The human body is complicated, and its working mechanism is even more complex. It's difficult to understand the number of chemical processes taking place inside the body. While changes on the outer body are mostly visible, those taking place inside it cannot be seen.
Pregnancy Test: Focus Areas
- The best time to take a pregnancy test
- The first positive pregnancy test in women
- Irregular periods and test for pregnancy
- Testing pregnancy while using pills
- Pregnancy test after discontinuation of pills
- IVF treatment and home test for pregnancy
- Testing pregnancy after abortion/miscarriage
In some cases, symptoms are noticed, whereas in others, different tests have to be performed for detecting such changes. Pregnancy is one such condition, wherein, the symptoms may or may not appear right after conception. During this period, most women are found to be confused about whether they are pregnant or not.
There are various factors that affect the accuracy of home pregnancy test (HPT). When the test is done, the sensitivity of the test, the type of test,etc., are some of these factors. Here is a brief overview about the best time to take a home pregnancy test. Before starting with the subject, let us a look at the mode of working of these tests.
Types of Pregnancy Tests - How They Work?
The most common types of tests for pregnancy are blood tests and urine tests. While a blood test to detect pregnancy is done in the doctor's clinic, urine test can be done at home too. There are two types of pregnancy blood tests. The qualitative hCG test detects the presence of the hormone, but the quantitative one detects its amount too.
Though the methods are different, the working mechanism of both blood and urine tests for pregnancy is the same. These tests are used to detect the presence of the hormone human chorionic gonadotropin (hCG) in the sample. This hormone, which is also known as pregnancy hormone, is released by the growing placenta and is found in pregnant woman.
As the hormone is released by the placenta, these tests work only after the fertilized ovum gets implanted in the uterus and develops placenta. So, hCG levels may not be in detectable levels (for HPT), right after conception.
Once the placenta starts growing during the early pregnancy, hCG level rises quite fast (doubles every day). A higher level of hCG gets detected easily. Therefore, as the pregnancy progresses, the accuracy of the result increases. Now that you have a basic idea about these tests, let us take a look at your doubts regarding home test for pregnancy.
When to Take a Pregnancy Test? - General FAQs
I have normal cycles. When is the best time to take a pregnancy test?
The very first indication of pregnancy is the delay in menstruation. Though, menstruation can be delayed with other factors too, the first and foremost indication of pregnancy is missed periods.
Some women may experience implantation bleeding too. This mild bleeding may happen when the fertilized ovum attaches to the uterus. However, this may not occur in most women and others may not notice it. So, missed periods is considered the first sign of pregnancy.
Medical practitioners perform a blood test for detection. You can also opt for one at home. The test taken with the very first morning urine gives the most accurate result. If the test is negative on the due date, repeat it after two to three days.
Why did I face a delay in getting a positive pregnancy test?
For a pregnancy test to come positive, the placenta must be formed. This happens only after the fertilized egg implants itself on the wall of the uterus. Such implantation may occur anywhere between 6 to 12 days from the date of fertilization.
Fertilization may happen within two days of ovulation, if sperms are present at that time. As sperms can live for around seven days inside the female body, unprotected sex within seven days prior to the date of ovulation and one or two days after ovulation may result in pregnancy, if everything is normal.
But, the date of ovulation may not be the same for all. Thus, there are various factors that affect the detection of pregnancy at an early stage. They include the date of ovulation, the date of implantation and the growth of placenta. Even the sensitivity of the test matters. This is the reason why the time of first positive pregnancy test differ in women.
My periods are irregular. When should I take a pregnancy test?
In that case, you cannot calculate the exact date of ovulation and menstruation. This makes it difficult to judge the best time to take a pregnancy test. You may wait for 15 to 20 days from the date of unprotected sex.
Another way out is to find out the longest cycle in the recent months and wait for that much days, before taking the test. If you get a negative test, wait for another two, three days, before repeating the test.
How soon to take a pregnancy test, if I am on the pill?
Those who are taking contraceptive pills may also get pregnant, if they do not use them properly. It may happen that you forget to take pills for a day or two. In some cases, certain medication are found to interfere with working of contraceptive pills.
These pills may get ineffective, if the user suffers from stomach upset for some time. In this case too, you can take a pregnancy test, after 20 days from the date of missed pills/stomach upset/use of medication or unprotected sex. Even if the result is negative, repeat the test after three days.
I have stopped the pills recently. When to take a pregnancy test?
Those who have stopped pills have chances of getting pregnant. Here, the periods can be irregular and so, it is difficult to calculate the time of ovulation and menstruation. It is advisable to go for a pregnancy test, after 19 to 20 days from the date you stopped taking the pills. Repeat the test after three days, in case your first test comes negative.
How soon can I tell if I am pregnant after IVF?
In Vitro Fertilization (IVF) is one of the highly popular infertility treatment methods. In this method, the process of ovulation is controlled hormonally and the ovum is fertilized with the sperm in an artificial medium outside the womb. The embryo is then transferred to the uterus.
The woman who is undergoing this procedure, must take different types of medication and hormone injections. It has been noted that in case of IVF pregnancy, the production of hCG may get delayed, by some weeks. So, a home pregnancy kit may not detect such pregnancies (there are exceptions too), during the early stages.
It may also happen that the hormones introduced in the body (during the treatment) may produce signs and symptoms that mimic pregnancy. So, it is always better to wait for a day or two after the due date of menses, to take a pregnancy test at home. If the test is negative, repeat it after a few days and meet your doctor.
When to take a pregnancy test, if I had a recent abortion/miscarriage?
In this case too, it will be difficult to calculate the best time to take a pregnancy test. This is because of two reasons. Those with a recent abortion or miscarriage will have hCG in their body for at least nine weeks (from the date of miscarriage/abortion).
So, a positive result during this time may be due to the hCG levels from the previous pregnancy or the present one. Even after a month from the date of abortion or miscarriage, the periods may not be regular and in that case, it will be better to test pregnancy, 20 days after the date of unprotected sex.
If the abortion was done before two to three months, you may depend on home pregnancy kits. In case of a very recent abortion or miscarriage, consult your doctor, if you are doubtful of pregnancy.
Pregnancy Test Kit Sensitivity
Another factor that may affect the results of early pregnancy tests is the test sensitivity. Newly designed HPT kits are sensitive enough to detect even lower hCG concentrations and can provide a positive test quite early. The sensitivity of the HPT differs from kit to kit.
HPT kits detect hCG concentration in urine. Some show results with a concentration as low as 20 mIU per milliliter of urine, while some may need 150 mIU per milliliter of urine to give a result. Obviously, the former one is more sensitive. Usually, the sensitivity is written on the box of the kit. So the results can vary depending on the kit you have bought.
A highly sensitive test (can detect hCG in 20 mIU to 25 mIU) can detect pregnancies as early as 6 to 7 days from the ovulation date. But, there are chances that some of these pregnancies may not actually continue. In such cases, periods may follow a positive pregnancy test. So, it is always advised to test pregnancy on the due date of menses or after that.
For most of the HPT kits, the reliability varies from 95% to 99%. Actually, reliability depends on whether or not the test has been performed under 'optimum circumstances'. The instructions are available on the HPT kit box. Read and follow it carefully.
Make it a point to carry out this test with the first urine sample in the morning. If you test at any time during day, avoid drinking lots of water before it. Leave the kit once you have put urine into it. Check after the recommended time period. Do repeat the test after three to five days, just to confirm the result.