That said, some research has found that pregnant people who experience morning sickness have a statistically lower risk of miscarriage, but most people in both groups will have healthy pregnancies. Another study found that in people who had experienced a prior miscarriage, the symptoms of morning sickness were associated with reduced risk for pregnancy loss in subsequent pregnancies. However, that doesn’t mean it’s a cause for concern if you do not have morning sickness, especially if there are no signs that anything is wrong. Here’s what you need to know about morning sickness, pregnancy, and miscarriage risk, as well as when you should talk to your healthcare provider about your symptoms.
How Common Is Morning Sickness?
As many as 80% of people experience nausea (with or without vomiting) at some point in their pregnancy. That means as many as 20% have no morning sickness, and many of these people go on to have a healthy, uncomplicated pregnancy. Morning sickness usually resolves on its own in a few months. However, it is still normal for morning sickness to occur at any point during pregnancy. While the symptoms can be uncomfortable and disruptive, they generally do not pose a risk to a pregnant person or the fetus. Of the people who do experience symptoms of morning sickness, most report that the symptoms resolve by week 22 of pregnancy. However, about 10% of pregnant people have morning sickness that lasts up until they give birth.
Hyperemesis Gravidarum
Severe morning sickness is known as hyperemesis gravidarum. It occurs in only about 3% of pregnancies, but it can be serious. There’s no single reason why some people get the condition and others do not, but genetics are thought to play a role in an individual’s risk. A person with hyperemesis gravidarum experiences severe vomiting on a daily basis, which leads to dehydration and weight loss. While a little weight loss during the first trimester can be normal, losing 5% of your body weight or more is not.
Lack of Morning Sickness
About one-third of pregnant people in Western society do not report any symptoms associated with morning sickness. In several non-Western societies, morning sickness is less common—in some places, morning sickness has never been documented. In at least seven traditional societies, there is a known lack of morning sickness in pregnant people. While the research is not definitive, it’s been theorized that the plant-based, whole-food diets these cultures follow might contribute to their lower rates of morning sickness. Fluctuations in pregnancy symptoms are normal and there can be a wide variation between pregnant people. While it can be hard not to worry and you do want to pay attention to how you are feeling, try not to overanalyze your pregnancy symptoms.
Causes
Several factors are believed to contribute to morning sickness, including the hormonal changes of pregnancy and genetics. The possible causes of morning sickness symptoms that have been the most well-studied are biological factors such as levels of pregnancy-specific hormones (beta hCG, estrogen, and progesterone) and genetic influences. During the first trimester of pregnancy (when morning sickness symptoms tend to be worst), several major hormonal shifts take place. Pregnant people who have higher levels of hCG (such as those carrying multiples or a female fetus) often have worse symptoms of morning sickness. For example, a study in Japan in 2018 found that pregnant people who were carrying a female fetus had more severe morning sickness than people carrying a male fetus. Morning sickness was also noted to be worse in people who were carrying multiples—especially if one or more fetuses were female. However, the link is not definitive, and several other studies have found no association between the severity and duration of morning sickness symptoms and hormone levels. Your genetics likely also plays a role in whether you’ll experience morning sickness. Research has shown that the tendency for nausea and vomiting during pregnancy seems to run in families.
Treatment
As mentioned previously, your diet might be a protective factor. If you are pregnant and do not have any symptoms of morning sickness, consider whether what you eat could partially explain your lack of symptoms. For example, it’s been suggested that nausea and vomiting in early pregnancy could be an evolutionary “trick” to ensure a pregnant person is paying enough attention to their diet and nutrition. Another theory is that vomiting, in particular, might be a safeguard against toxic substances that could harm a pregnant person or fetus. If you have morning sickness, you might find that making some changes to your diet can help ease or prevent symptoms. Dietary changes you might want to try include:
Drinking plenty of fluidsEating five or six small meals a day rather than three big mealsFollowing the BRAT (bananas, rice, applesauce, and toast) diet and bland foods (broth or Saltine crackers) when you feel sickHaving a small snack when you first wake up and before you go to bedTrying ginger candy, capsules, or tea to reduce nauseaTalking to your provider about taking a vitamin B6 supplementUsing motion sickness wristbands or acupressure points
Prescription Medications
If your morning sickness is severe or gets worse and you are losing weight, your provider might give you a prescription anti-nausea medication such as Zofran (ondansetron) or Unisom (doxylamine succinate). They might also recommend that you try a newer anti-nausea drug (Diclegis and Bonjesta) that is combined with vitamin B6 and doxylamine succinate.
When to Call Your Provider
Morning sickness is more common than not, but if you don’t develop the symptoms, it does not necessarily mean you need to be concerned. It’s not a definitive sign that something is wrong with your pregnancy.
Severe Symptoms
A bigger concern related to morning sickness is at the other end of the spectrum—severe symptoms. While it’s not common, hyperemesis gravidarum can make you very sick and requires treatment and careful monitoring. If your symptoms are not resolved with remedies, do not seem to be improving or are getting worse as your pregnancy progresses, and/or you’re losing weight, it’s important that you talk to your provider.
Signs of Miscarriage
Not having morning sickness is not necessarily a sign of miscarriage. However, there are signs and symptoms that could indicate pregnancy loss is impending or has already happened. While you do not want to become overly concerned about a possible miscarriage, it’s important that you know the signs or symptoms. Miscarriage signs and symptoms can include:
Vaginal bleeding Pelvic pain or lower back pain (can be constant or might come and go) Pregnancy symptoms that suddenly disappear (this could include morning sickness, fatigue, and breast tenderness that rapidly gets better) Other possible symptoms that are less common include increased vaginal discharge, leaking amniotic fluid, or passage of tissue
A Word From Verywell
Symptoms of nausea and vomiting are common in early pregnancy. Even though it’s called “morning sickness” these symptoms can occur at any time of day. They can also appear at other points in pregnancy—not just at the very beginning. Some people do not experience any symptoms of morning sickness during their pregnancy. While some research has theorized that morning sickness has a protective effect against miscarriage, this does not mean that you should be worried if you don’t have symptoms. Many people do not experience morning sickness and have a completely healthy, uncomplicated pregnancy. You don’t want to become overly preoccupied with pregnancy symptoms, including those of morning sickness. That said, it’s important to pay attention to how you are feeling. While morning sickness symptoms might not necessarily correspond to your risk of a miscarriage, they can still present other health problems. Most of the time, morning sickness is uncomfortable and disruptive, but not serious and gets better with time (especially with dietary changes and remedies). However, if you develop severe morning sickness (hyperemesis gravidarum), it’s important that you talk to your provider. You might need more treatment, such as prescription medication, to manage your symptoms and prevent weight loss.
