Am I Pregnant?

Signs That You May (or May Not) Be Pregnant

You’re sitting on the toilet, staring at a thin white strip.

You urge it to change colors, to tell you that you’re pregnant, the moment you’ve been waiting for—or you find yourself holding your breath, desperately hoping it won’t change, trying to think of any other reason why your period might be late. These can be the longest two minutes of your life.

Pregnancy can be complicated for a lot of reasons; the surge of emotions leading up to a pregnancy test is just the tip of the iceberg. Few women have a solid understanding of what goes on in their bodies, and many feel uncomfortable asking questions that could help them either avoid an unintended pregnancy or increase their chances of having a baby. Whether you’re looking forward to hearing the pitter-patter of little feet or hope to hold off on pregnancy for a while (or forever), all women should know the basic facts about pregnancy, fertility and their cycle.

Period Primer

It may not be your favorite part of the month, but your period can tell you more about your body than you might realize. Careful attention to your cycle can tell you when you’re most fertile and can give you some insights into your overall health.

Your menstrual cycle begins on the first day of your period and ends the day before your next period. The average cycle length is 28 days, but it’s normal to have a cycle that lasts anywhere from 21 to 35 days.

During your cycle, your body releases hormones that give directions to your ovaries, where eggs are stored. The hormones cause an egg to be released from one of your two ovaries (your ovaries take turns releasing an egg each month). The egg travels down the fallopian tubes, and is made available for fertilization in a process called "ovulation."

If you’re trying to conceive, ovulation is the part of your cycle that deserves a lot of attention. Ovulation—which happens about halfway through your cycle—is the time when you are most fertile. If you pay attention to your body, you may be able to tell when you are ovulating: Women often experience pain on one side of the abdomen, breast tenderness and a boost in sex drive during ovulation. Ovulating also changes the consistency of vaginal secretions, which will become thinner, stretchier, and more slippery—much like the consistency of egg whites—during ovulation.

Meanwhile, your uterus will develop a nutrient-rich lining, meant to nurture a fertilized egg. If you do not get pregnant, your uterus will shed that lining, which is your period. Periods last an average of four days long, but a period lasting anywhere from two to seven days is also normal.

Keep in mind that your period can be disrupted for many reasons; your cycle is orchestrated by a complex set of processes within your body, and activities that affect the balance of hormones can affect your period. Many women find that hormonal birth control (like birth control pills) makes their periods lighter and more regular, and you may find that you have an irregular cycle for a few months after going off birth control. Stress, extreme weight gain or loss, and a particularly heavy exercise schedule may cause you to miss a period.

Pregnancy: The Birds and the Bees

If you fell asleep in Sex Ed, here’s the lowdown: For you to become pregnant, sperm needs to reach the egg. Usually, pregnancy happens as a result of vaginal intercourse — a man orgasms and ejaculates inside a woman’s vagina. However, it’s possible to get pregnant through certain kinds of sex play, as anything that introduces semen into the vagina could potentially lead to pregnancy. Fingering or sex toys could cause pregnancy if objects entering the vagina have semen on them; however, oral sex or anything “above the belt” will not cause pregnancy.

Timing is also important when it comes to pregnancy, as your window of fertility is fairly narrow. The egg is only available for fertilization when you are ovulating, so for you to get pregnant, the egg must be fertilized 12 to 24 hours after it has been released from your ovaries. But that doesn’t mean there’s only one day out of the month that you can get pregnant: Sperm can live for up to five days in the body. In other words, unprotected sex up to five days before ovulation can result in pregnancy. Because it can be hard to tell when you're ovulating, having repeated sex around the time of possible ovulation can increase your chances of conceiving, if you’re trying to get pregnant.

Signs You Might Be Pregnant

You don’t have to wait for a bump to know you’re pregnant; your body starts changing in subtle ways within weeks of conception.

The first clear sign you’re pregnant is a missed or delayed period. Rather than shedding the lining of your uterus, your body uses that lining to nourish the fertilized egg.

Another sign to look for is unexpected spotting or light bleeding about six to 12 days after conception. This is called "implantation bleeding" and happens when the fertilized egg burrows into the uterine wall. Because implantation bleeding can occur around the same time as their expected period, some newly pregnant women confuse this with their actual period. However, this is not a true menstrual cycle as you can’t menstruate while pregnant. Keep in mind that bleeding can happen for many reasons. It might be your actual period, or it could be due to starting or switching your birth control pill, a vaginal infection or rough sex.

There are a number of other physical symptoms that suggest you’re pregnant. Some women get swollen or tender breasts one to two weeks after conception; others become fatigued just a week after conception; nausea (“morning sickness”) often begins two to eight weeks after conception and generally lasts through the first trimester; headaches can be caused by changes in your hormones that occur as a result of pregnancy.

But it’s best not to read too much into any of these symptoms, as all could be caused by many things other than pregnancy—including PMS. The only way to tell for sure is by taking a pregnancy test.

Get the Answer: Pregnancy Tests

There are a few different types of pregnancy tests, but they all have one thing in common: They work by checking for a pregnancy hormone called human chorionic gonadotropin (hCG). hCG is made when the fertilized egg implants in the uterus. This happens about six days after conception for most women, but can happen as late as 12 days after the egg is fertilized.

If you want to do a pregnancy test on your own, you can buy a home pregnancy test, which measures the amount of hCG in your urine. Urine tests can’t detect hCG until about two weeks after conception, so doctors recommend you don’t try a home pregnancy test until the first day of your missed period. The later you wait, the more likely the test is to be accurate. If you are pregnant, the level of hCG in your system builds up with each passing day.

If you take the pregnancy test too early (i.e., before the first day of your missed period) or don’t follow the instructions that come with the test, it is possible to get a negative result even if you are pregnant. Most urine tests don’t work until the first day of your missed period or later, and have a set of instructions you need to follow carefully. Some pregnancy tests, such as the Clear Blue First Response, are sensitive enough to detect hCG up to foiur to five days before your period is missed. If you get a negative result, wait a week and perform another test, just to be sure.

If you performed the test correctly and took it at the correct time, a positive test almost certainly means that you’re pregnant—these days, home pregnancy tests are as accurate as the urine tests you get in the doctor’s office. If you see your doctor for a pregnancy test, he or she will likely take a blood sample. Blood tests are the earliest way to tell whether you’re pregnant, and can be performed about six to eight days after you ovulate.

Your Conception Questions, Answered

Get the facts on some common questions about sex and pregnancy.

Can I get pregnant if I have sex during my period?

Yes, it is possible to get pregnant if you have sex during your period, though you’re not as likely to get pregnant from having unprotected sex during your period as you are at another point in your cycle. Sperm can live in the body for up to five days, so you may get pregnant if you ovulate within a week of unprotected sex. Ovulation can be tough to track, especially if you have an irregular cycle. Bottom line: You should use contraception every time you have sex to avoid unintended pregnancy, even when you are on your period.

If I missed my period, am I pregnant?

If you have had unprotected sex recently and missed your period, take a home pregnancy test on or anytime after the first day of your missed period. If you want an answer sooner, your doctor can administer a blood test six to eight days post-ovulation. Keep in mind that a missed period can be caused by many things other than pregnancy, like stress, extreme weight change, fatigue and hormone fluctuations.

If my partner pulled out before ejaculating, can I still get pregnant?

If your partner did not ejaculate inside of you, the chances of you becoming pregnant are small. In fact, some couples practice withdrawal as a method of contraception: The man pulls out before he ejaculates. However, this is not a recommended—nor effective, according to medical studies—form of contraception as it requires careful timing and a hefty dose of willpower. Also, some experts think that pre-ejaculate, the liquid that seeps out of the penis right before a man ejaculates, might have enough sperm to fertilize an egg.

If I didn’t have an orgasm, can I still get pregnant?

Yes, you can. A woman’s orgasm does not have an impact on her chances of becoming pregnant. However, pregnancy is unlikely if the man does not orgasm; a man usually ejaculates while having an orgasm (though male orgasm does not have to be accompanied by ejaculation—the two can happen independent of each other), and the semen in the ejaculate is needed for pregnancy to happen.

Can I get pregnant if my partner ejaculated into a hot tub?

If your partner ejaculated into the water, but not inside of you, your chances of becoming pregnant are vanishingly small: Sperm may be good swimmers, but there’s no way they can swim all the way through a pool or hot tub. However, if you have sex in a pool or hot tub and your partner ejaculates inside of you, or if semen enters your vagina through other sex play, pregnancy is a possibility.

If I use contraception, can I still get pregnant?

The only surefire way to prevent pregnancy is to practice abstinence: No method of birth control is 100 percent effective, but certain forms of contraception are better than others. However, you can greatly reduce your chances of becoming pregnant by using birth control exactly as instructed every time you have sex.

Here are a few need-to-know facts about contraception that people often forget:

Do not use an oil-based lubricant if you use latex condoms, as it often causes condoms to break.
Use a condom the entire time you are having sex: withdrawal—having intercourse then pulling out or putting on a condom right before ejaculating—is not a reliable form of contraception.
If you are on the birth control pill, you need to take the pill at the correct time every day; if you miss a pill, you should use a backup method of contraception temporarily.

If you are unsure about how to use contraception, talk to your doctor.

I have irregular periods. How does that affect my chances of getting pregnant?

Getting pregnant depends on ovulation, not on how regular your menstrual cycle is. So as long as you are ovulating normally, your chances of getting pregnant should not be impacted. That said, having an irregular period makes it difficult to predict when you are ovulating, and might even be a sign you are not ovulating at all.

Sometimes an irregular cycle indicates that you have an underlying health problem, like a thyroid disorder or polycystic ovary syndrome (PCOS), a common cause of infertility. If your cycle is shorter than 21 days, longer than 45 days, your period lasts for more than seven days or if you go 90 days without a period, talk to your doctor, whether or not you’re actively trying to conceive.

My period this month was really light—more like spotting. Could I be pregnant?

If you’ve had vaginal sex, especially unprotected sex, since your last regular period and your period this month is earlier and/or lighter than usual, you may be experiencing implantation bleeding. Implantation bleeding is different for everyone; many women don’t notice it at all. For those who do, some women have light spotting for a few hours, while others have it for a few days. However, there are many other reasons to have a light period, like intense physical activity or changes in your hormones. If it’s been at least two weeks since you think you might have conceived, you might want to take a pregnancy test or call your doctor.

How to Avoid Pregnancy

About half of the pregnancies in the U.S. are unintended. But there are steps you can take to avoid becoming part of that statistic. If you do not want to become pregnant, make sure you use contraception correctly every time you have sex. If you are on birth control, take it as your doctor instructed, and use a backup method like condoms if you forget to take it at the right time. Remember that while all contraception works to prevent pregnancy, only condoms can protect you from sexually transmitted infections (STIs).

If contraception fails, you can take an emergency contraception pill (also called the “morning-after pill”) up to 120 hours (five days) after unprotected intercourse. Morning-after pills contain a high dose of the same hormones found in birth control pills. This hormone surge disrupts the process of ovulation, which means that an egg will not be released, so there is no way for it to be fertilized by sperm. Moreover, scientists have found that morning-after pills make it harder for sperm to travel through the reproductive tract, which lowers the likelihood that sperm and egg will meet. Since emergency contraception works by preventing conception before the egg is fertilized, morning-after pills are defined as birth control, not as a form of abortion.

Morning-after pills might be a good option if the condom breaks or slips, if you had unprotected sex, or if you forgot to take your birth control pills as instructed. There are two types of emergency contraception pills available for purchase over-the-counter, without a prescription: Plan B and Next Choice. Look for them at your local drugstore or Planned Parenthood health center. Women under the age of 17 no longer need a prescription to buy morning-after pills. If you do need to take emergency contraception, keep in mind that the sooner you take the pill, the more effective it will be at preventing pregnancy.

Margot Hedlin is a science and health writer living in San Francisco.

Reviewed by Elaine Brown, MD on January 8, 2014