Can everyone please calm down about Kim Kardashian's "pregnancy lips"?

Kim Kardashian‘s second pregnancy has been nothing short of controversial. The 34-year-old has been accused of ‘faking’ her pregnancy and using a secret surrogate, and her Instagram promotion of an anti-nausea drug attracted a stern warning letter from US health authorities. Now, the spotlight has turned to her lips.

In Kim’s latest Instagram photos her pout is visibly, well, more pouty than usual. Overnight she offered an explanation, captioning the image above: “Pregnancy lips”.

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One look at the comments underneath suggests many of her followers aren’t buying it. “What… did you mean silicone lips?” one said. “I didn’t know pregnancy caused lip fillers,” wrote another.

Considering the Kardashian-Jenner family’s history of lip filler speculation (which in Kylie’s case turned out to be accurate), and the fact Instagram can get snarky pretty quickly, this response isn’t entirely surprising. However, it seems Kim wins this round — sorry, keyboard warriors.

“It’s absolutely true that [pregnancy] can cause swelling of the lips. It is a real phenomenon,” says Dr Jodie Silleri, General Practitioner and Cosmetic Physician with Melbourne’s enRich Dermatology and Cosmetic Surgery Center.

It all comes down to fluid retention; pregnancy causes a woman’s hormonal balance to change, which can result in fluid shifts particularly around the second and third trimester. Dr Silleri says around a quarter of weight gain during pregnancy is tied to fluid retention.

“More commonly we retain fluid in the legs and the ankles and feet, but we can also retain it in the hands and the face. As a doctor, I see women who are pregnant with swollen lips,” Dr Silleri explains. (Post continues after gallery)

This additional fluid serves an important purpose — it softens the body to enable it to expand as the baby develops and helps to prepare a woman’s pelvic joints and tissue for delivery.

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Certain lifestyle factors cause some women to experience more swelling than others. Hot temperatures, standing up for long periods of time, or eating a diet low in potassium or high in salt and caffeine can all contribute. (Post continues after video.)

Interestingly, Dr Silleri has observed that in women who have previously had lip injections, their lips tend to swell “proportionally more” during pregnancy than other women’s.

“That’s just my anecdotal observations … I don’t know exactly what the mechanism behind that is, it could be some remaining hyaluronic acid that’s drawing the water to it,” she says.

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While there’s not much you can do to combat pregnancy-induced fluid retention, Dr Silleri says in general it’s good to avoid standing for long periods or going outside for too long in hot weather; comfortable shoes and clothing and cold compresses can also help. If you want to reduce the puffiness in your face, you might want to look at your sleeping arrangement.

“The more upright you are, the more chance you’re going to have a swollen face; when you lie flat, you get 20 per cent more bloodflow to the head. So sleeping on a couple of pillows may help,” Dr Silleri adds.

Although it's normal to experience "slight swelling" during pregnancy, Dr Silleri says sudden swelling in the hands and face could be a sign of pre-eclampsia, a more serious pregnancy condition. If this is the case, the swelling will be accompanied by additional symptoms like abdominal pain, dizziness and nausea, and it's important to seek medical attention.

Incidentally, Kim Kardashian battled pre-eclampsia during her first pregnancy; it was so severe her doctors decided to induce her labour five weeks early.

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As for the commenters discussing whether Kim has been having lip fillers throughout her pregnancy, Dr Silleri says that's highly unlikely as doctors and nurses will refuse to use dermal fillers on women who are pregnant or planning to be.

Did you experience fuller lips during pregnancy?