Cities Turn to Rodent Birth Control: Baltimore’s Success Inspires Washington, D.C.

Urban centers are shifting their strategy in the “war on rats,” moving beyond traditional lethal traps to innovative fertility control. Following a successful pilot program in Baltimore, Washington, D.C. Is now adopting rodent birth control to manage its persistent pest population. This shift represents a move toward integrated pest management (IPM) that targets the root cause of infestations: reproduction.

Baltimore’s Blueprint for Success

Baltimore’s Department of Public Works (DPW) implemented a pilot program using rodent contraceptives from April 2025 to October 2025. The results were positive enough to trigger a city-wide expansion on February 24, 2026. According to CBS News, DPW officials reported a decline in rat activity and a slight decrease in rat burrows within the targeted zones.

As of April 2026, ContraPest bait stations have been deployed across all 14 Baltimore city council districts. These tamper-resistant stations are strategically placed in areas with high rat activity or where the city receives frequent rat-related service calls.

The Science of Fertility Control

The city has utilized different non-lethal products to manage the population:

• ContraPest: Uses the chemicals Triptolide and 4-Vinylcyclohexene Diepoxide to suppress fertility in both male and female rats.
• Evolve™: A palatable soft bait from SenesTech, Inc. Classified as a minimum-risk pesticide by the EPA. SenesTech notes that Evolve is designed to be used within an IPM strategy to provide a sustainable, humane method of controlling reproduction.

Washington, D.C. Joins the Effort

Inspired by Baltimore’s results, DC Health officials are launching a similar pilot program this spring. Washington, D.C. Has faced significant rodent challenges; in 2025, the pest control company Orkin ranked D.C. As the sixth “rattiest” city in the U.S., while Baltimore ranked 12th.

The urgency for these programs is driven by both public health concerns—as rats transmit diseases and parasites—and economic costs. A February 2025 study estimated that the “war on rats” costs approximately $500 million annually, with populations spiking in some areas due to warming temperatures caused by climate change.

A Multi-Pronged Approach to Pest Management

Birth control is not a standalone solution. It is part of a broader strategy that includes aggressive sanitation and traditional abatement.

The “Rat Rubout” Program

Baltimore employs a specialized “Rat Rubout” crew of 16 technicians. This team inspects and treats every alley on a 20-day cycle, a schedule specifically designed to interrupt the three-week gestation period of Norway rats.

Community Prevention

The City of Baltimore emphasizes that sanitation is the most effective way to control populations. Key prevention steps include:

• Secure Trash: Using trash cans with tight-fitting lids (which is required by law).
• Eliminate Food Sources: Removing leftover pet food and animal waste daily.
• Remove Harborage: Clearing old furniture, vehicles, and appliances from outdoor properties.
• Maintain Property: Mowing tall grass and sealing holes in foundations and walls.

Frequently Asked Questions

Is rodent birth control safe for pets and humans?

Products like Evolve™ are classified by the EPA as minimum-risk pesticides and pose no known risk to people, pets, or the environment when used as directed.

How do these programs differ from traditional poisoning?

Traditional methods often rely on lethal baits. In contrast, birth control methods like ContraPest and Evolve™ target the reproductive system to lower the population over time without killing the animal.

How can residents request aid with rat problems in Baltimore?

Residents can call 311 or submit an online service request for the Rat Rubout program. For workers to enter private property, residents must submit a right of entry form.

Looking Ahead

The transition toward non-lethal, fertility-based rodent control marks a significant evolution in urban pest management. As Washington, D.C. Begins its rollout and Baltimore expands its city-wide implementation, these cities are providing a data-driven model for other metropolitan areas struggling with rodent populations in an era of changing climates.