First Signs Of Pregnancy: Before You Miss Your Period
Medically reviewed by Samara Laxineta, RN on July 23, 2019
- Most pregnant women begin feeling symptoms between weeks 5 and 6
- The most common symptoms are: nausea, fatigue, frequent urination, and changes in breasts
- The only way to know for sure if you’re pregnant is to take a pregnancy test
You’ve heard about the morning sickness, frequent urination, and other early signs of pregnancy. But what are the very first signs of pregnancy that might show up when you haven’t even missed your period yet?
Early pregnancy symptoms vary widely from woman to woman, and even in the same women across different pregnancies. In this article, we’ll explore some of the very first symptoms that may show up in the first few weeks of pregnancy.
It can be tempting to analyze your body for signs of pregnancy, but it’s important to keep in mind that the only certain sign of pregnancy is a positive pregnancy test. You may associate nausea, bloating, or fatigue with pregnancy, but the truth is, these symptoms can just as easily occur in women who are not pregnant.
How do you know for certain whether a given symptom is a sign of pregnancy? This is impossible, because most early pregnancy symptoms are caused by the hormone progesterone, which is elevated in the days before your period is due whether or not you are pregnant.
However, you can rule out the possibility of a symptom being caused by pregnancy. If you experience a symptom earlier than 9 days after ovulation (or 4 – 5 days before your period is due), it’s highly unlikely to be related to pregnancy—even if you do end up pregnant that cycle. The reason for this is that implantation does not occur until 9 days after ovulation. And until implantation occurs, you are not pregnant.
1. Late period
For most women, the first sign of pregnancy is a late period. But even a late period does not guarantee that you are pregnant. If your period is late, you should take a pregnancy test to confirm it. If your period is late but you have a negative pregnancy test, this means that you probably ovulated late this month.
A 1999 study published in the New England Journal of Medicine found that around nine percent of women experienced light bleeding or spotting during early pregnancy. Much of the time, there is no explanation for this bleeding.
You may have heard about something called implantation bleeding. This is the idea that when the fertilized egg burrows into the uterine lining, it may cause light spotting or bleeding around the time that your period is due. But the authors of the 1999 study found that when bleeding occurred, it was rarely on the day of implantation. They “found no support for the hypothesis that implantation can produce vaginal bleeding.”
While spotting can occur during early pregnancy, it’s not really a sign of pregnancy. That’s because spotting is more likely to occur in cycles that don’t end in pregnancy compared to cycles that do.
Despite what you may have heard about implantation cramps, while cramping may occur during early pregnancy, it’s also not considered a sign of pregnancy. This is because cramping also frequently occurs when someone is not pregnant.
There’s a physiological reason for this: the hormone progesterone, which can cause bloating and cramping. In the week before your period is due, progesterone levels are high. During pregnancy, progesterone levels increase even further.
Since premenstrual cramping and early pregnancy cramping are often caused by the very same hormone—progesterone—this means that cramping is not a reliable indicator of pregnancy.
4. Sensitive breasts
Hormone changes during your menstrual cycle can cause changes in breast tissue that makes your breasts feel tender. Some women swear that breast changes were their first pregnancy symptom. Common terms that women use to describe their symptoms include:
- Breasts feeling heavy or full
- Sore or sensitive nipples
- Tender breasts
- Increased breast size
The truth is that sore nipples and breast tenderness can happen during both conceptive and non-conceptive cycles. There aren’t scientific studies investigating whether breast pain in the days before your period due is more likely to occur in pregnant women.
5. Funny taste in your mouth
For some women, one strange early sign of pregnancy is a lingering metallic or bitter taste. Called dysgeusia, increased estrogen levels are the culprit.
While not all pregnant women experience this symptom, a 2002 study found that 93 percent of pregnant women experienced some form of altered taste during the first trimester.
Exhaustion is one of the most common symptoms of pregnancy, affecting up to 90 percent of pregnant women during the first trimester. This fatigue is caused by increased levels of the hormone progesterone, and the sleepiness can hit some women even before their period is due.
7. Elevated resting heart rate
Resting heart rate increases over the course of your menstrual cycle: it’s lowest during menstruation, increases as you approach ovulation, and increases further after ovulation. If you are not pregnant, resting heart rate falls during your next menstrual cycle.
If you are pregnant, resting heart rate remains elevated throughout your pregnancy. Throughout pregnancy, resting heart rate increases by about 25%, and the sharpest rise in heart rate occurs during the beginning of the first trimester.
8. Elevated basal body temperature
Basal body temperature is the lowest temperature your body reaches during a 24-hour period. When you’re not pregnant, your basal body temperature increases by about 0.5 degrees Fahrenheit after ovulation, falling again just before or during your next period.
The reason for this is that metabolic rate increases after ovulation and falls during your period. With a higher metabolic rate, your body generates more heat.
During pregnancy, basal body temperature does not fall as it typically would, but rather remains elevated through the first trimester.
You may not feel much warmer, since the increase in temperature is so slight. But if you use a sensitive thermometer to track your temperature, the increase should be apparent.
While morning sickness doesn’t typically start until around 6 weeks gestation (that’s 2 weeks after your missed period), some women start feeling nauseous much earlier—even before your period is due.
While nausea is very unpleasant, there is a silver lining: women who experience nausea during the first trimester have about one third the chance of miscarrying compared to those who don’t experience any nausea.
9. Excess saliva
A common complaint during the first trimester is excessive saliva. This symptom usually goes along with nausea, and there’s a good reason for it: experts believe that the saliva can help protect your mouth, teeth, and throat from stomach acid—which has a corrosive effect.
10. Increased sense of smell
If you suddenly can’t walk past a garbage can without holding your nose, and find you can no longer sit next to the coworker eating an egg salad sandwich … you might be pregnant.
Despite strong anecdotal evidence for heightened sense of smell, there’s a dearth of research looking into how common this phenomenon is or what might cause it.
11. Frequent urination
One of the earliest signs of pregnancy for many women, you may notice an increased need to urinate as early as 4 weeks of gestation (around the time your period is due). Rising levels of hCG cause increased blood flow to the kidneys, which in turn increases your urge to urinate.
Frequently asked questions about the first signs of pregnancy
How early are the first signs of pregnancy?
Studies show that most women begin to feel early pregnancy symptoms between the fifth and sixth weeks of pregnancy, with 89% of women feeling symptoms by the end of the eighth week. (How many weeks pregnant are you? Since pregnancy is counted from the first day of your last period—five weeks pregnant means one week after your missed period).
Can you be pregnant with no symptoms except a missed period?
Yes. If you think you might be pregnant and you’re worried that you don’t feel any different, remember: most pregnant women don’t experience any symptoms until a full one to two weeks after their missed period.
On the other hand, missing your period doesn’t necessarily mean you’re pregnant. Your period can be delayed because of late ovulation (since ovulation is what determines when your period comes) or an anovulatory cycle (a cycle where you don’t ovulate at all). Stress, illness, and travel can sometimes disrupt your usual ovulation pattern, causing your period to also be delayed.
If your period didn’t come when you expected it to and you are trying to conceive, it’s a good idea to treat yourself as though you are pregnant—until you confirm either way with a pregnancy test. Because if you did conceive, you may not feel the first signs of pregnancy for at least a few more weeks.
Aarthi Gobinath, PhD
She tackled the issue of sex bias in research by looking at why standard treatments for depression don't always work in the case of postpartum depression. Her work has been covered by Vice and Massive Science.