Antonietta D’Angelo

Lying on the couch, one of the few times I felt well enough to look at my phone, I searched "When will I feel better from HG?" Every article was different. Some said first trimester, some said second, and then I read one saying it can last until birth. I turned off my phone and lay there hopeless.

At six weeks pregnant with my first child, the nausea started. By fourteen weeks, I couldn't get off the couch. I was vomiting constantly, losing weight I couldn't afford to lose, and my partner had taken over everything—cooking, cleaning, existing in the world on my behalf. I needed IV drips to stay hydrated, saw a nutritionist and did physiotherapy just to build enough strength to get through labour.

None of this was offered to me. I found every resource myself. There was no screening, no early intervention, no one asking the right questions. I had to advocate for myself while barely able to stand.

When I think back to medical school, I remember one slide on hyperemesis during my obstetrics and gynaecology rotation. One slide. And I graduated thinking I understood pregnancy.

The moment my son was born, it stopped. Like a switch had been flipped. I felt human again instantly. But now, two years later, I'm facing a question I never expected to find so frightening: do I want to do this again?

The statistics are not in my favour. Studies suggest that somewhere between 25 and 90 per cent of women with hyperemesis will experience it again in a subsequent pregnancy. That range is wide because the research has historically been poor. Like so many illnesses specific to women, medicine didn't take this condition seriously. What I do know is that my risk is high, and my memory is vivid.

But something has changed since I was pregnant. For the first time, scientists understand what causes hyperemesis—and that understanding is finally leading somewhere.

What we now know

For decades, medicine dismissed hyperemesis as psychological. In 2023, an international research team found the answer: a hormone called GDF15.

GDF15 is produced by the placenta and acts on the brainstem to trigger nausea and vomiting. Everyone's placenta makes it. But the severity of your symptoms depends on something unexpected—not how much GDF15 your placenta produces during pregnancy, but how much you were exposed to before you conceived.

Women who naturally have low levels of GDF15 before pregnancy are hypersensitive to the rapid rise when they become pregnant. Their bodies aren't accustomed to the hormone, so the sudden surge hits them harder. Women with conditions that cause chronically high GDF15, like beta-thalaessemia, report almost no pregnancy nausea at all. Their systems are already adapted.

This also explains why some women get hyperemesis in one pregnancy but not another. It partly depends on whether the baby inherits certain genetic variants that affect GDF15 production. If the foetus produces less GDF15, the mother may be spared. If not, she's back on the couch.

For me, reading this research felt like both vindication and grief. It wasn't in my head. It was never in my head. But I went through it without anyone understanding why.

A treatment on the horizon

Understanding the cause has opened the door to something women with hyperemesis have never had: a treatment that targets the problem itself, not just the symptoms.

In February 2025, the first participant was dosed in the EMERALD trial, a Phase 2 study testing a drug called NGM120 in pregnant women with hyperemesis. The trial is running in the UK and Australia.

NGM120 is designed to block GDF15 from binding to its receptor in the brain. If GDF15 triggers nausea, this drug aims to muffle that signal. It's already been tested in over 140 non-pregnant participants for other conditions, including cancer-related nausea and weight loss, and has been well tolerated.

The trial is small and early. Participants receive a single dose alongside standard care and are followed for 7 days. We won't have results for some time, but the fact that this trial exists at all feels significant.

There's also research exploring whether women could be “desensitised” to GDF15 before pregnancy. That's further off, but it represents a shift in thinking: from managing hyperemesis after it starts to potentially preventing it altogether.

I don't know if any of this will be available in time for me. But I know it exists. And that changes the calculation, even slightly.

What I wish existed

When I imagine getting pregnant again, I don't just think about the nausea. I think about my partner, who held everything together while I couldn't move. I think about my son, who is two years old but still young enough to need me present. I think about the financial strain of weeks or months where I can't work. I think about whether my body, still recovering, could do it again.

What I need isn't a guarantee that I won't get sick. I know that's not realistic. What the system should provide is recognition that this condition matters from the start.

The first thing that would help: a way to assess risk before conceiving. The GDF15 research suggests this might one day be possible. If low pre-pregnancy levels predict hypersensitivity, a blood test could identify women at high risk. We're not there yet. But we could be.

The second: early pregnancy care that asks the right questions instead of waiting for women to report how bad things have become. Not "are you experiencing any nausea?" (a question that invites minimisation), but "are you able to eat and drink? Are you losing weight? Can you get through your day?" Screening that catches hyperemesis before it becomes a crisis, not after.

The third: a management plan made in advance. If I do get pregnant, and the nausea starts at six weeks like it did before, I should know who I'm calling, what the protocol is, and that I won't have to fight for care while I can barely stand. The plan needs to be made now, while I can think clearly, not later when I can't.

The fourth: treatment that actually works. Not ondansetron, which took the edge off but didn't stop me vomiting. Not the suggestion of steroids, which I refused (and which emerging research suggests may carry risks for the baby). Something that actually targets what's happening in my body.

Some of this exists now. Some of it is coming. Some of it may never arrive in time for me.

The decision I haven't made

I'm not pregnant. I'm not trying. I'm in the early stages of deciding whether I want to be.

My son is two. He's lovely. He was worth it. But "worth it" doesn't mean I want to go through it again without support, without treatment, without anyone asking how I'm coping until I'm already in crisis.

What's changed since my first pregnancy is knowledge. We know what causes hyperemesis now. We know it's not psychological. There's a drug in trials that might help. What hasn't changed is the system. There's still no routine screening. GPs and midwives still aren't trained to catch this early.

I don't know yet what I'll decide. But I know I'm making the decision with more information than I had before.

If you've been through hyperemesis, it wasn't in your head. And if you're facing the same question I am, you're not alone in the calculation.

For now, I'm watching the research. I'm building my team. And I'm waiting to see what becomes possible.

Antonietta is a Melbourne-based doctor and writer. She experienced hyperemesis gravidarum in her first pregnancy in 2023.