Vegan birth control: What is it and does it work?

As someone on a journey to zero-waste, Kate Hall struggled to find the perfect contraceptive. The packaging of the pill left behind plastic waste, and she was forced to abandon the birth control implant in her arm due to what she called "unmanageable" bleeding.

So the founder of eco-lifestyle blog Ethically Kate turned to all-natural birth control instead. By charting her basal body temperature and cervical mucus consistency, Hall was able to estimate when she ovulates.

Hall isn't the only one opting for this alternative. As of Wednesday, the hashtag #naturalbirthcontrol has over 10K views on TikTok.

Experts say these natural, fertility awareness-based methods are especially appealing for strict vegans who take issue with latex condoms, which contain a milk byproduct, or hormone-based contraceptives such as birth control pills.

"Lactose is in most forms of hormonal birth control and comes from milk," says Elina Berglund, co-founder of the first FDA-cleared natural birth control app, Natural Cycles. "Most of them also go through animal testing before testing on humans, so in that sense it's not totally vegan."

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One major benefit for Hall is the ability to better understand her body. "Not only does this mean you can confidently know the chances of conception are low, but you also find out a lot about your body in the process. It's empowering and helpful."

But experts say it's important to understand the efficacy and potential pitfalls of these non-hormonal methods – and they emphasize these methods don't protect against sexually transmitted diseases.

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What is vegan birth control?

One popular and inexpensive birth control option is the basal body temperature method.

Many people who have tried to conceive are likely familiar with the concept: You chart your temperature every day using an accurate thermometer. A slight increase in body temperature can indicate when you're ovulating, and therefore most likely to get pregnant.

Experts recommend taking your temperature as soon as you wake up — even before getting out of bed. This will be a close proxy to your basal body temperature, or the body's lowest resting temperature.

"If a woman keeps track of her basal body temperature during her menstrual cycles using a special, ultrasensitive temperature tracker, she will be able to detect this subtle rise in body temperature," says Dr. Sherry Ross, a women's health expert and author of "She-ology."

"So tracking temperature daily during several menstrual cycles will allow her to identify the days of the month she should avoid having vaginal penetration sex to avoid getting pregnant."

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However, experts caution external factors, such as alcohol consumption, illness, and even using a heated blanket, can influence a rising temperature.

Similarly, the cycle tracking method involves carefully tracking your cycle. Berglund's app, Natural Cycles, allows users to manually input their body temperature every morning, with an algorithm estimating which days they are fertile.

"The benefit of hormone-free birth control is that you learn a lot about your body and it's all natural, so you don't get those unwanted side effects from options like the pill and it's cost-friendly," Berglund says.

Is natural birth control effective?

In short, experts say these natural birth control alternatives are not as effective as hormonal birth control and condoms. While the Natural Cycles app has a 98% effectiveness rate with perfect use, past research has shown that 24 in 100 women who practice cycle tracking as their primary method of birth control get pregnant within the first year.

"Anything that’s considered 'natural' often boasts a healthier, side effect-free and overall positive vibe," Ross says. "It may be true but one potential consequence is a higher pregnancy rate which can completely derail that positive vibe."

Experts say it is safest to utilize multiple forms of contraception, such as vegan condoms, which have met the same government standards as non-vegan condoms, or the pull-out method. However, unlike barrier methods like condoms, the pull-out method does not protect against STI's or STD's.

"Many women combine the ovulation method with the basal body temperature method to improve the chance of not getting pregnant and minimize accidents," Ross says.

Keeping these caveats in mind, Hall says she has exalted the benefits of combining an array of natural contraceptives.

"Understanding your body, and knowing that you are constantly in a cycle, rather than just on your period one week of the month, has made me feel incredibly empowered," she says. "It has also been liberating to have no extra hormones in my body, so when I feel things, I know they are me - not an extra hormone that I've taken orally."

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This article originally appeared on USA TODAY: Vegan birth control: Basal body temperature method, more explained