Pregnancy involves distinct physiological changes that can alter the body’s response to temperature and pathogens. While some expecting individuals feel warmer due to the internal work of growing a baby, others experience unexpected and persistent chills. These temperature fluctuations and shifts in immune response result from complex adaptations the body undergoes to support the developing fetus.
Physiological Reasons for Feeling Colder
The sensation of feeling cold during pregnancy often stems from changes in the body’s thermoregulation system. Hormonal shifts, particularly the significant increase in progesterone, influence the body’s internal thermostat, sometimes leading to a lower core temperature set point. This hormonal effect can cause fluctuations that make a person feel chilly even in a mild environment.
Pregnancy also necessitates a substantial increase in basal metabolic rate (BMR) as the body works harder to sustain the pregnancy, which surprisingly can contribute to the cold sensation. This elevated metabolism generates heat, but the body’s subsequent attempts to regulate and dissipate this extra heat can lead to a rapid cooling effect. If the body is momentarily less active, the decrease in internal heat production can result in a sudden feeling of coldness.
The substantial increase in blood volume, often 40% to 50% more than pre-pregnancy levels, is primarily directed toward the uterus and essential organs. This redistribution often results in decreased circulation to the extremities, such as the hands and feet. Cooler hands and feet are a frequent complaint, contributing to an overall feeling of coldness despite a normal core body temperature.
Furthermore, iron-deficiency anemia is a common condition during pregnancy due to the increased blood volume and demands of the fetus. Anemia reduces the oxygen-carrying capacity of the blood, which can impair circulation and tissue oxygenation. This diminished efficiency in oxygen transport can leave many individuals with a chronic feeling of coldness, a symptom directly linked to the circulatory challenges of the condition.
How Pregnancy Affects Susceptibility to Illness
The body’s immune system undergoes a carefully controlled adaptation to ensure the fetus, which is genetically semi-foreign, is not rejected. This necessary tolerance is achieved, in part, by shifting the immune response away from a strong, cell-mediated defense known as the T-helper 1 (Th1) response. The shift favors the T-helper 2 (Th2) response, which is more associated with antibody production and plays a larger role in maintaining the pregnancy.
This suppression of the Th1 pathway, which is normally responsible for fighting off many common viral and bacterial infections, can increase susceptibility to illness. Infections like the common cold or influenza may be contracted more easily because the initial line of defense is temporarily downregulated. The immune system is not compromised entirely, but its focus is strategically altered.
In addition to a potential increase in the frequency of catching illnesses, the shift in immune function may also prolong the duration or severity of symptoms. The symptoms of a cold, such as congestion or a cough, can feel more intense or take longer to resolve due to the body’s adapted, less aggressive inflammatory response. This altered response is a trade-off: maintaining the pregnancy at the expense of a fully robust, non-pregnant level of defense against pathogens.
Safe Remedies for Cold Symptoms and Discomfort
Managing cold sensations and mild illness symptoms during pregnancy requires prioritizing non-pharmaceutical methods for comfort and safety.
Non-Pharmaceutical Comfort Measures
- Wear layers of clothing and ensure adequate indoor warmth to manage temperature fluctuations.
- Gargle with warm salt water for a sore throat to provide soothing relief.
- Stay properly hydrated with fluids (warm tea, honey, or broth) to aid temperature regulation and thin mucus secretions.
- Use a cool-mist humidifier while sleeping to reduce nasal congestion and soothe irritated airways.
- Apply nasal saline sprays to moisturize nasal passages and loosen thick mucus without systemic medication exposure.
When symptoms require medication, acetaminophen is generally considered a preferred option for managing fever, headaches, and body aches throughout all trimesters. Certain single-ingredient cough suppressants, like dextromethorphan, and expectorants, such as guaifenesin, may also be used in consultation with a healthcare provider. Avoid multi-symptom cold remedies, as they often contain ingredients that may not be safe, and do not take nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, particularly after 20 weeks of gestation.
When to Contact a Healthcare Provider
While most cold symptoms during pregnancy are manageable, certain signs warrant immediate medical consultation to rule out more serious complications.
Warning Signs Requiring Medical Attention
- A persistent or high fever (100.5°F or greater) that does not decrease after taking acetaminophen. Fever during pregnancy carries risks and its underlying cause needs prompt investigation.
- Difficulty breathing, shortness of breath, or a persistent, deep cough that produces discolored mucus. These symptoms could indicate a secondary bacterial infection, such as pneumonia or bronchitis.
- Symptoms that last longer than ten days or that initially improve but then return with greater severity.
- Signs of severe dehydration, such as significantly reduced urination or extreme dizziness.
- A sudden or sustained decrease in the frequency of fetal movements.
A healthcare provider can offer personalized guidance on safe treatment options based on the stage of pregnancy and individual medical history.