesn’t even try to track them. Even if it did, no one could ever count the children who never made it to birth due to this policy.

But immigration attorneys around the country know these situations are common. “Any immigration attorney who’s been in practice for a while would have seen these cases,” says Greg Siskind, a Memphis, Tenn.-based immigration attorney who operates a popular immigration law website. “The lesson is that our immigration rules break families up.”

America today is not the America of 1965, when family immigration law was last rewritten. The world has changed, and if we care about American families and their children — born and unborn — it is time for the law to change. Congress should create a legal way for parents to raise their children together before this outdated policy creates more victims.

This piece was originally published in The Hill.