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Kate Middleton's Hyperemesis Gravidarum: What Is It?

It's real, but there is no cure for it because nobody knows what exactly causes it.

Image: Britain's Catherine, Duchess of Cambridge arrives for a visit to the White Garden ::  /
The Duchess of Cambridge is pregnant with her third child, and experiencing her third bout of hyperemesis gravidarum. Hannah Mckay / Reuters file
The Duchess of Cambridge is pregnant with her third child, and experiencing her third bout of hyperemesis gravidarum. Hannah Mckay / Reuters file

The news that Kate Middleton is expecting her third child may have the public squealing with delight, but many of us are also a bit concerned for her and baby’s wellbeing. As with her two prior pregnancies, the Duchess of Cambridge has Hyperemesis Gravidarum (HG), a condition that is characterized by severe nausea, vomiting, weight loss and dehydration.

Between 0.5 percent and three percent of pregnant women suffer from HG, says Sara Twogood, assistant professor of clinical obstetrics and gynecology at Keck Medicine of USC.

What does that percentage looks like in terms of actual cases? Dr. Marlena Schoenberg Fejzo, associate faculty researcher at UCLA and USC says “a very rough estimate would be about 100,000 women per year suffer from HG in the US annually.”

Fejzo adds that HG accounts for over 167,000 ER visits per year.

Hyperemesis Gravidarum: A Condition With ‘No Strict Definition’

That this condition doesn’t have a precise number of diagnoses to reference it is part of a bigger problem: HG runs on a spectrum, with no distinct definition.

If you have a sister who has hyperemesis gravidarum you have a 17-fold increase risk of having it.

If you have a sister who has hyperemesis gravidarum you have a 17-fold increase risk of having it.

"Different clinicians use different criteria to meet the definition of [HG],” says Twogood. “There’s really no strict definition."

Some women may have HG and not know it, which makes sense given that two of its key symptoms (nausea and vomiting) are often seen in normal pregnancies. Women may not know that what they’re experiencing isn’t just what to expect when they’re expecting.

“Twenty-five percent of pregnant women will have nausea and 50 percent of pregnant women will experience nausea and vomiting,” Twogood says of normal pregnancies, adding that even clinicians can overlook HG.

Jenn Morson Frederick, a 41-year-old writer in Washington, D.C, currently pregnant with her fifth child (and, ugh, experiencing HG for the fifth time), initially brushed off HG as being par for the course.

"With my first, I was about 5.5 weeks pregnant [when the HG set in]. I had lunch at my in-laws, promptly threw up and figured it was morning sickness,” said Morson Frederick. “Then I couldn't keep anything down: no crackers, no water, no ginger ale — nothing. I ended up going to the ER.”

She went three more times before meeting with an OB/GYN who properly diagnosed her.

The Symptoms of Hyperemesis Gravidarum — And The Misconceptions

A clear definition of HG may be lacking, and cases could slip under the medical radar, but both Twogood and Fejzo underscore that HG has clear symptoms including severe nausea, persistent vomiting, loss of appetite and weight loss.

“If you lose five percent of your pre-pregnancy body weight weight or more it is considered HG,” said Fejzo. “This is usually accompanied with an electrolyte imbalance and dehydration.”

There is no cure for hyperemesis gravidarum because nobody knows what exactly causes it.

“I am a geneticist by training and this is what I've been working on,” says Fejzo. “We know it runs in families, and that if you have a sister who has had it you have a 17-fold increase risk of having it.”

Also, if you’ve had it before, you will likely experience it in future pregnancies.

Why aren’t there more answers? For one thing, HG wasn’t taken seriously as a medical problem until recently. It was either shrugged off as a bad case of morning sickness (evidently, it still can be), or was dismissed as a purely psychological problem.

“There have been theories that this is something psychological [stemming from] a woman’s inability to cope with the stress of being pregnant,” says Twogood. “This is a dangerous dismissal.”

Indeed it is, as HG can actually be fatal (tragic trivia: it has been speculated that Jane Eyre author Charlotte Bronte died from HG-related complications).

“Deaths from HG are hard to track because usually the cause of death is something secondary to [but linked to] HG, such as a heart attack, stroke or Wernicke's encephalopathy, which is caused by a vitamin B1 deficiency, so their death reports don't necessarily list HG,” says Fejzo.

While there is no cure for HG, there are ways of treating it. You absolutely have to consult a doctor, and what works for one sufferer may not work for another, but medications such as Dicleges, Phernegan, Ondansetron, and Reglan are among those that Twogood and Fejzo say are used to manage HG symptoms.

With All the TMI That Comes With Hyperemesis Gravidarum, Support Groups Help

Even with treatment, HG can completely wipe you out and alienate you from your family and routine, making it not only a physical hardship, but an emotional one, too. Fejzo notes that those with HG often have to sleep in separate rooms from their partners (the sheer smell of another person can be gag-worthy), and just being in the kitchen (let alone cooking) can be unbearable, also because of the smells.

After going through HG with my first, I never imagined I'd have anymore babies — it scared me so much.

After going through HG with my first, I never imagined I'd have anymore babies — it scared me so much.

“To this day, I can’t stand the faintest trace of ginger, as it reminds me of the tea, ale, gum, drops, candy, (even soap) that well-meaning friends offered me,” says Shara Lessley, a writer and mother of two living in Oxford, England who was diagnosed with HG during her second pregnancy a few years ago. “If my husband rolled over during his sleep or even adjusted a blanket, I felt like a Dory in plunging waves. A fire alarm went off [and it sounded] so loud I rushed from the building and into the street to be sick.”

TMI? That’s one of the joys of HG.

“It's very difficult to discuss [HG] without being graphic and, frankly, over-sharing,” adds Lessley.

Fortunately, there are no shortage of women who will gladly listen to you and chime in with their own stories in various support groups — an optional part of treatment that both Twogood and Fejzo stress is crucial.

Tasha Crabb, a 29-year-old mother of two (with a third on the way, and alas, a third case of HG) launched the Hyperemesis Gravidarum Support Group on Facebook two years ago. The bonds she has built within the group have helped her through her subsequent pregnancies.

“After going through HG with my first, I never imagined I'd have anymore babies — it scared me so much,” says Crabb. “[But] when I started seeing and hearing about moms with HG at their wit’s end, I knew I had to try and do something, even if it meant just trying to help one mom out there; I wanted to get the word out on HG and let moms know they are not alone.”

Crabb says the group is always open to new women with HG, and can be regarded as a “safe haven where HG moms can vent without judgment, and get advice on how to try and manage their HG.”

The more support the better, which is partly why UCLA has partnered with the HER Foundation (a network of HG survivors and an HG information site) to develop a new app called HG Care, which, still in beta testing (and seeking the input of HG sufferers), could become a techy tool for women with HG, enabling them to track their symptoms, access info, get alerts, make charts, and find support.

“Everybody needs support,” says Fenzo. “I’ve had grandmothers of women with HG reach out to me for support.”

HG isn’t a walk in the park for anybody, but it’s also something that most women can manage with the right treatment and a solid support system. And while it may feel like forever, it does end.

“It sucks, but there's an expiration date,” says Morson Frederick. “You can do this. Ask for help, advocate for yourself to your doctor and don’t be afraid to get a different doctor if yours isn’t supportive or knowledgeable.”

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