Morning Sickness: Why It Happens and What To Expect

a woman suffering from morning sickness

Morning sickness is one of the less-exciting parts of pregnancy, involving occasional or frequent episodes of nausea and vomiting during the time you carry your baby. Also known as nausea gravidarum and emesis gravidarum in technical, medical contexts, this condition affects women for different lengths of time and with a wide range of intensity, from very mild symptoms to more serious ones.

Although morning sickness can vary greatly from mother to mother and the cause isn’t definitively known, learning more about the condition will help you understand it and manage it throughout your pregnancy. Let’s look at why morning sickness happens, what to expect from it and how to address it.

Above anything else, the most important thing to remember is to speak with your OB-GYN, family doctor or other medical professional if you can’t keep food down, if your symptoms last far beyond the end of the first trimester or otherwise cause you significant discomfort or worry. They’ve worked with plenty of other moms suffering from similar symptoms, and they’ll know how to best treat you.

Woman experiencing morning sickness.Some form of morning sickness affects about 9 in 10 of all pregnant moms.

Why morning sickness happens

There’s no medical consensus for the exact reasons why so many pregnant women go through periods of morning sickness, despite how common it is. Beyond pregnancy being the common factor, there simply isn’t a definitive answer.

Even the frequency of morning sickness isn’t totally clear. The American Pregnancy Association said more than half of all pregnant women experience nausea and vomiting, but Today’s Parent put the figure between 80 and 90 percent. That’s likely because of different definitions from place to place and lack of a clear test to tell if women have morning sickness or another condition. Metro said about half of all women have nausea and vomiting, while 30 percent only suffer through nausea. While the symptoms aren’t fun by any means, they may indicate a healthy pregnancy.

“A bit of nausea is actually a good sign and may be associated with better pregnancy outcomes,” said Carolyn Lane, a family doctor at Calgary’s Low Risk Maternity Clinic, to Today’s Parent. “If the pregnancy is developing normally and all the pregnancy hormones are there, you are more likely to experience some nausea and vomiting of pregnancy.”

When does morning sickness start? The APA said this condition is most common between week 6 and week 12 of pregnancy. Thankfully this means the average length of the illness is only about one-sixth of the total time you’re pregnant. The symptoms can be shorter or longer,  and each woman’s experience can be very different. Some mothers may even experience morning sickness for one pregnancy but not another. Don’t get worried if you get nauseous or vomit during the afternoon, evening or late at night – morning sickness can strike at any time.

What to expect from morning sickness and self-care advice

Nausea and vomiting are the two clearest effects of morning sickness, and they may come at any time. That can lead to other issues caused by those conditions, including:

  • Loss of electrolytes.
  • Dehydration.
  • Weight loss.
  • Lethargy.
  • Headaches.

While the following advice won’t work perfectly for everyone, it may make your symptoms more mild and manageable:


  • Eat smaller meals throughout the day instead of a few large ones.
  • Regularly hydrate by drinking water. Consider having small amounts throughout the day instead of a few big glasses, as lots of liquid at once may trigger your symptoms.
  • Use natural nausea remedies, like ginger and peppermint, by eating small amounts or using essential oils.
  • Eat when you feel hungry, even if you ate recently or aren’t sticking to a regular schedule.
  • Get plenty of sleep and rest.
  • Eat mild foods, like soda crackers, which have less of a chance of upsetting your stomach.

It’s important to remember that if you experience prolonged morning sickness throughout the day, you may be facing hyperemesis gravidarum. The Washington Post pointed out that although rare, the severity of these symptoms mean you should speak with your doctor to further examine your experience and develop an effective treatment program.

Morning sickness is never fun, but if you approach it as something that can be managed with small lifestyle changes and discussions with your doctor, it can be easier to get through. Just remember, moderate morning sickness can be a sign your baby is progressing just as he or she should be.

Perry Robbin is a New England-born writer based in Chicago who enjoys reading, football and spending time with his niece and nephew. He’s constantly on the lookout for great New Haven and New York style pizzas. He loves his partner, Lindsey, and dog, Rocky.