The Sensitivity Of The Pregnancy Test
Different pregnancy tests have different sensitivities and that has an impact on how early can pregnancy be detected. The lower the sensitivity, the earlier a pregnancy test becomes positive. Sensitivities are indicated in mIU/mL, the lowest amount of hCG in the urine that tests positive. A sensitivity of 20 mIU/mL requires one-half the hCG level to be positive when compared with a 40 mIU/mL sensitivity level, and it may become positive several days earlier than the pregnancy test with a higher sensitivity. Make sure you read the package of the pregnancy test to determine your pregnancy test’s sensitivity.
How Does A Pregnancy Test Work
All pregnancy tests detect the hormone human chorionic gonadotrophin , which starts to be produced around 6 days after fertilisation.
Most pregnancy tests come in a box that contains 1 or 2 long sticks. You pee on the stick and the result appears on the stick after a few minutes. All tests are slightly different, so always check the instructions.
Calculate Using A Pregnancy Test With Weeks Indicator
All pregnancy tests are designed to detect the pregnancy hormone human chorionic gonadotropin in urine, but some pricier tests offer a weeks indicator that promises to tell how far along you are. Unfortunately, these tests are pretty vague, stating only one to two weeks, two to three weeks or three-plus weeks pregnant. In addition, the tests measure from implantation, not from your LMP. A test might say that youre one to two weeks pregnant but youre actually four weeks pregnant, according to standard pregnancy calculations.
When Is The Best Time To Take A Pregnancy Test
Ovulation generally occurs around day 15 of a 28-day cycle. In a normal pregnancy, an egg is fertilized in the fallopian tube and then travels into the uterus, where it implants itself in the uterine wall. A womans body begins to produce hCG from cells in the developing placenta soon after implantation of a fertilized egg inside the uterus. Around eight days after ovulation, trace levels of hCG can be detected from an early pregnancy. That means a woman could get positive results several days before she expects her period to start.
The tricky part of timing when to take a test is that the duration of the first half of a menstrual cycle is more variable than the second. The length of time from the first day of a period to ovulation can vary by several days from month to month. Sexual activity around ovulation leads to the possibility of fertilization of the released egg by sperm. But even then, the time frame for a fertilized egg to implant can vary. And hCG isnt produced until after implantation has occurred.
For the most accurate results, we recommend that women test in the morning on the day they expect their period to start. This allows for variability in the timing of ovulation, fertilization, and implantation. Testing in the morning provides a urine sample that is concentrated.
I Had Sex Two Weeks Ago But My Doctor Says That Im Four Weeks Pregnant How
88 things nobody tells you about being pregnantIf you have a standard 28-day period, you will likely ovulate around day 14 and are most fertile around days 12, 13 and 14when you had sex to conceive. It takes about nine days after ovulation for implantation to occur, which brings you to around day 23. It takes a few days for your pregnancy hormone levels to be detectable by a pregnancy test, bringing you to around day 28. How far along you are in your pregnancy isnt calculated from conception or implantation but from the first day of your last normal period. If you had your period four weeks ago, then ovulated and had sex two weeks ago to become pregnant, youre currently four weeks pregnant.
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How Early Can Home Pregnancy Tests Show Positive Results
In the Aerosmith song Sweet Emotion, Steven Tylers lyric the rabbit done died refers to the original way a pregnancy test was performed one that literally killed rabbits. Urine from a woman who thought she might be pregnant was injected into a rabbit, which would then be surgically opened so its ovaries could be inspected. If the woman was pregnant, the rabbits ovaries would undergo noticeable changes due to the hormone human chorionic gonadotropin that develops early in gestation. The rabbit unfortunately didnt survive.
Thankfully, pregnancy tests have evolved substantially since the 20th century. Women now have access to advanced tests that can detect a pregnancy days before a missed period. In fact, a CBS News article outlined the best home pregnancy tests according to research from Consumer Reports, based on ease of use, ease of reading results, and effectiveness. Many tests today are marketed as simple and effective, but getting accurate results comes down to when the test is taken.
My Clearblue Pregnancy Test With Weeks Indicator Says Im Not Pregnant What Should I Do
You may not be pregnant, or the level of pregnancy hormone may not yet be high enough to be detected, or you may have miscalculated the day of your expected period.
- If you tested early, test again when your period is due.
- If your period is overdue, test again in 3 days time. If this test gives you a ‘Not Pregnant’ result and you still have not had your period, see your doctor.
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When A Blood Test Is Used
In routine pregnancies with healthy women, at-home urine tests are more than sufficient and effective. Blood tests are primarily used in doctors’ offices, specifically, if there is a potential issue with the pregnancy or some other complicating factor , in which the greater sensitivity of the blood test is needed.
Blood tests may be ordered for higher risk pregnancies, during fertility treatments, when urine tests read negative but a period hasn’t come, to confirm or rule out a possible miscarriage or multiples, and to diagnose a potential ectopic or tubal pregnancy, as well as due to other pregnancy complications.
How Pregnancy Tests Work
Pregnancy tests are able to detect a hormone called human chorionic gonadotropin, or HCG. This hormone is produced during the early stages of pregnancy. But understanding that hormone, how pregnancy tests work, and how soon a pregnancy test will read positive may require going back to the basicsthe basics of the birds and the bees that is.
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How To Use Pregnancy Tests
A person might have a pregnancy test in a clinic or doctors office. Depending on the test, this involves giving either a urine or blood sample. Healthcare professionals may test this immediately or send it to a laboratory for testing. The lab usually takes a day or two to return the results.
Home pregnancy tests are simple to use, but it is crucial to follow the instructions carefully. In general, they involve:
- urinating directly onto the testing stick
- urinating into a clean cup, then dipping the testing stick into this for a specified amount of time
- urinating into a clean cup, then using a dropper to apply urine to an area of the testing stick
A persons hCG levels change rapidly throughout pregnancy. It is often best to take a pregnancy test
Many home pregnancy tests claim to be accurate up to 99% of the time. A positive result is typically correct. A negative result is more likely to be incorrect.
However, these accuracy claims assume that the person has used the test correctly.
Most tests can produce accurate results on the first day after a missed period, but to ensure accuracy, it is advisable to start testing 1 week after a missed period.
For around of pregnant people, a home pregnancy test does not accurately detect the pregnancy on the first day of their missed period. This might result from a person having irregular periods or miscalculating when their period was due.
But various other factors can influence the accuracy of pregnancy tests, including:
Factors That Cause A False Negative
Can you get a false negative pregnancy test? Absolutely. But you can decrease your risk of getting a false negative by keeping an eye out for the variables that cause a negative pregnancy test result, such as:
- Urine concentration The more diluted your urine, the harder it is for a pregnancy test to detect accurate amounts of HCG . Instead, try to take your pregnancy test first thing in the morning when the chemicals in your urine are at their most concentrated.
- Testing too early If youre trying to get pregnant, you may be meticulously tracking your menstrual cycles so you can pinpoint your most fertile periods. But not every woman operates on a 28-day cycle. If you get a negative test result, you might have caught your egg right at implantation, before HCG levels are high enough to be detected. Try waiting a few days and test again to ensure an accurate reading.
- Delayed implantation Typically, a fertilized egg will mosey down into the uterus for implantation 6-9 days after fertilization. But thats not always the case for every woman. In fact, for 10 percent of pregnant women, the embryo doesnt implant until the first day of your missed period. And remember, HCG isnt produced until implantation, so you may not get a positive pregnancy test until week 6 or 8 of your pregnancy!
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When Youre Positively Pregnant Find More Answers With Sneakpeek
When that test strip finally tells you the good news, you may feel completely overjoyedthen overwhelmed with more questions. One of the biggest questions in a parents mind after a positive pregnancy test? Am I having a little boy or a little girl?
You wont have to wait long to find out with a little help from the SneakPeek Early Gender DNA Test. At 99.9% accurate, this gender prediction test can tell you whether youre having a boy or a girl as early as eight weeks into pregnancy.
Even better? There are no vague test strip results to interpret, no sticks to pee onjust answers. Find yours with the SneakPeek Early Gender DNA Test!
This post has been reviewed for accuracy by the following medical professional:
Katie Phillips, MSN, CNM, APRN
Nurse midwife and mom to 5 kiddos ranging in age from 7-20 and a chocolate lab. I own my own birthing center, which is the first and only one in Bay County, Florida. I love the beach, swimming, horseback riding, and reading.
How Many Weeks Pregnant Am I
Calculating your baby’s due date isnt as easy as you might think. Heres how to figure out how many weeks pregnant you are.
OK, How many weeks pregnant am I may seem like a funny thing to ask Dr. Google, but its pretty common to be a little confused about your due dateor how many weeks pregnant you arein the earliest stages of pregnancy. Thats true even if youve been tracking your cycles religiously, and even if you suspect you know the exact date of conception.
Heres why: Pregnancy is actually measured from the first day of your last menstrual periodbefore youve finished bleeding, before youve ovulated and before youve engaged in any, um, baby-making activity.
Youre having a babysubscribe to our Todays Parent Pregnancy by Week newsletter!Many women dont even bother taking a pregnancy test until theyve ovulated, had sex, and missed a period. Home pregnancy tests will not work until youre at least 5-6 days away from the expected date of your next period, anyway.
Because most womens menstrual cycles are around 28 days or four weeks long, some couples who are trying to conceive refer to the time between ovulation and being able to take a pregnancy test as the two week waitor TWW, in message-board acronyms.
Heres an example: if you just got a positive result on a home pregnancy test and suspect you likely ovulated and conceived about two weeks ago, your medical providers already consider you to be four weeks pregnant.
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When Do You Start Showing
You ll probably start to show in pregnancy at 12 to 16 weeks. You re more likely to show early if you re short, carrying multiple babies, or you ve been pregnant before. By week 20, your doctor will start measuring your fundal length, the distance between the pubic bone and the top of the uterus.
Next Steps After A Positive Test
After getting a positive test result, youll need to do a few things in order to support a healthy pregnancy:
- Contact your doctor or healthcare provider for an initial appointment. You may have to wait several weeks for your appointment, so it is best to schedule one as soon as possible.
- Discontinue alcohol and drug usage when you get a positive pregnancy test result. Also, consider limiting your caffeine intake while you are pregnant.
- Begin taking prenatal vitamins. Choose one that contains folic acid, which may prevent birth defects. Its important to take these vitamins early in order for them to be in your system before you are further along in your pregnancy.
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Early Result Pregnancy Tests
Some pregnancy test kits boast early results that promise an answer three or four days before your missed period. These tests assume a 14-day luteal phase, which is the time between ovulation and when you get your period. The problem is that you may have a shorter or longer luteal phase.
If your luteal phase is usually 12 days, four days before your missed period would be nine days after ovulation. Thats way too early to test. For you, taking the test four days before your missed period would be pointless.
If you have a luteal phase of 15 days, four days before your missed period is 12 days after ovulation. You still may not have enough hormones that early. However, you have a better chance than someone with a shorter luteal phase.
If youre having fertility treatments and you have had an hCG trigger shot, then you should not take an early pregnancy test. An early test may detect the remains of fertility medication.
Weeks Pregnant: The 4th Week Of Your Pregnancy
Congratulations! Pregnancy weeks four through seven are when most women discover they are pregnant. This week-by-week newsletter will keep you informed about what to expect during your pregnancy. If you have just found out that you are pregnant, you may want to begin by reading weeks 1 through 3. Get the Fetal Life App for Apple and Android endorsed by the American Pregnancy Association.
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Best Time Of Day To Test
Youre more likely to get an accurate result if you take the test in the morning. This is especially true if your period is not yet late, or if your period is only a couple of days late.
Your urine is usually more concentrated when you first wake up. This generally means that the amount of hCG is a bit higher, and youre more likely to get a positive result if youre pregnant.
However, you can still take a pregnancy test at a different time of day. Youre just more likely to get a false negative, especially if youve been drinking a lot of water and your urine is diluted.
How Can I Tell How Far Along I Am Without Knowing My Last Period
What if I dont know the date of my last menstrual period?
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If Pregnancy Test Says Positive Then How Far Along Can You Be
Well a pregnancy test can detect hCG levelsas far as 5 days before your expected period. Though it is notparticularly accurate. I personally recommend taking the test 1-2days before your expected period for best accuracy. A pregnacnytest cannot really tell you how far a long you are. If you thinkyou may be pregnant, and possibly have been for a little while youcould have suspected your implantation bleeding for you period. To know how far along you are you should contact your OB/GYN. Here is a link to awebsite that will calculate the probability of your pregnancy:http://www.thepregnancytest.com/
What Should I Do After Getting A Positive Pregnancy Test
If you take a pregnancy test at home and its positive, there are a few things you should do, including:
- Take your prenatal vitamins pick a vitamin with folic acid included in the ingredient list. Its recommended that you actually start taking these vitamins before becoming pregnant. This is because the folic acid can help prevent birth defects.
- Make sure to pursue healthy habits. Its recommended that you dont drink alcohol or smoke during pregnancy. You may also want to limit the amount of caffeine you consume each day during pregnancy.
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When Should I See A Doctor For A Clinical Pregnancy Test
Most women who have a positive pregnancy test should wait a week or two before calling the Ob/Gyn office for a pregnancy blood test. We suggest waiting because the rate of early pregnancy loss is high, and its possible that it might have been a chemical pregnancy.
However, women with a history of ectopic pregnancy or current abdominal pain should call the doctor right away to be examined. Ectopic pregnancies implant outside of the uterus and produce hCG, resulting in positive pregnancy tests. However, these pregnancies can cause abdominal bleeding and prompt medical care is necessary. Women who have congenital heart defects or other chronic physical or mental health conditions should also see a doctor right away because treatment plans or medications might need to be altered to protect the woman and the fetus.
Advances in home pregnancy tests give women greater insight into whats going on in their bodies sooner than ever before. No matter what a womans childbearing plans might be, its essential to get quick, accurate results at home so she can plan her next steps accordingly.