Several pregnancy symptoms do indeed mimic flu symptoms, especially early in the first trimester. In fact, your first signs of pregnancy may be feelings of the never-ending flu. Flu symptoms should not last more than a couple of weeks. If you have these symptoms and there is a chance you could be pregnant, consider taking a pregnancy test to be sure.
Rise in Temperature
With pregnancy and sometimes the flu comes a rise in temperature. For those charting their waking basal temperature, you will see this rise following ovulation. A high waking basal temperature that lasts 18 days indicates a pregnancy, according to Toni Weschler’s book “Taking Charge of Your Fertility.” The difference is just how high the temperature goes. Your temperature during pregnancy will be higher than normal but should not go above 100 degrees F. Fevers associated with the flu are much higher than the higher-than-normal temperatures associated with pregnancy.
From mild nausea to severe vomiting, this symptom could indicate the flu or pregnancy. According to the Centers for Disease Control and Prevention, upset stomach and vomiting are not a common flu symptom for adults, although it can occur in some individuals. If you do not normally have stomach upset with the flu, or these symptoms are not subsiding, call your doctor. You may be pregnant or have a more serious flu virus that needs treatment.
Hormonal changes, metabolism changes and the body’s efforts to grow a baby cause a general feeling of fatigue in early pregnancy. Many women become so exhausted that by dinnertime they are ready to go to bed for the night. The fatigue is similar to that of the flu but tends to last for much of the first trimester, much longer than with the flu.
Congestion and Headaches
The flu is caused by a virus that attacks the respiratory system and causes congestion, a runny nose and headaches. Surprisingly, this is also a pregnancy symptom. The hormonal changes and increase in blood supply that occurs in pregnancy also cause the membranes of the sinuses and nose to swell and produce mucus. The pressure can also cause headaches in some women.
Pregnancy Symptoms Exclusive of the Flu
Several other pregnancy symptoms that can start within a week of implantation do not occur with the flu. These symptoms include spotting, tender, swollen or sore breasts, the need to urinate frequently and mild pain or cramping in the abdominal area as the uterus stretches and grows.