Explaining the Cruel Injustice of Morning Sickness

Blame it on your hormones

woman suffering from morning sickness

Your pregnancy test came back positive. Minutes later (it seemed), you were retching over the toilet bowl. And you haven’t stopped for 12 lousy weeks. Meanwhile, your pregnant coworker has never felt better. What gives?


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Morning sickness can be brutal. But you know what they say: Knowledge is power. So to help you cope, here’s the 411 on your pregnancy tummy troubles from Ob/Gyn Julian Peskin, MD.

What causes morning sickness? Hormones!

“Increasing levels of the progesterone hormone triggers smooth muscle like your stomach and intestines to relax,” says Dr. Peskin.

What that means for you:

  • Digestive processes slow down causing food to hang out longer in your stomach (and that seasick feeling).
  • The esophageal sphincter — a valve between the stomach and esophagus — relaxes.
  • The now-lazy valve allows your stomach’s contents to move back up into the esophagus.
  • Heartburn happens, which can make nausea worse.
  • This nonstop nausea coaster can make you feel like puking.

“We also know estrogen can cause nausea because when women start birth-control pills, they often experience a bout of nausea,” says Dr. Peskin. “During pregnancy, estrogen is on the rise so it’s not surprising that nausea would rise with it.”

So why is your pregnancy nausea worse than your friend’s?

Dr. Peskin doesn’t have a definitive answer for this million-dollar question. But he CAN tell you that people with severe morning sickness — hyperemesis gravidarum — have higher levels of the hCG (human chorionic gonadotropin) hormone. Your body produces hCG when you become pregnant.


It seems likely, then, that the higher your hormone levels are, the worse your morning sickness is. But do higher levels of hormones mean a healthier pregnancy?

“Not necessarily,” says Dr. Peskin. “One woman can have absolutely no morning sickness, and one can have it horribly … but they both have healthy pregnancies.”

But look on the bright side. While your level of morning sickness may not correlate to pregnancy health, it can provide reassurance that your pregnancy is still on track. Usually morning sickness will start subtly at week 5 or 6, then peak around week 9, before gradually going away by 12 to 14 weeks.

“Pregnancy nausea that is here one day and gone the next may mean there is a hormonal change that could jeopardize the pregnancy,” says Dr. Peskin. “If you wake up one day and realize your morning sickness has disappeared overnight, make a call to your doctor so they can check things out.”

Vomiting: the dark side of pregnancy sickness

Dr. Peskin says another question he often gets is why some women yak with morning sickness and others don’t.

“I suspect that women who are prone to vomiting outside of pregnancy have a reflex that allows them to vomit more easily,” says Dr. Peskin. “Some women find it easier to throw up when they don’t feel well in general, whereas others just can’t.”

One thing is for sure: Vomiting can lead to dehydration, and that can be dangerous.

“Women who haven’t kept things down for 24 hours or who have any signs of dehydration should seek care,” says Dr. Peskin.

Typical signs of dehydration include:

  • Decreased urination.
  • Dry mouth.
  • Dry or itchy skin.
  • Dizziness or weakness.

Morning sickness? Forget about it — I feel lousy all day

The term morning sickness is a misnomer. For 80% of women, nausea doesn’t occur just in the morning. But in most cases, women will get a reprieve from nausea while they sleep.

“Most people can tailor their meals to when they have nausea,” says Dr. Peskin. “If you’re only sick at certain times of day, then eat meals and get nutrients when you’re feeling less sick.”

Even if you have marathon morning sickness, you can often find ways to eat small, frequent meals to avoid the stomach overload that may increase nausea. Several tummy tamers also offer relief.

“And if your stomach feels more settled at night, but the heartburn ramps up, I’d suggest getting a wedge pillow to help you sleep more upright,” says Dr. Peskin. “That way you’re using gravity to keep food from backing up into your esophagus.”


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