Procedure and Accuracy of Urine Pregnancy Test
A urine pregnancy test measures the amount of human chorionic gonadotropin (hCG) in the urine. hCG is a hormone found only in a pregnant woman. Home pregnancy tests are urine pregnancy tests and are a popular way to detect pregnancy. There is a wide variety of tests available in the market today and are a convenient way to find out if one is pregnant.
HCG is secreted after implantation by those cells which go on to form the placenta. It is best to take a home pregnancy test (HPT) about a week after you miss your period. Taking the test early on in pregnancy can result in a false negative result. Almost all urine tests will give you a proper reading if you test about two weeks after you ovulate. The best time to take the test is first thing in the morning as the hCG samples are most concentrated at this time. The test can be performed within five minutes or so and only one or two drops of urine are required. You will either have to pass urine directly onto the chemically treated strip or use a dropper to place the urine sample on the stick. If the pink or blue lines on the strip change color, the test is positive. Some tests have a symbol on them which denotes pregnancy. Most tests have a control indicator (a second line) which indicates whether the test is valid.
When Does the Urine Home Pregnancy Test Become Positive
A urine home pregnancy test HPT usually becomes positive within a week or so after implantation, or around the time of your expected menstrual period. It becomes positive about 12-14 days days after ovulation and fertilization.
Typical pregnancy symptoms usually do not show up until after the blood hCG has reached significant enough levels.
An hCG level below 5 mIU/ml is considered negative, and a level above 25 mIU/ml is positive. You can’t be sure that a blood hCG level between 5 and 25 mIU means it’s a positive test because an hCG level between 5 and 25 mIU is considered ‘equivocal,’ which means we don’t know if it’s negative or positive.
At a blood hCG level between 5 and 25, most doctors probably repeat the test 2-3 days later. A rise above 25 mIU means that you are pregnant.
Positive Pregnancy Test: When and How Long After Implantation
A pregnancy test can show a positive result a few days after implantation has occurred. Most women who want to get pregnant are very keen to take a home pregnancy test (HPT) to see if the result is positive. Depending on your body and the levels of hCG hormone, early pregnancy can be detected by a pregnancy blood test as soon as 3-4 days after implantation. Usually, a urine home pregnancy test takes a few days longer to detect a pregnancy and may show a positive result as soon as 5-7 days after implantation.
Even if the home pregnancy test result is negative, it doesn’t necessarily mean that you are not pregnant. How soon an early pregnancy can be detected depends on the levels of the hormone called human chorionic gonadotropin (hCG). This hormone is produced during pregnancy. Blood and urine pregnancy tests check for elevated levels of hCG which start to rise right after implantation. A positive urine home pregnancy test will undoubtedly mean that you are pregnant and should visit your doctor for hCG blood test.
Most home urine pregnancy test kits advise that you should wait until the first day of your missed period before taking the test. This is when levels of hCG will usually be high enough for the majority of pregnancy testing kits to show a positive pregnancy result if you have conceived. However, some urine pregnancy testing kits are more sensitive and may be able to show a positive result and detect early pregnancy quite soon after implantation.
If you have already waited for a few days after your missed period to take a pregnancy test, and it is still negative, chances are that you are not pregnant.
You may want to take a pregnancy test, but you probably have questions such as: How long after implantation can I test? How long do I have to wait after a missed period before I take a test? In this article, you will find out how early you can detect pregnancy using at-home pregnancy testing kits. You will also learn about the other early signs of pregnancy that can help determine if implantation has taken place.
How Long After Implantation You Need to Take a Pregnancy Test
How early you can take a pregnancy test depends on a number of factors such as the sensitivity of the home pregnancy test (HPT), levels of human chorionic gonadotropin (hCG) in your body, and the regularity of your menstrual cycle.
A pregnancy test can only become positive when an egg is fertilized after ovulation. According to the American Pregnancy Association, ovulation happens about 11 to 21 days from the start of your last period. 1 At ovulation, an egg is released and lives for up to 24 hours in the fallopian tubes waiting for a sperm that lives long enough to fertilize it. Some signs of ovulation include discharge, light abdominal cramping, and some ovulation spotting.
When the fertilized egg attaches itself to the wall of your uterus, implantation occurs. As soon as implantation happens, your body produces hCG and the pregnancy hormone can be detected in a pregnancy test. At the same time, you may have other signs of implantation such as light spotting that lasts a day or two, mild cramping, tender breasts, and an increased need to pee.
The length of time after implantation you need to take a pregnancy test to check if it’s positive or not depends on the sensitivity of the pregnancy test that is carried out. The two types of pregnancy tests to check for early pregnancy are:
- Urine hCG pregnancy test kits that you use at home and show up a mark to indicate a positive pregnancy test or a negative test result.
- Pregnancy blood tests at the doctor’s office to check for hCG in blood serum in order to detect a pregnancy.
Urine hCG test – when is it positive after implantation?
Some of the most sensitive urine pregnancy test kits can detect early pregnancy in less than a week after implantation. The European Society of Human Reproduction and Embryology, found that urine pregnancy testing kits will usually show a positive result 3-4 days after implantation. By 7 days (the time of the expected period) 98% of pregnancy testing kits will be positive. 13
Urine pregnancy test kits have an hCG sensitivity of 25 mlU/ml (sensitivity of 25 units per litre). The American Pregnancy Association say that a reading of more than 25 mIU/ml in urine indicates pregnancy. 2
The levels of hCG are detectable a few days after implantation. For example, a report published in a German medical journal said that sensitive pregnancy testing kits can detect hCG as early as 4 days or even 10 days before your next period is due. 3
According to Dr. Nivin Todd on WebMD, implantation occurs 3-4 days after the egg is fertilized. This may result in implantation bleeding which can be one of the earliest signs of pregnancy. Dr. Todd says that hCG levels will show up in most urine tests from as early as 7 days before you expect your next period. 4
Sometimes, urine home pregnancy tests show up “false-negative” results because not enough hCG hormone has been detected yet. This means that you could still be pregnant even though the pregnancy test shows up as negative. However, in a few days, the pregnancy test will become positive in women if implantation has taken place.
You can test for pregnancy using a urine pregnancy test as early as a week before your next period is expected. Even if the results are negative, you shouldn’t lose hope. Take another urine pregnancy test after 5-7 days to see if it becomes positive. According to Lab Tests Online, if you are pregnant, an early positive urine pregnancy test will be reliable 10 days after your missed menstrual period. 5
Blood hCG Level and early pregnancy test
A pregnancy blood test will be positive 2 or 3 days before a urine pregnancy test. Pregnancy blood tests check the levels of the hCG hormone and they are more accurate than urine pregnancy tests as they can show the exact levels of hCG.
Doctors also use hCG levels to determine how many weeks you are pregnant and to monitor your health during pregnancy.
A blood pregnancy test will become positive very soon after implantation. According to Dr. Melissa Conrad Stöppler on MedicineNet, positive pregnancy blood test result can show up as early as one week after conception. Because implantation happens 3-4 after conception, you might get early pregnancy blood test results that are usually positive within 3 or 4 days after implantation. 6
In very rare circumstances, you might have a “false-positive” pregnancy test result. Dr. Stöppler says that medication, tumors, or other conditions can show up as a positive pregnancy test when there is, in fact, no pregnancy.
Pregnancy Test Soon After Implantation – How Accurate Is It?
A positive pregnancy test is almost certainly correct and is usually very accurate. However, you always need to follow the instructions of the home pregnancy test correctly.
Doctors from the National Health Service say that if the pregnancy test results are positive, then you are probably pregnant. However, a negative test result is less accurate and isn’t necessarily an indicator that you’re not pregnant. Sometimes, taking the pregnancy test too soon after implantation doesn’t allow for high enough levels of hCG hormone to develop. 7
Pregnancy tests can show a positive result when the concentration of the pregnancy hormone (hCG) is high enough to be detected in a blood test or urine sample.
According to Dr. Traci Johnson on WebMD, there are 6 factors that can affect how accurate a pregnancy test is soon after implantation. Some of these are: 8
The European Journal of Epidemiology says that smoking and being overweight can also negatively affect hCG levels. This makes it harder to test for early signs of pregnancy soon after implantation. 10
However, if you are pregnant, then pregnancy test result is usually positive within 7-10 days after you have missed a period.
How to Test for Pregnancy Soon After Implantation
Most women use at-home urine pregnancy test kits because they are cheaper and quicker than making an appointment with your doctor for a pregnancy blood test. These will test positive for pregnancy when hCG levels reaches at least 25 mIU/ml.
To use a urine pregnancy test soon after implantation to check if it tests positive, this is what you should do:
What do Pregnancy Test Results Mean After Implantation?
Positive pregnancy results usually mean that you are pregnant. Most home pregnancy testing kits show the results by means of a line to indicate a positive or a negative result. Dr. Traci Johnson on WebMD says that even if the line for a positive pregnancy test result is very faint, it still means you are pregnant. 8
If your pregnancy test is positive, then it means that you should make an appointment to see your doctor. The earlier you can arrange for prenatal care, then the better health you and your baby will enjoy during pregnancy.
Negative pregnancy results may not necessarily mean that implantation hasn’t happened. You could still be pregnant because you tested too soon after implantation or you took the test the wrong way. Dr. Traci Johnson recommends retesting for a positive result in a week to check for pregnancy.
If the HPT still tests negative over 10 days after your missed period, you should speak to your doctor. A late or missed period could be a result of a hormonal imbalance as well as emotional stress, excessive weight loss or gain and problems with pelvic organs. 12
Early Signs of Pregnancy Very Soon After Implantation
Even before an hCG pregnancy test becomes positive, you may have some signs of implantation that show up before a pregnancy test confirms that you are pregnant.
Implantation spotting. Many women experience implantation spotting as one of the earliest pregnancy signs. Implantation bleeding looks like very light spotting that could be a rusty brown or light pink color. Spotting associated with implantation usually last up to 2 days.
Implantation cramping. Around the time when the fertilized egg attaches to the uterine lining you might experience mild cramping. Implantation cramping usually happens just before or just after you notice implantation spotting.
Breast tenderness. Doctors from the American Pregnancy Association say that your breasts may become sore when implantation happens. In fact, your breasts may appear swollen and tender even as early as 1 to 2 weeks after conception. 11
Other signs of implantation or early pregnancy that you might notice before a pregnancy test tests positive are frequent urination, food aversions or cravings, backaches and headaches, and mood swings.
If you notice these signs of pregnancy, and you know that you had intercourse around the time of ovulation, you should take a home pregnancy test. If the results are negative, they may become positive several days later as pregnancy hormone (hCG) increases.
10 Simple Steps To Do Accurate Urine Pregnancy Test At Home
What is one of the most annoying things to do during pregnancy? Yes, it is the urine test. You have to get it done so many times during the nine months that you begin dreading it. But if you understand the usefulness of a urine test during pregnancy, you wouldnвЂ™t mind it at all. Right from your home pregnancy test to the tests that confirm anomalies, you need a urine test for several purposes during your gestation.
MomJunction explains about the various urine tests that you have to take during pregnancy and how they are useful for you and the baby in the womb.
What Is Urine Home Pregnancy Test?
During pregnancy, your placenta produces the human chorionic gonadotropin (hCG) hormone, which appears in the urine and blood about ten days after your last period. This is the time when the fertilized egg implants in the uterus (1). The home pregnancy test detects the presence of hCG in urine.
In the initial eight to ten weeks, hCG levels increase rapidly. They reach the peak during the tenth week and then decline until the end of your pregnancy (2).
What Does Urine Test Show?
The urine test confirms pregnancy if you take it around one to two weeks after missed periods. It helps you know whether or not hCG is present in the urine. It is a qualitative test and does not give you the quantity of the hormone present in your body. The presence of hCG is a positive sign of pregnancy.
Steps To Follow For An Accurate Urine Test To Confirm Pregnancy:
Follow these simple steps while doing a HPT to ensure the accuracy of urine pregnancy test.
1. Know when to take the test:
Wait for about one to two weeks after you miss your period to get the best results. You may tend to miscalculate when your period is due in the case of irregular periods, and this can affect the test. In fact, out of every 100 pregnant women, 10 to 20 will not be able to detect their pregnancy on the first day of their missed period due to miscalculated periods (3).
2. Check the expiration date:
If you are planning to take a home pregnancy urine test, check for the expiry date, because the newer the pregnancy kit, the better the results. Also check for the condition of the kit packaging (the open seal, В wearВ and tear, etc.).
If you have stocked up a pregnancy kit from months ago, do not use it.
3. Test in the morning:
Going for a morning urine pregnancy testВ (first urine in the morning) helps you get the most accurate results because your urine is concentrated in the morning with the highest levels of hCG. Do not drink fluids before collecting the urine as it can dilute the hCG levels and alter the results.
4. Collecting the urine sample:
Some home pregnancy kits require you to hold an indicator stick under the urine stream until it soaks completely. This will take about three to five seconds. Some other urine testing kits will require the urine sample to be collected in a cup and test a few drops on the stick.
5. Read the instructions carefully:
Before taking the test, go through the instructions given in the overleaf. Different brands have different specifications, and you need to understand the one you are about to use.
Factors such as the method of collecting the urine, the length of the time you need to let the urine stay on the test stick and the symbols used to prove the results could be different for each brand.
6. Familiarize yourself with the symbols:
You have to know the symbols listed on your pack to understand the reading better. If you are unable to decipher the symbols when reading the results, do not panic. Call the toll free number listed on the pack to seek help.
7. Prepare yourself mentally:
Testing for pregnancy involves mixed feelings. If you are a first timer, you are likely to be nervous and jittery. Prepare yourself mentally before taking the test. Talk to your partner and close friends for support and to come out of your fears. Do not worry about the result. Understand that pregnancy is a natural process.
8. Do the test methodically:
Even though a urine test may look like a walk in the park, you follow all the instructions systematically. Begin with reading the instructions, know how to collect the urine sample, and then test it.
9. Wait for the results:
After the test, place the strip horizontally on a clean surface for the readings. Different tests have different time requirements. The waiting time is usually anywhere from one to five minutes but some tests are said to take as long as ten minutes to give the correct result.
Some women panic and keep staring at the strip nervously, waiting for the result. Remember that it will not improve the results. Instead, take a break and set a timer.
Dispose of the strip after the result is out. Do not consider the result if it takes too long to come out. The results may be inaccurate and can give a false positive evaporation line.
10. Checking the final result:
Once the waiting time has elapsed, check for the results. While the symbols vary with brands, the second line appearing on the stick indicates a positiveВ result.
- If you see even a faint line appearing next to the first one, consider that as a positive. This indicates that the test had picked up traces of hCG in your urine.
- If you are not sure about the line, which is too light and not definitive, wait until the following morning for a retest.
Things To Do After The Results:
Reading the results can be a life changing moment for you. However, this is just the beginning. Make sure you know what to do next after doing the urine test.
Here are some things you need to keep in mind:
1. In the case of a positive result:
If a urine pregnancy test result is positive, make an appointment with your doctor. Your specialist may also recommend a blood test to confirm the results of the urine test. In most cases, the results of a urine test are accurate.
2. In the case of a negative result:
If you have missed your period and still the result shows negative, wait for some more time and take the test again. False negatives are sometimes possible. These can happen when you have miscalculated your ovulation date or taken the test earlier than recommended.
How Accurate Are Home Pregnancy Tests?
Home pregnancy tests claim to be 97% to 99% accurate if they are done in the right way (4). However, in certain cases, as discussed below, the result could be false positive or false negative.
If you continue to get false results in spite of the symptoms of pregnancy such as missed period, nausea, fatigue and breast tenderness, wait to take another test or check with your doctor.
Reasons For A False Positive:
Although false positives are rare after a urine test they are not ruled out. A false positive result is nothing but the test proving that you are pregnant, while in reality, you are not.
Here are some reasons for the false positive result of a urine test. However, the reasons could vary from one woman to another.
1. Chemical pregnancy:
Also known as an early miscarriage, this is a scenario where you could have become pregnant but have lost it shortly after the implantation (fertilized egg settling in the uterus).
2. Missed reaction time:
Reading the results after the recommended time has elapsed can give you a wrong result. Your stick has surpassed the actual reaction time, and there is every chance for it to show a false positive.
If you are undergoing any medical treatments for fertility, which involves a trigger shot of hCG, make sure there was enough time for the shot to metabolize and clear your system. Usually, fertility experts suggest that you should wait for about 14 days to clear the impact of the hCG shot before taking a pregnancy test.
4. Evaporation line:
This is a deceptive line that comes on the stick in a different color. It looks very similar to the positive line. The test kit indicates a certain color for the positive result, and the test is positive only if the line appears in that color.
Just like a false positive, the test result can be false negative as well.
Reasons For A False Negative:
If the test indicates a negative again and again, do not worry. False negatives are common. See a doctor to find out the reason for your missed period.
False negatives can happen due to several reasons, some of which are listed below (5):
1. Testing too early:
If you undertake a pregnancy test in a sheer rush of anxiety, be prepared for a false negative. You have to wait until it is time to take the test. The chances of getting a false negative are high if you take the test immediately after missing your period.
2. Low sensitivity of the strip:
Despite picking the latest pregnancy kit, there is every chance of your strip being less sensitive while detecting the level of hCG due to a manufacturing defect. If you are not convinced with the negative result, try and retake the test with a different brand of home pregnancy kit.
3. Diluted urine:
This is the very reason why you should take the test early in the morning. If it is taken at other times of the day, the diluted urine might give a misleading result. Sometimes, your early morning urine could also be diluted. In that case, take the test again on the next day. The results could be different.
Even if the test is negative, we suggest you to be positive and have a word with your doctor (6).
Once your pregnancy is confirmed, you will have to undergo urine tests at various times during the nine months. This time it will not be at home but a clinic or lab.
Clinical Urine Test (Urinalysis) At DoctorвЂ™s Clinic:
Your doctor will recommend a urine test during the first prenatal care visit to confirm the result of the home test and also to rule out any health issues that could pose a danger to your pregnancy. You will continue to have periodic tests during the prenatal appointments (7).
Why is the clinical urine test done?
A urinalysis is usually performed to:
What does a urine test involve?
Urine tests during pregnancy are evaluated in three ways вЂ“ visual examination, dipstick test and microscopic exam (8).
Initially, the pathologist or the lab technician will examine the appearance of your urine. If it is clear, cloudy, has an unusual odor, etc. Unusual color or odor could indicate an infection. Sometimes, the food you eat may also make your blood look different. For instance, beets or rhubarb give a red hue to your urine.
Chemically prepared thin plastic strips known as dipsticks are used to detect abnormalities. They are dipped in your urine sample to screen for some indicators.
- PH (acidity) indicates the acid content in the urine. Abnormal levels detect a urinary tract or kidney disorder.
- Concentration and number of particles dissolved in it. Higher concentrations are a result of not taking enough fluids.
- Sugar quantity in the urine. High levels indicate gestational diabetes.
- Protein levels in urine are usually low. Higher levels are a sign of urinary tract infections and kidney issues. In later pregnancy stages, it can be a sign of preeclampsia associated with high blood pressure.
- If Ketones are detected in the urine (which happens when stored fats break down for energy), it indicates diabetes accompanied by weight loss, nausea, and vomiting.
- Bilirubin is produced as a result of the breakdown of red blood cells. It is usually present in the blood, passes through the liver and then becomes a part of the bile. If it is present in urine, it indicates liver disease or damage.
- If White blood cell products such as nitrites or leukocyte esterase are detected in urine, it is an indication of urinary tract infections (UTI).
- Blood in the urine may be a sign of kidney or bladder infections, stones, cancers or other blood disorders.
Some drops are observed under a microscope to check for the following:
- Red blood cells (erythrocytes) вЂ“ sign of blood disorder, kidney disease or bladder cancers
- White blood cells (leukocytes) вЂ“ sign of infection
- Casts вЂ“ tube-shaped proteins which form due to kidney disorders
- Bacteria or yeasts вЂ“ signs of infection
- Crystals вЂ“a result of chemicals present in urine, and indicate kidney stones
The urine test at the clinic will not always diagnose a problem. Sometimes, follow-up tests are required to detect the condition.
Urine Culture Test During Pregnancy:
Urine culture is a part of the prenatal examination to detect any bacterial infections that have been existing without symptoms.
Women are prone to urinary infections since their urethra is shorter than males and is closer to the anus. This allows transfer of bacteria from the anal region into the urethra and from there to the urinary tract. You also can get UTI if your partner has it.
Urine culture helps the doctor identify the bacteria and prescribe the right antibiotics. If the culture returns negative, it means your urine is infection-free and hence, you donвЂ™t require antibiotics.
A healthy pregnant womanвЂ™s urine is sterile and doesnвЂ™t contain fungi, bacteria or any other microorganismsВ (9).
Why Does The Doctor Recommend Urine Culture?
Your OB/GYN will ask for a urine culture to:
- Detect the UTI-causing bacteria.
- Prescribe the right antibiotic through a test called sensitivity testing.
- Find out whether the treatment helped the UTI to clear up completely.
You will have to give a urine sample twice for urine culture. Once to detect the bacteria and later to make sure the infection has cleared up and posed no risk to you or your baby.
Preparing For A Urine Culture:
You donвЂ™t have to do anything to prepare for a urine culture. But inform your doctor about the antibiotics that you are currently taking or have just taken.
Usually, the first urine of the day is the best for urine culture, as it will contain high levels of the infection-causing bacteria. Therefore, try not to ease yourself before you give a sample.
Collect the urine midstream.
Collecting Urine Sample:
- Wash your hands before you take the urine sample. This prevents cross-contamination.
- Then clean your vaginal region with a tissue paper to remove any contaminants. Use a front-to-back motion to clean the area.
- Let the urine initially flow into the toilet and then hold the sample cupВ midstream.
- You may hold the folds of the skin apart while urinating to minimize the chances of contamination.
- Replace the lid after filling the plastic container.
- Wipe the outside of the container well and transfer it to your refrigerator. You can store the urine sample for up to 24 hours before taking it to the lab for analysis.
- Follow the labвЂ™s instruction on when and how to bring the urine sample for urine culture.
If you are worried about urine culture, talk to your healthcare practitioner and clear your doubts and worries. Understand the risks of UTI during pregnancy and the treatment. The more you know, the easier it will be to deal with your situation.
Results Of A Urine Culture:
Since the laboratory has to grow the organisms present in the urine, it takes about one to three days to get the results. Some of the microorganisms take longer than three days to grow in a lab setting. Hence, it could also be a week before you get the complete results.
The report will state the following:
Negative:В This means no bacterium or fungus grew in the culture. You will not require treatment.
Positive:В If bacteria or fungi grow in the urine culture, the result will be positive. Usually, if the bacteria count is 100,000 or more per milliliter, it means you have an infection. However, if the bacteria count is from 100 to 100,000, it could be an infection or contamination of the urine sample. You will be asked to give another urine sample so that the culture can be repeated. If the count is 100 or less, infection is ruled out. This is also the result you should expect if the doctor puts you on antibiotics and asks for a second urine culture.
Your test results can be affected due to several reasons, including:
- You are currently taking antibiotics.
- You have just finished a course of antibiotics.
- You are taking diuretics, which dilute the urine sample. This reduces the number of bacteria present in the sample.
- You are consuming a lot of vitamin C.
Urine tests are the first tests we usually take during pregnancy. And now you know the different types of urine tests and why they are to be taken. Knowing about the importance of urine tests will clear the air and make it less embarrassing for you. Do not panic if you are diagnosed with any infection as your practitioner will help you with a treatment plan.
Have an experience to share or questions to ask about urine pregnancy tests? Let us know in the comment section below.
Http://www. pregnancy-baby-care. com/pregnancy-test/urine-pregnancy-test. html
Http://www. babymed. com/pregnancy-test/when-does-the-urine-home-pregnancy-test-hpt-become-positive
Http://www. healthyandnaturalworld. com/how-long-after-implantation-can-i-test-for-pregnancy/
Http://www. momjunction. com/articles/simple-steps-accurate-urine-test-pregnancy_0075435/