The most common symptoms of early pregnancy

You’ve recently had unprotected sex and now your period is later than usual. Wondering if you’re pregnant? The tricky thing about figuring out if you have pregnancy symptoms is that many signs are similar to PMS symptoms. It can also be difficult to know if your period is really late if you don’t know your average cycle length, or if your cycle length varies by a lot.

Here are the categories of pregnancy symptoms (1):
presumptive signs — possibility of pregnancy
probable signs — most likelihood of indicating pregnancy
positive signs — confirmation of pregnancy

Occasionally a person with an immense desire for, or fear of, pregnancy can develop presumptive, even probable, signs of pregnancy. This is known as a false pregnancy (pseudocyesis) and truly shows how the brain can influence physiology (1).
Sidenote: sympathetic pregnancy (also known as couvade syndrome) is when a partner experiences similar symptoms as the pregnant partner (2).

Most people notice the symptoms of pregnancy start about two weeks after conception, a couple of days after a missed period, or when there is a positive pregnancy test (1).

The most common symptoms of early pregnancy are increased urinary frequency, tiredness, poor sleep, and back pain (3).

Presumptive signs of pregnancy — possibility of pregnancy

Amenorrhea (no period)
Nausea — with or without vomiting
Breast enlargement and tenderness
Fatigue
Poor sleep
Back pain
Constipation
Food cravings and aversions
Mood changes
Heartburn
Nasal congestion
Shortness of breath
Lightheadedness
Elevated basal body temperature (BBT)
Spider veins
Reddening of the palms

Probable signs of pregnancy — most likelihood of indicating pregnancy

Increased frequency of urination
Soft cervix — Heager’s sign
Abdominal bloating/enlargement
Mild uterine cramping/discomfort without bleeding
Increased skin pigmentation in the face, stomach, and/or areola

Positive signs of pregnancy — confirmation of pregnancy

Fetal heartbeat
Visualization of fetus (ultrasound)
Positive hCG pregnancy urine or blood test

Vaginal bleeding occurs in 20 to 40% of pregnant people during their first trimester and can sometimes be confused with a light period (4,5).

Nausea during the beginning of pregnancy is commonly referred to as morning sickness due to a change in stomach function at this time — it usually, but not always, goes away in a few weeks (1). Even though it’s called “morning sickness,” nausea isn’t just confined to the morning.

Increase in urination in early pregnancy can be due to hormonal changes influencing bladder function and urinary output (6). Additionally, the cervix becomes softer by the sixth week of pregnancy — known as Hegar’s sign — and can be detected by a physician during a pelvic exam (1).

Pregnancy tests detect the hormone human chorionic gonadotropin (hCG), which is present in the blood and urine of a pregnant person. hCG is secreted by the placenta shortly after pregnancy begins (1). It’s best to take a pregnancy test to determine if you’re pregnant.

Track symptoms and pregnancy tests in Clue.


References

1. Jones RE, Lopez KH. Human reproductive biology. Academic Press; 2013 Sep 28.

2. TRETHOWAN WH, Conlon MF. The couvade syndrome. The British Journal of Psychiatry. 1965 Jan 1;111(470):57–66.

3. Foxcroft KF, Callaway LK, Byrne NM, Webster J. Development and validation of a pregnancy symptoms inventory. BMC pregnancy and childbirth. 2013 Jan 16;13(1):3.

4. Harville EW, Wilcox AJ, Baird DD, Weinberg CR. Vaginal bleeding in very early pregnancy. Human Reproduction. 2003 Sep 1;18(9):1944–7.

5. Norwitz ER, Park JS. Overview of the etiology and evaluation of vaginal bleeding in pregnant women. UpToDate. Waltham, MA. 2012.

6. Ravi T, Sharon EM. Maternal adaptations to pregnancy: Renal and urinary tract physiology. UpToDate. 2017