A site for feral cat caretakers to learn about feline birth control

Update: Feb. 2020


Venivet.com sells

MA/Nonovulin again.


Update: March 2016:


Updated ACCD stance on MA,

fixed dead links, updated  a few things.



UPDATE: March 2015


For veterinarians or those who need more info for their vet:

I’ve added a translated copy of a 2003 French study which concluded  that the risk of adverse side effects of megestrol acetate pills was a miniscule .074 per 100,000 pills sold! See below for viewing or downloading the PDF file. I’ve included the original French language version & my English translated version. Scroll down for more info on the report.

Dear Editor,

 My mommy is a feral cat colony caretaker and she is overwhelmed trying to keep up with “Trap-Neuter-Return” as the litters multiply faster than our funds allow. I have heard of AFFORDABLE & SAFE birth control for feral cat colonies, but the information out there is vague and  some of my veterinary friends even say it doesn’t exist. Could you set the record straight for us?

Does affordable and safe birth control for feral cat colonies really exist?

Love, Virginia

Dear Virginia, please click HERE for the answer to your question.

–Editor, The Sun

Birth Control for Feral Cats...Myth or Miracle?

Check with your local FedEx/Kinko’s & see if they will donate signs for your colony such as the one above.

"The worst sin towards our fellow creatures is not to hate them, but to be indifferent to them. That's the essence of inhumanity." 

                                                                                   ~   George Bernard Shaw


Disclaimer: The information presented on this website is for informational purposes only. Before using any information on this website, please do your own research and consult with a licensed veterinarian BEFORE you use megestrol acetate on any feral cat colony. I am NOT a veterinarian! This website is strictly meant as an informational site only to educate the reader on the possibilities of using megestrol acetate to prevent estrus in feral cat colonies until proper spay and neuter can be performed on the cats by a licensed veterinarian.

Megestrol Acetate has been associated with harmful side effects such as diabetes, pyometra, and cancer. No studies have been able to validate the safe use of Megestrol Acetate even when used at lower doses. This is an off label direction and a potential side effect may be possible and people should use this drug at their own discretion.

Use the information on this website strictly at your own risk!





For veterinarians, ACC&D, and naysayers of megestrol acetate as used for feline birth control:


A Google search of Feralstat or  megestrol acetate as used for feline birth control  always turns up the same old negative statements by the ACC&D for adverse side effects. In 2003 a French study was done on the adverse side effects of MA for birth control. Their findings will indeed surprise you! Any naysayer of MA as a feline birth control needs to read this report. Keep in mind that we are using VERY SMALL amounts of MA  than what was used in the study. I have translated the entire report from French to English. Download a PDF copy of the study HERE. Read it and see for yourself that the adverse side effects of MA is miniscule. Regarding both cats & dogs, the study analyzed medical reports, going back to 1994 which rendered .074 cases of adverse reactions per 100,000 MA tablets administered. That is less than one

case in a million tablets used!