Why I desperately regret putting all my faith in a ‘natural’ contraception app: Like many of my generation who’ve turned their back on the Pill, I trusted an ‘officially certified’ fertility tracker – with heartbreaking consequences

I was sitting in the bathroom in my pyjamas when I saw the two blue lines appear on the pregnancy test. 

For a moment, everything seemed to blur. I picked up the instructions, reading and rereading them, willing them to tell me something different. It didn’t make sense. I couldn’t be pregnant — I’d been so careful with my birth control. A wave of shock rose from my stomach, tightening in my chest.

What surprised me most was the feeling that followed: a deep, instinctive longing for the baby I hadn’t planned. 

It was completely unexpected, and I knew in that instant I was facing one of the hardest decisions I’d ever have to make — to keep the baby and embrace the idea of becoming a mother by accident, or to walk away from it.

I texted my boyfriend, heart pounding.

I was 26, and the fact I’d fallen pregnant without meaning to made me feel naïve and foolish. Before that moment, I’d considered myself perfectly responsible when it came to my own fertility. As a qualified sex and relationships coach with a large social media following, I had always educated myself and knew more than most about the issues involved.

And yet now I suddenly realised with a sickening jolt that the contraception I’d been using for the past two years – the fertility tracking app Natural Cycles – had left me vulnerable to unplanned pregnancy.

The truth is, many women my age — if not most — are keen to come off the Pill, and if there’s an alternative that’s just as reliable, they’ll take it. That’s what I thought Natural Cycles was.

I took the Pill when I got my first boyfriend at the age of 16. After two years of it, however, I began to feel the side effects more intensely: mood swings, excessive bleeding between periods and constant bloating. I switched to the mini pill, which worked better for a couple of years. But after nearly seven years on hormonal birth control, I decided to take a break.

The change was staggering. It felt as though a fog was lifted and suddenly my brain was switched back on. I broke up with my boyfriend of six years and felt a new sense of freedom. I even left my job in marketing and started posting on TikTok and Instagram, building a substantial following as I trained as a sex and relationship coach.

Like many of my friends, I first came across so-called fertility apps via adverts on social media platforms. Femtech is big business online, with apps such as Flo, Clue and Ovia helping women to track their periods or conceive. But none of these claim to enable women to control their fertility like Natural Cycles. Indeed, it’s the only one officially certified as a ‘contraceptive device’ in both the US and Germany.

Claiming to be 98 per cent effective with ‘perfect use’ (ie. where you don’t have sex on days you’re not supposed to) and 93 per cent effective with ‘ordinary use’ (allowing for a few slip-ups), Natural Cycles appears to be the holy grail of contraception: a natural method with roughly the same success rate as the Pill or a condom.

Now I had a thriving TikTok account, I was offered a free trial (it normally costs £49.99 for a one-year subscription). I was never paid by the Natural Cycles team, but a request was made that I talk about the experience of the app online.

At first I was excited. Created in Sweden in 2013 by Dr Elina Berglund, a Nobel Prize-winning particle physicist, the app certainly comes with stellar scientific credentials. It works by monitoring your temperature, which you input each day and which fluctuates throughout your menstrual cycle. Using your data, the app then trains its clever algorithm and starts to predict when you’re ovulating and, therefore, when it’s safe to have sex. Or not. ‘Green days’ are fine; ‘red days’ are not.

I was cautious at first. I knew it took three months to calibrate the data, and in the beginning I always used condoms too, just to be safe.

But over time I grew more confident in its abilities. It certainly helped me better understand my body and this was the aspect I wanted to talk about online.

And then, a year into using Natural Cycles, I started a new relationship and, call me paranoid, but every few months I’d take a pregnancy test for peace of mind. It wasn’t required by the app, but it helped me feel more secure, especially if stress caused a delay in my period.

I’d been using the app ‘perfectly’ when it happened. Eight days late, I was ravenously hungry and yet I was absolutely certain I wasn’t pregnant. How could I be?

When I told my boyfriend, the silence on his end of the phone stretched for what felt like hours. Now sitting on the bathroom floor in floods of tears, I definitely needed him to say something, anything… but he was just as shocked and confused as me.

The truth was, a small part of me did want this baby, right there and then, with my boyfriend. That quiet, aching possibility was hard to shake. But my uncertainty, I think, made him nervous, and I knew he was desperately unsure.

The next day, I booked a scan with the British Pregnancy Advisory Service (BPAS). We had to drive an hour to Chester to have it done, and the car ride was tense, heavy with things left unsaid. The staff there were kind and gentle and saw me alone to check I wasn’t being ‘pressured’ into having an abortion.

Well, was I? Not by my boyfriend, though we hadn’t had a chance to talk properly, but perhaps by what society expected of me. I wasn’t long out of full-time education, I had a thriving new business online, and ‘single mum by accident’ wasn’t on the career plan.

You’d have thought seeing the image on the screen during the scan – the tiniest of smudged tadpoles – might have clarified matters, perhaps softened me to it. But what it did was make me angry. Furiously so.

Recording my temperature and tracking my cycle every day in total faith for two years hadn’t worked. I felt completely betrayed. I was now in a situation where I had to make an impossible decision that would have a profound effect on my body, my relationship, and my future.

Yes, I felt an instinctive protectiveness over this thing inside me, but the reality was we weren’t ready yet. My boyfriend wasn’t ready yet. We weren’t living together. We weren’t married. We had only been together for a year and our lives weren’t the right shape. As he bluntly put it: ‘That’s why we weren’t trying.’

The fact is I desperately wanted him to want the baby with me, but the traditional values that his family unholds definitely weighed heavily on his perspective on parenthood.

Rationally I understood where he was coming from – but emotionally I knew what I needed, and that wasn’t it. I knew he felt blindsided and I was sorry, but it was my body and, fundamentally, my future at stake.

The BPAS counselling service helped me to clarify my thoughts, and in a sense shattered my dreams. Once the realities of single motherhood were spelled out, I knew I’d struggle at this stage of my life.

But still I couldn’t end it.

Two weeks later, the clock ticking, my mind still a whirl of uncertainty, I had to have a second scan because the doctors were worried the pregnancy could be ectopic.

This time my boyfriend came in with me to the scan, and this time you could see the baby’s heartbeat. I looked over at his shocked face and felt a huge sadness. I knew then I was going to have an abortion.

When I mentioned using Natural Cycles, the nurse laughed and said she had used it as her contraception and now has two kids.

I didn’t take the print-out of the scan, but I did take a picture of it on my phone. It felt like the end of something monumental, a part of my life I’d never forget.

The clinic had a slot the following day, and I arrived to pick up the pill you take 24 hours before the surgical procedure, barely able to speak through my sobs. I took the pill and sat in the front seat of my car, alone.

And then I felt… relief. I still don’t know why. Somehow, once I had made the decision, once the uncertainty was no longer hanging over me, I could think more calmly.

The next day my boyfriend came with me for the surgical abortion.

The clinic was quiet, a small, unassuming building with no protesters outside. My stomach was in knots as I walked into the sterile room, where eight doctors stood around, waiting. I sat on the chair, placed my feet in stirrups, and tried to answer their questions between tears. They asked me at least four or five times if I was sure.

Then the nurse placed the gas-and-air mask over my face and a haze settled over me. The anticipation, the waiting, the uncertainty — it all came down to this single, surreal moment, lying there, dazed, and spread out on the table.

And yes, I felt better afterwards. Not euphoric, not light-hearted, but perfectly okay. The sense of loss I had braced myself for didn’t crash over me, not right away.

The hardest part, in fact, wasn’t the procedure itself — it was the other women. Sitting there, surrounded by people in various stages of grief, while still trying to process my own, was something I’ll never forget. Their tears mirrored my own, and for a moment, I felt the enormity of the collective sadness in that room.

Still, I knew it was the right decision.

I changed back into my clothes, shaky but steady, and returned to the waiting area where the nurses were looking after all of us. One of them tried to lighten the mood, asking me what I did for a living. When I told her I was sex and relationships coach, we shared a laugh — an odd, fragile moment of normality in an otherwise surreal day. But beneath it all, a faint curl of shame lingered, refusing to loosen its grip.

We went home, and aside from some cramping, I had no physical side effects. The emotional repercussions, though, were harder to unpack. Having spoken openly on TikTok and Instagram about using Natural Cycles, I suddenly found myself having to make another significant decision.

Should I share this part of my story or keep it to myself?

In fact, I’ve never gone into detail about my abortion online, but I have been transparent about the unreliability of Natural Cycles. And what’s surprised me most is the outpouring of support from my online community.

One moment in particular stands out. I posted a video: a montage of clips showing my negative pregnancy tests, with that one positive nestled among them. The message was simple: sometimes, the right things happen at the wrong time.

Most of the responses were overwhelmingly positive with dozens of other women sharing their stories.

And yet one reaction was anything but positive. Some friends of my boyfriend’s saw that post and took it upon themselves to assume that I was trying to trap him with a baby, and that I’d had a miscarriage. They laughed about it, making jokes to others in our group, and of course that got back to me. It’s the kind of thing you never expect — the cruelty coming from people who are supposed to be close to you. An online troll I can handle, but this felt like a new level of betrayal.

The sharp sting of it, the laughter that was aimed at me, was almost the most heartbreaking moment of all.

It’s strange how a single choice can ripple through your life, shaping not just your future, but how you share your story with the world. For me, the act of speaking out has been less about closure and more about connection, about finding solace in honesty, even when it hurts.

Time has passed. First came the due date and then a year since I had the abortion, and now I find myself excited about the future with my boyfriend. This is now just part of who I am.

But I do wish it hadn’t had to happen. I wish that I hadn’t been put in that position at all, and I still very much feel anger and disappointment that I was.

And so, when women today ask me about trusting an app with their fertility, I have one very clear answer: don’t do it.

As told to Rosie Beveridge