A person can physiologically become pregnant even while sick with the flu, but the process is complicated by the body’s acute state of illness. The flu is a systemic infection characterized by fever and widespread inflammation, which directs the body’s resources toward recovery and defense. While conception is possible if intercourse occurs during the fertile window, the illness creates an internal environment that can interfere with hormonal signals and early development. The body’s priority shifts away from reproduction, making the environment less than optimal for a seamless start to pregnancy.
How Acute Illness Affects Ovulation and Fertility
The intense systemic inflammation associated with the flu can temporarily disrupt the delicate hormonal balance required for the menstrual cycle. The body’s stress response can affect the production and release of gonadotropins, Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH), which are necessary for healthy follicular development and ovulation. Studies suggest that the severity of systemic inflammation may suppress FSH levels, potentially delaying or altering the timing of ovulation.
The biological mechanism known as “sickness behavior” involves the body prioritizing survival over non-essential functions, including reproduction. This can manifest as changes in the timing of the LH surge, which triggers the release of the egg. While the illness may delay ovulation, it does not block it entirely, meaning conception is still possible if the egg is released and fertilized. Additionally, a high fever in men can temporarily impair sperm production, with effects sometimes lasting for weeks or months.
Potential Risks of Flu Exposure During Early Development
The greatest concern about conceiving while sick with the flu involves the potential risks posed to the developing embryo, particularly due to high fever. An elevated body temperature, especially if sustained, is a form of heat exposure linked to complications during the peri-conception period and the first trimester. This risk is primarily attributed to the fever itself, not the influenza virus crossing the placenta at this early stage.
A high maternal fever during the first three months of pregnancy is associated with an increased risk of certain birth defects. Research indicates a link between maternal flu with fever and a higher chance of neural tube defects, such as spina bifida. The risk increases significantly if the mother has a fever lasting two days or longer around the time of conception.
A severe case of the flu poses dangers to the mother. Pregnant individuals are at increased risk for serious complications from influenza, including severe respiratory distress, pneumonia, and hospitalization. Being severely ill with the flu can increase the chance of later pregnancy complications, such as miscarriage and premature labor, emphasizing the importance of managing the illness aggressively.
Recommendations for Conception Planning While Sick
If you are actively trying to conceive and become sick with the flu, it is advisable to pause conception attempts until a full recovery. Allowing the body to recover ensures the reproductive system is not under the stress of acute infection and inflammation. This pause should last until the fever has subsided completely for a minimum of 48 hours without the use of fever-reducing medication.
A proactive measure for anyone planning a pregnancy is to receive the flu vaccine. The influenza vaccine is safe to receive before or during pregnancy and helps protect the mother from severe illness and the newborn after birth. The vaccine reduces the risk of contracting the virus, mitigating the dangers of fever and systemic inflammation during the early developmental period.
If conception is suspected to have occurred just before or during the illness, immediate consultation with a healthcare provider is important. The physician can offer guidance on the safe use of fever-reducing medications, such as acetaminophen, which is generally considered safe during pregnancy. This medical advice is crucial for quickly controlling any fever and minimizing the risk of heat-related complications to the developing embryo.