The Bill & Melinda Gates Foundation has made headlines after providing a US$5 million grant to help researchers at the Oregon Health & Science University create a long-lasting form of birth control that doesn't require surgery.

According to the foundation's grant announcement, the funding will be used to "develop additional safe, effective, acceptable and accessible methods of permanent or very long-acting contraception that will fill an unmet need for women who have reached their desired family size and do not wish to become pregnant again".

It's pretty awesome news for women who've had as many children as they want and either have to take the pill every day, use condoms, regularly rotate hormonal implants until they hit menopause, or convince their partner to get a vasectomy. But the grant has been met with criticism from pro-life organisations because of concerns that such a long-term form of contraceptive could be used to control who does and doesn't reproduce.

Jeffrey Jensen, a gynaecologist who leads contraceptive research at the Oregon Health & Science University in the US, refutes this claim. "My goal is very simple: to make every pregnancy planned and highly desired," he told Elizabeth Hayes from the Portland Business Journal, citing a study that found half of Ugandan women no longer want to become pregnant, but only 2 percent can access permanent contraception.

Jensen is currently testing whether an FDA-approved foam that's used to treat varicose veins could also work as a long-lasting contraceptive, and so far results in primates studies look promising. His group has also just finished accepting applications from researchers around the world to explore other ideas for contraceptive technology.

This isn't the only long-term solution Bill and Melinda are looking into. Last year their foundation announced that they had provided US$6.7 million in funding to tech company MicroCHIPS to develop a remote-controlled contraceptive implant. The implant turns on and off the release of contraceptive hormones, and can last up to 16 years, essentially eliminating the need to take daily pills or change implants every few years. The device is expected to be on the market by 2018.

"The ability to turn the device on and off provides a certain convenience factor for those who are planning their family," Robert Farra, president of MicroCHIPS and a researcher at MIT, told Dave Lee from the BBC last year.

The chip, which measures just 2 cm x 2 cm x .7 cm, works by delivering around 30 micrograms of birth control hormone levonorgestrel into the bloodstream every day via a small electrical charge - but it can be switched on and off at any time, allowing the user to control when they get pregnant.

While the implantable delivery technology is ready to go, the researchers are now working on making sure the system is secure.

"Someone across the room cannot re-program your implant," said Farra. "Then we have secure encryption. That prevents someone from trying to interpret or intervene between the communications."

The Gates Foundation aren't just focussed on women, either. They're also donating money to the development of a condom that actually feels good, as well as looking into ways to get male chemical contraceptives on the market.

After 55 years of an industry dominated by the contraceptive pill, we're pretty excited that science may finally be on the verge of providing some much-needed options to allow women to take control of their reproductive choices.