An acute fever during pregnancy can signify a serious issue for both you and your developing baby. It's crucial to act promptly when a fever or chills develop by reaching out to your healthcare provider. An acute fever is defined as a sudden body temperature increase beyond the normal 98.6 degrees Fahrenheit. ### Understanding Acute Fever During Pregnancy #### First Trimester Concerns If your body temperature rises above 101 degrees Fahrenheit during the [first trimester of pregnancy](/checklists/first-trimester-checklist), this could indicate an infection that might impact your unborn baby. Symptoms such as fever, sore throat, fatigue, and swollen glands may suggest [cytomegalovirus (CMV)](/infections/cytomegalovirus-cmv-infection), which has the potential to cause hearing loss, vision issues, and other disabilities in your baby. #### Influenza and Pregnancy Pregnancy can increase your vulnerability to the influenza virus. [Influenza](/pregnancy-symptoms/cold-and-flu-symptoms-pregnancy) can lead to a fever and is more likely to cause severe illness during pregnancy compared to non-pregnant women. Notably, contracting the flu during pregnancy can lead to complications such as [premature labor](/prematurity/preterm-labor) and [premature delivery](/complications/premature-birth). #### Second Trimester Considerations In the [second trimester](/checklists/second-trimester-checklist), a fever can hint at a possible [urinary tract infection (UTI)](/infections/urinary-tract-infection-during-pregnancy). Symptoms often include fever, shaking chills, backache, and a burning sensation during urination. Untreated UTIs can spread to your kidneys, significantly increasing the risk of [preterm labor](/prematurity/preterm-labor). #### Third Trimester Dangers [Listeriosis](/food-and-nutrition/unpasteurized-milk-and-listeria) is another concern, particularly in the [third trimester](/checklists/third-trimester-checklist). This bacterial infection, caused by consuming contaminated foods, manifests as fever, muscle aches, chills, and sometimes nausea or diarrhea. Listeriosis can lead to early delivery or even [miscarriage](/miscarriage). ### Taking Swift Action Fevers in the first and second trimesters hold the potential to impact your baby’s development, while those occurring in the third trimester can complicate labor and delivery. If your fever spikes suddenly or your temperature hits 101 degrees Fahrenheit, it’s essential to contact your physician without delay. By taking immediate action, you are significantly enhancing your chances of a healthy pregnancy and delivery. For more insights on high-risk pregnancy considerations, explore the resources available through the [U.S. Department of Health and Human Services](http://www.womenshealth.gov/pregnancy/), or delve into curated information provided by reputable health agencies. [pHigh-Risk Pregnancy >](/complications/high-risk-pregnancy-maternal) #### Source: - John W. Schmitt, MD. *Office on Women's Health.* [U.S. Department of Health and Human Services](http://www.womenshealth.gov/pregnancy/). 27 Sept. 2010. Updated 10 Sept. 2013. - ["Chlamydia - CDC Fact Sheet"](http://www.cdc.gov/std/chlamydia/stdfact-chlamydia.htm) *Centers for Disease Control and Prevention.* 11 Feb. 2013. Updated 10 Sept. 2013.