Mothers across the country are struggling to find baby formula. With the baby formula out-of-stock rate climbing to 40% last month, parents are worried about finding the next meal for their babies. Beyond the short-term nightmare, this unprecedented shortage could affect parents’ plans for future pregnancies.

Many American babies rely on formula to thrive. According to the Centers for Disease Control and Prevention Breastfeeding Report Card , 19% of breastfed infants born in 2017 were supplemented with infant formula before 2 days of age. That year, less than half of babies were exclusively breastfed through 3 months. Only one in four were exclusively breastfed through 6 months.

The baby formula crisis has rightly risen to the top of the nation’s political agenda. Outside the U.S. Capitol building on Thursday, Republican lawmakers held a press conference on the issue. Rep. Cathy McMorris Rodgers (R-WA) said , “Some families rely on specific formula. I talked with one mom who has a baby with allergies, and it’s extremely difficult. She feels like she’s playing Russian roulette as she goes to the store. President Biden and the FDA must do more. This is a matter of life or death.”

We are only beginning to understand how this shortage is affecting families. A Texas mother shared that she took a day off from work to drive around Texas to find formula, finally buying it an hour away. One of her friends shipped her more formula disguised in wine boxes. For at least one working mother, the shortage is forcing her to choose between going to work and hunting to feed her child.

Most of the current national attention is focused on babies born in 2021 and 2022 who need the formula now — as it should be. But this formula shortage could also lead to longer-term consequences, such as fewer babies next year.

Families decide to use formula for a host of reasons.

One of those reasons is that nursing acts as birth control for many women. This lactational amenorrhea method is found to be 98% effective if the baby is six months or younger and is breastfed without long intervals and the mother isn’t menstruating.

Some mothers decide to stop nursing so that they can try to have more children. Imagine being a nursing mother who hopes to become pregnant again so is considering turning to formula. The baby formula shortage makes that a tougher choice.

Americans don’t need another cost of having more children. With fertility rates at an all-time low , Congress and the Biden administration should take all available actions to ensure parents can access formula, not just for their babies but for the future siblings of those children as well.