How Late Can a Period Be Before You Know You’re Pregnant?

Medically Reviewed on 12/14/2022

What is a late period?

A late period is when a woman's menstrual cycle doesn't start as expected, with a normal cycle lasting between 24 to 38 days. When a woman's period is seven days late she may be pregnant although other things may cause a late or skipped period.
A late period is when a woman's menstrual cycle doesn't start as expected, with a normal cycle lasting between 24 to 38 days. When a woman's period is seven days late she may be pregnant although other things may cause a late or skipped period.

If your period is late or you’re wondering if you’re pregnant, the days can tick by rather slowly. How long do you have to wait before taking a pregnancy test? The instructions on home pregnancy tests often talk about “your missed period.” What do they mean?

A late period can be a sign of pregnancy, but it can also indicate many other things, such as stress, illness, and the use of certain medications. It is always smart advice to talk to your doctor if you are unsure.

A missed period means you expected your menstrual bleeding to have started yesterday, and it still has not started. So, the day of your expected period depends on what your normal menstrual cycle looks like and when your last period started. 

Your menstrual cycle is the time from the first day of your period to the day before your next period starts. The average cycle is 28 days, with a pattern that looks something like this:

  • Day 1 – The tissue lining your uterus (womb) breaks down and leaves your body through the vagina. This bleeding is your period, and it lasts 4 to 8 days for most women.
  • Day 8 – The lining of the uterus begins building up again to be ready to nourish a fertilized egg. Your body does this every month to prepare for a potential pregnancy.
  • Day 14 – An egg is released from your ovary in a process known as ovulation. You are most likely to get pregnant if you have sex on the day you ovulate or in the three days before. While a man’s sperm can live 3 to 5 days inside you, your egg can only live 1 day if it is not fertilized by a sperm.
  • Days 15 to 24 – The egg travels down a fallopian tube toward the uterus. If the egg joins with a sperm, the fertilized egg will attach to the lining of your uterus. This is called implantation and is the moment pregnancy begins.
  • Day 24 – If the egg has not joined with a sperm, it starts to break apart. Your hormone levels drop, signaling your uterus that it will not need to support a pregnancy this month.

Some women’s menstrual cycles last the same number of days every month. These women can accurately predict the day their period will start. Other women have a menstrual cycle that is a little different each month. Your period is still considered regular as long as it comes every 24 to 38 days.

Symptoms of a late period and pregnancy

The symptoms of a late period will be obvious to many women who menstruate regularly. If you were expecting your period, and it doesn’t begin, you’ll know it’s late. Not all periods arrive like clockwork, and it’s very normal for periods to occur on a slightly different schedule. Pregnancy isn’t the only thing that can cause a late or skipped period. But if you’re wondering whether your missing period might mean you’re pregnant, you can look for other early symptoms of pregnancy. During the first 8 weeks of pregnancy, many women experience:

1. Fatigue

During the first trimester (weeks 0 to 13 of pregnancy), your body produces large amounts of a hormone called progesterone. This can make you feel sleepy. Even during the first week after conception, you may feel more tired than usual.

2. Spotting

Implantation bleeding is one of the earliest signs of pregnancy. It is very light bleeding, often called “spotting”, that happens as a result of the fertilized egg implanting (attaching) to the uterine wall. Implantation is usually 6 to 12 days after conception, or the moment the egg is fertilized by a sperm. 

Some women also have mild abdominal cramps during implantation. Other women don’t notice any symptoms with implantation.

3. Breast Changes

You may see changes in your breasts as early as 1 to 2 weeks after conception. Your breasts may be swollen and tender to the touch. You may have soreness or a feeling of fullness in your breasts.

4. Headaches

The rapid rise in hormones and blood flow during pregnancy can lead to mild headaches even before a missed period.

5. Missed Period

This is often the first symptom women notice. If you are pregnant, you will probably not have regular menstrual bleeding. Some women do have spotting during pregnancy, but it would probably be much lighter and shorter than your usual period.

6. Nausea

Morning sickness typically shows up 2 to 8 weeks after conception and goes away by about 14 weeks. Though it is called morning sickness, nausea during pregnancy can happen at any time of the day or night. For many women, symptoms are the worst when they first get up in the morning. Some women experience vomiting with morning sickness, but others do not. 

7. Frequent urination

Around 6-8 weeks after conception, you may start to feel like you have to pee much more often than usual. This symptom is likely to continue for the rest of your pregnancy.

Causes of a late period and pregnancy

Pregnancy happens when an egg is fertilized by a sperm. But pregnancy is not the only reason for missed or late periods. Some other possible causes include:

What are the signs of a hidden pregnancy? 

You may not know that you are pregnant. This is known as a "cryptic" or "hidden" pregnancy. Some people who have hidden pregnancies get irregular periods. Others don't recognize the signs of pregnancy. Still others may have received a negative pregnancy test result. A hidden pregnancy is simply a pregnancy that is not recognized. Some women have reported to the emergency room for pelvic pain, only to wind up in labor hours later.

Since a "hidden" or "cryptic" pregnancy is the same as any other pregnancy, the same common signs of pregnancy will often be present, whether or not they are recognized.

SLIDESHOW

16 Early Signs & Symptoms of Pregnancy: Could You Be Pregnant? See Slideshow

Diagnosis and tests for a late period and pregnancy

Home pregnancy tests check your urine for a hormone called human chorionic gonadotropin (hCG) that is only present when you’re pregnant. The body starts making hCG at implantation, and many home pregnancy tests can detect hCG around the day of your expected period.

However, it is common to get a false negative in the first few days after a missed period. The amount of hCG in your body increases daily in early pregnancy. If you test too early, there might not be enough hCG for a positive test. Testing one week after a missed period is most likely to give you accurate results.

If you’ve had two home pregnancy tests come back negative and still think you’re pregnant, check with your doctor. They can order a blood test that looks for the same hormone but can detect it earlier in the pregnancy. Blood tests can give accurate results as soon as 6 to 8 days after ovulation.

If your pregnancy tests come back negative, but you still haven’t had a period, talk to your doctor to determine what might be the cause and if any additional tests or treatment are needed. If you’re trying to conceive, your doctor can perform additional tests or make other suggestions.

What can throw off a pregnancy test? 

Home pregnancy tests don't always work right the first time. Although they have about a 99% rate of accuracy when used correctly, they still sometimes produce false results. You may have to test yourself two or three times to be certain of their results. These tests can error as either false positive or false negative results. Sometimes the tests accurately report a pregnancy that is not viable, so the result goes back to negative if you test days later. Also, fertility medications can leave hCG in your bloodstream, complicating pregnancy test results. Women who have recently given birth are more likely to have leftover hCG inside their blood, and this makes a false positive test result more likely.

A false negative test can result from many different things. First, you may not be using your testing kit correctly. Be sure to read over the instructions carefully and look for any missed steps. Second, you may have used the kit too early. This can lead to a false negative test result. Third, you may have miscalculated your menstrual cycle, especially if you are used to having an irregular period. Finally, both having diluted hCG and having too much hCG in your bloodstream can throw off test results and lead to a false negative.

Treatments for a late period and pregnancy

In general, if you’ve missed a period and you know you’re not pregnant, you don’t need specific treatment or care. However, if you were having a regular cycle and you’ve stopped, if you’re experiencing bleeding at unexpected times, if it’s been more than 45 days since your last period, and if you have additional symptoms that point to other concerns, your doctor will likely look into treatment options. Depending on the cause, your doctor may prescribe hormone therapy like birth control pills or other medication, or they might be able to suggest lifestyle changes to help you have a regular period cycle. 

If your late period is a sign of pregnancy, your doctor can help you come up with a treatment plan to be sure you receive proper care and regular checkups throughout your pregnancy.

How many days after my period can I get pregnant?

Ovulation or the fertile window occurs between days 12 and 20 of your cycle, and studies have reported that you are more likely to become pregnant during this time because an egg is released from your ovary.

The exact time depends on the length of your cycle.

  • If your menstrual cycle is of 28 days, you will ovulate near the 14th day, and your most fertile days are probably days 12, 13, and 14.
  • If your menstrual cycle is around 35 days, ovulation will happen near the 21st day, and your fertile days are days 19, 20, and 21.
  • Regardless of how long your cycle is, most women ovulate 10 to 16 days before the start of their next menstrual cycle.
  • You can become pregnant if you have intercourse five days before ovulation and one day after ovulation.
  • If there is live sperm in the fallopian tubes during ovulation, you are much more likely to become pregnant.

You can use fertility awareness as a natural birth control method. This means that if you have a period that lasts between 26 and 32 days, the days 8 through 19 will be the most fertile days. This method, however, works best if you have regular menstrual cycles. There is a one to five percent chance of getting pregnant.

Though the fertile window is when you have the best chance of becoming pregnant, you can become pregnant outside of it. Not every woman's cycle is the same number of days and neither is their window.

Is there a possibility to get pregnant just after my period has finished?

Getting pregnant right after your period is unlikely but not impossible. The chances of becoming pregnant are lower immediately following periods than a few days or a week later.

  • There is no "safe" time of the month when you can have sex without contraception. However, there are times during the menstrual cycle when you are most fertile and most likely to conceive.
  • The fertile days can last for up to three to five days after your period has ended. The likelihood of becoming pregnant immediately following a period is determined by the length of the menstrual cycle and the length of the period. If your period is long, you may only have a few or no days after your period ends.
  • You may ovulate just days after your period if your menstrual cycle is short, such as 22 days. Sperm can survive in the fertile cervical mucus for five to seven days. You may be able to become pregnant if you ovulate a little earlier than usual.
  • If your cycle is irregular, you may become pregnant right after your period.

Ovulation calculator

How to use this ovulation calculator tool

  • Pick a date on the calendar that matches the day you started your last period
  • The calendar will display your estimated ovulation date, marking it in red.
  • The days leading up to your ovulation date will appear marked in purple; those are the days you are likely the most fertile.
  • If you have records of how long your own menstrual cycle lasts, change the default number of 28 days in the dropdown menu in the results box for a more accurate calculation.

5 symptoms of ovulation

The female reproductive process of releasing a mature egg from the ovaries and transferring it to the fallopian tubes for insemination is called ovulation. Every month, about two weeks after menstruation begins, one egg is released.

The following are some common signs of ovulation:

  • Increased sex drive, particularly in the middle of the cycle, is a common symptom of ovulation.
  • You may experience slight soreness in the breasts about halfway through the cycle, which could be an indication of ovulation.
  • Your basal body temperature may rise by about 0.5 degrees during ovulation due to a surge in progesterone hormones, especially while resting. Keeping track of your basal temperature every morning can help you determine the most fertile days of the month.
  • You may experience ovulation-related symptoms in your ovaries, such as mild aches to sharp pain twinges. You may suffer from a condition called mittelschmerz, in which you experience ovulation as one-sided backache or tender area. The sensation can last anywhere from a few minutes to several days.
  • On ovulation days, there are changes in the vaginal discharge or cervical mucus. The changes are caused by the rising estrogen levels in the body, which are required for egg release.

Ovulation and calendar charting may not be perfect, but they may be fairly accurate. If you are unsure about your last menstrual period or have irregular cycles, the results could be incorrect. The calculators can provide an estimate of the most likely ovulation time. Combining them with ovulation symptoms may be beneficial.

These tools are based on averages, and even if you are accurately charting your periods, cycle length and ovulation date may vary with each cycle. These tools are especially useful if you have irregular periods because they calculate average cycle length and give them a wider fertility window in which to conceive.

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How early can I know my symptoms of pregnancy?

Each woman's early pregnancy symptoms are usually unique. You may notice the first signs of pregnancy within a week or two of conception, whereas others may not notice anything for months.

It depends on your ability to detect changes in the body and how sensitive you are to those.

A blood test, which can detect pregnancy as early as one week after conception, is always an option.

During studies, women trying to conceive kept daily records of their symptoms from the time they stopped using birth control until they were eight weeks pregnant. This was based on the first day of their last menstrual period. The outcomes were:

  • By the time they were five weeks pregnant, half of them had some pregnancy symptoms
  • By six weeks, 70 percent of women had symptoms
  • By eight weeks, 90 percent of the participants had developed symptoms
  • A missed period is usually the first sign of pregnancy
  • Nausea, vomiting, fatigue, frequent urination, and breast tenderness and swelling are the most common symptoms; these symptoms can range from mild to severe

Some pregnancy symptoms, such as nausea and vomiting, can appear as early as a few days after conception, even before a positive pregnancy test.

Spotting or cramping

  • Implementation spotting and cramping may occur 6 to 12 days after sexual intercourse according to the American Pregnancy Association.
  • It is the process by which the embryo implants on the uterine wall.
  • Implementation bleeding can appear to be a lighter or shorter period. This symptom, however, is not common in all women.

Hormonal changes

  • Breasts may feel sore, swollen, and tender as early as one to two weeks after conception due to hormonal changes and increased blood flow. They may appear larger, fuller, and heavier, and their appearance may change. Hormone imbalances may cause areolas to appear darker.
  • Early in pregnancy, the abrupt rise in hormones can cause headaches.
  • Changing hormones may interfere with sleep patterns during the first few weeks of pregnancy.
  • Early in pregnancy, hormonal changes may cause food cravings or aversions. These changes in food preferences may last for the duration of your pregnancy.
  • Mood swings are common during pregnancy due to hormonal changes. This can happen as soon as a few weeks after conception.

Morning sickness and tiredness

  • This is the most common symptom, and it usually appears between two and eight weeks after conception.
  • Nausea can be accompanied by vomiting and exhaustion. Because this symptom is not necessarily limited to the early morning hours, it is regarded as the most difficult pregnancy symptom to deal with.

Raised basal temperature

  • You may keep a record of your morning basal temperature to chart their cycle; there is usually a temperature drop the day before your period.
  • If you have a high basal body temperature even when you are expecting your period, it could be a sign of a missed period and pregnancy.
  • This method is, however, not recommended because it is susceptible to many environmental factors.

Frequent urination

  • The kidneys produce more fluid and fill the bladder more frequently during pregnancy.
  • Between weeks four and six, you may notice that you are going to the bathroom more frequently.

To increase your chances of getting pregnant, try to have sex during the fertile window. It is necessary to engage in sexual activity regularly. Pregnancy rates are the highest among partners who have intercourse every two to three days during the month.

Avoid smoking and alcohol and limit your caffeine intake. Tobacco and alcohol use in men can impair sperm quality and thus reduce fertility. It is critical to maintaining a healthy weight. Being overweight or underweight can hurt ovulation.

Medically Reviewed on 12/14/2022
References
SOURCES:

American Pregnancy Association: "Early Signs of Pregnancy."

Cleveland Clinic: "Cryptic Pregnancy."

Cleveland Clinic: "Causes of a False Positive Pregnancy Test."

Kids Health: "Irregular Periods."

Office on Women's Health: "Knowing If You are Pregnant."

Office on Women's Health: "Your Menstrual Cycle."

Office on Women's Health: "Prenatal Care and Tests."

National Health Service: "How can I increase my chances of getting pregnant?"

Tanya Tantry, MD: "What Causes False-Negative Pregnancy Tests?"

University of Michigan: "Missed or Irregular Periods."

Fertility Coalition. Your Fertility right time for sex. https://www.yourfertility.org.au/everyone/timing

American Pregnancy Association. Can You Get Pregnant on Your Period? https://americanpregnancy.org/can-i-get-pregnant-if/can-you-get-pregnant-on-your-period/

Wilcox AJ, Dunson D, Baird DD. The timing of the "fertile window" in the menstrual cycle: day specific estimates from a prospective study. BMJ. 2000;321(7271):1259-1262. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC27529/

Journey House Pregnancy Resource Center. How Soon After Sex Can I Know If I’m Pregnant? https://journeyhouseenid.org/how-soon-after-sex-can-i-know-if-im-pregnant/

WebMD. Ovulation Calculator. https://www.webmd.com/baby/healthtool-ovulation-calculator