Are fever and chills early signs of pregnancy?

Having body temperature above the normal limit of 98.6° F (37° C) is considered a fever [1]. Fever and chills are not counted among the normal signs of pregnancy as they might indicate several underlying conditions [2]. However, there are plenty of ways to treat a fever while carrying before it can harm you or your baby.

Symptoms of fever in pregnancy

The common symptoms are the same as you are likely to get with fever even when you are not pregnant:

  • High temperatures
  • Chills
  • Headache [3]
  • Sweating
  • Fatigue
  • sore throat
  • Muscle pain [1]
  • Dehydration

Causes of fever and chills in pregnancy

The rising pregnancy hormones change your immune responses to help the fetus grow properly [4]. This makes you more susceptible to common viral conditions like fever, cold and cough [5], often leading to low grade fever along with flu-like symptoms. On the other hand, although the hormones are more likely to make one feel warm and sweaty, some women may get the opposite effects of feeling cold and chilled, commonly early in the first trimester [6].

However, there are many infections and other health conditions that might lead to raised body temperature along with the other symptoms. These include influenza, common cold and a stomach bug [2]. Thyroid problems diagnosed in pregnancy may also cause the unexplained chills while other more serious causes include various infections [6].

Differential diagnosis for fever during pregnancy

Blood and urine tests may be performed [7] to determine the exact causes of your fever as well as to establish the differential diagnosis [8]:

  • Cholecystitis
  • Appendicitis
  • Urinary tract infections
  • Q-fever
  • Amebiasis
  • Hepatitis A/B
  • Typhoid
  • Rubella
  • Abscesses (hepatic, pelvic, cerebral)
  • Rheumatic fever
  • Scarlet fever

How to treat a fever while pregnant?

It is always advisable to consult your doctor before trying any natural remedies or medical treatments to properly understand the causes behind the raised temperatures and chills. The treatment varies depending on the condition and its severity. Low grade fevers are usually not a serious cause of concern as they often go away on their own [9].

Tips and home remedies to manage a low grade fever

  • Drinking lots of fluid to keep your body well-hydrated [5]
  • Taking lots of rest, staying in bed as long as you want to; but try to stay cool (unless you have the chills) as getting overheated might harm the fetus [10]
  • Pressing a cold compress on your forehead to lower the temperature [3]

Safe medication

Tylenol (acetaminophen) has been considered a safe fever medicine for pregnant women for a long time [11]. However, a recent study suggests an association between the use of Tylenol and an increased risk of ADHD in the child [12]. NSAIDs such as Advil (ibuprofen) are not recommended during this time as they might be harmful for the fetal cardiovascular system [3]. It is best to talk to your health care provider before using any medications for fever.

Dietary tips for getting rid of a fever

  • Eating plenty of fruits and vegetables (especially those rich in vitamin C like citrus fruits, cantaloupe, honeydew etc.) as they are useful for treating as well as preventing cold and fever [5]
  • Including low fat dairy products and other calcium rich foods to your diet
  • Having hot chicken soup with lots of well-cooked vegetables
  • Drinking decaffeinated tea [5]

Does a fever in pregnancy harm your baby?

Running a fever over an extended period of time in the first and early second trimesters can hamper the growth of your baby, leading to various birth defects including central nervous system or neural tube defects [13], cataracts, heart anomalies, micrencephaly (abnormally small braincase) and abdominal wall defects. Extremely high temperature within the first month of pregnancy is sometimes associated with higher chances of miscarriage [9]. According to some studies, a long-running fever any time in pregnancy can increase the risks of autism and developmental delay [14]. However, having a mild fever in the third trimester does not usually affect the baby unless it is caused by some serious condition [13].

When to call the doctor?

  • Having a fever that lasts longer than 24-36 hours
  • Fever over 100° F at any stage of pregnancy [15]
  • Fever accompanied by bleeding and period-like cramps (might indicate serious complications relating the fetus and placenta) [16]
  • Fever and chills along with rashes, severe nausea [3], vomiting, dizziness, abdominal cramps, joint pain, back pain and contractions (might indicate infectious conditions like a kidney infection) [6]
  • Elevated temperatures with severe vomiting, nausea and diarrhea (puts you in danger of dehydration)
  • Having a fever while your waters break [7]
  • Fever with severe lower abdominal pain, bleeding, weakness and vomiting (might indicate an ectopic pregnancy) [17]
  • Having a fever along with migraine [18]
  • The usual fever symptoms along with jaundice (indicates a yellow fever)
  • Severe chills with or without fever (might indicate conditions like anemia and low blood pressure)

Fever ICD-9 and ICD-10 codes

The ICD-9 code used for indicating fever is 780.6 [19], while its ICD-10 code is R50 [20].[ref]