The following information is to be used as a guide to and at the discretion of the end-user and should not replace a doctor’s opinion.
OVERVIEW
Morning sickness — medically referred to as nausea and vomiting of pregnancy (NVP) — is one of the most common symptoms experienced during early pregnancy worldwide. While often uncomfortable and inconvenient, it is usually a normal part of early gestation. However, some women experience severe symptoms that require medical care.
Despite the commonly used name, nausea and vomiting as symptoms of pregnancy can occur any time of the day or night, not just in the morning. It typically begins around 6 weeks gestation, peaks between 9–16 weeks, and usually improves by about 12–14 weeks of pregnancy.
It is thought to be a natural response to pregnancy-related hormonal changes, such as increased levels of human chorionic gonadotropin (hCG) and oestrogen. The exact biological cause is not fully understood, but hormones that support early pregnancy are implicated in triggering nausea pathways in the brain and slowing digestive motility (the rate at which the stomach empties).
WHAT CAUSES MORNING SICKNESS?
Morning sickness arises from a combination of physiological and hormonal changes:
- Hormonal fluctuations
Rising levels of pregnancy hormones, especially hCG, oestrogen, and progesterone, are strongly associated with nausea and vomiting. These hormones may affect the brain’s “vomiting centre” and gastrointestinal motility.
- Gastrointestinal sensitivity
Slower digestion due to progesterone can cause food to remain longer in the stomach, increasing feelings of nausea and vomiting.
- Central nervous system changes
Some research suggests that specific pregnancy-associated hormones like GDF15 may influence centres in the brain responsible for nausea, particularly in severe presentations such as HG.
The exact interplay between these factors remains an area of active research.
HOW COMMON IS MORNING SICKNESS?
On average, 70–80 % of pregnant women experience some degree of nausea and vomiting during pregnancy:
- Global clinical studies estimate that up to 85 % of women experience these symptoms.
- Most cases are mild to moderate and resolve by the end of the first trimester.
Less that 2% of pregnant women experience severe morning sickness (hyperemesis gravidarum).
SEVERE MORNING SICKNESS: HYPEREMESIS GRAVIDARUM
A small proportion of women experience hyperemesis gravidarum (HG) — a severe, debilitating form of morning sickness characterised by persistent vomiting, weight loss, dehydration, and electrolyte imbalance.
HG affects approximately 0.3 – 2 % of all pregnancies worldwide. It sometimes begins as early as 4–6 weeks, peaks around 8–12 weeks, and for most women improves by around 20 weeks, though it can persist longer in some cases.
HG can lead to significant complications such as dehydration, nutritional deficiencies, and metabolic disturbance if not treated appropriately.
Risk factors:
- Previous history of hyperemesis
- First pregnancy
- Young age
- Obesity
- Family history
- Iron Supplements
- History of motion sickness and/or migraines
When to contact your healthcare provider
Morning sickness is usually a normal part of early pregnancy, but seek medical help if you experience:
- Inability to keep fluids down for more than 24 hours
- Signs of dehydration, such as dark urine, dizziness, or fainting
- Rapid or excessive weight loss (over 5 % of pre-pregnancy body weight)
- Inability to eat or drink at all
- Signs of complications like severe abdominal pain or confusion
These may indicate hyperemesis gravidarum or other medical conditions needing urgent attention.
MANAGING MORNING SICKNESS
HOME REMEDIES
MEDICAL AND PHARMALOGICAL TREATMENTS
If lifestyle adjustments aren’t enough, healthcare providers may recommend medications that are considered relatively safe in pregnancy when used appropriately:
- Vitamin B6 (pyridoxine) supplements — as an initial therapeutic option.
- Antiemetic drugs such as metoclopramide, ondansetron, or promethazine, usually under clinical supervision.
In cases of hyperemesis gravidarum, management may include:
- Intravenous (IV) fluids and electrolytes to treat dehydration.
- Nutritional support and micronutrient supplementation (e.g., thiamine) due to intake deficits.
- Hospitalisation for persistent or severe symptoms not responding to outpatient therapy.
Treatment plans are tailored to symptom severity and individual health circumstances.
CULTURAL AND REGIONAL REMEDIES
A study on South African, urban, and rural women found that severe nausea ranges from 3.8% in rural black women to 19.8% in white women. Pica, the craving for non-food items like clay or sand, was more frequently reported among rural and urban black women.
Many of these women turn to traditional medicines to manage morning sickness — for example, some may use herbal remedies whose safety and effectiveness are not scientifically established. Before taking any local remedy, it is best to speak with your healthcare provider about safe, evidence-based management strategies.
FURTHER READING
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