Dr. Aruna Ashok MBBS, MS OG, DNB OG
- Clinical Director
Aruna Ashok | 22 September 2025
Women, in general, have a strong desire to find out about their pregnancy as soon as possible.
During the first trimester, their bodies undergo tremendous changes. One of the significant changes is an increase in hormone levels, which are passed out through urine. Human chorionic gonadotropin (hCG) is one such hormone that increases its levels soon after implantation happens by the fertilised egg within the uterus.
Pregnancy tests are used to determine the existence of the hCG hormone in the woman’s body either through bloodstream or urine. Studies show that pregnancy tests show accurate results, typically anywhere between 97 and 99 % in recognising pregnancy by identifying hCG hormone. These tests are frequently performed to confirm the pregnancy as early as possible. This is because the implantation process usually begins only between 6- and 12-days following ovulation. Therefore, it requires at least two days for the hCG hormone to be detected in the pregnancy tests.
Allowing enough time for the hCG hormone to rise to its level can exhibit the most accurate results.
This blog can help couples who wonder, “After implantation, when will a pregnancy test be positive?”. So, why wait? Keep reading to learn more about pregnancy tests.
Let’s start with ovulation.
Ovulation usually occurs in the mid-cycle, that is, between the 14th and 15th day of a 28-day menstrual cycle. Ovulation is the reproductive process that ruptures and releases the most fertile egg from the ovary. Soon after its release, it reaches the uterus through the fallopian tubes. On its way towards the uterus, the ruptured egg and sperm may become fertilised. Note that all these things happen in the fallopian tubes.
Once fertilised, the single-celled zygote multiplies by doing rapid cell division while reaching the uterus. This may take about 6 to 10 days to travel from the fallopian tube and then to the uterus. After reaching, it finds the suitable spot within the uterine lining (uterus) and implants in it for further development.
While doing so, it may disturb the surrounding tiny blood vessels within the uterus. This disturbance has a higher possibility of causing minor uterine bleeding. Some women may experience implantation bleeding because of this.
As soon as implantation takes place, your body starts to produce hCG hormone from the embryo, especially in the early stages of development. Noticeable traces of hCG can be observed at least 14 days after your ovulation. As days progress, the formation of the placenta happens, which then takes over hCG production. The placenta eventually increases the production of the hCG hormone as pregnancy develops.
It is important to understand that pregnancy cannot be confirmed only with symptoms. Its symptoms may widely change from individual to individual. Some women may experience the implantation symptoms right away. While others take time to exhibit the symptom in their later stages of pregnancy.
Implantation symptoms are basically influenced by the hormone fluctuations. However, the common symptoms may include:
Women may do a pregnancy test after noticing that their period is due. They may also choose to do a test at least 3 to 7 days after having implantation bleeding. Studies show that around one-third of women notice implantation bleeding. It may typically happen around their expected menstrual cycle. Because of this, many women misunderstand implantation bleeding for PMS (premenstrual syndrome).
Soon after implantation, the hCG levels generally begin to rise. If you prefer to do at-home urine tests, you may need to wait for 7-10 days following implantation to confirm your pregnancy. On the other hand, if you prefer to do blood tests, you may need to wait only for 3-4 days. Both of these tests require this much of a specified timeframe to allow the hCG hormone to reach a detectable level. Doing the pregnancy test earlier than this timeframe may exhibit false negatives, even if you are pregnant.
There are two major types of pregnancy tests to confirm whether implantation has successfully happened or not. One is a blood pregnancy test, and the other is a home pregnancy test. Both of these tests identify the pregnancy by determining the hCG hormone.
Note that hCG hormone levels don’t rise unless the implantation takes place. hCG hormone is otherwise referred to as the pregnancy hormone.
Blood tests can recognise the spiking levels of hCG hormone in pregnant women as early as 6 to 8 days of the ovulation period (or 3-4 days after implantation). This is possible only if fertilisation has happened within this timeframe. Furthermore, a blood test can be done to confirm the pregnancy at any time of the day.
Blood pregnancy tests work by determining the hCG hormone in the woman’s bloodstream. The blood for this purpose is often drawn from your veins in the arm.
The blood pregnancy test results can be exhibited in two ways: qualitative and quantitative.
Unlike blood tests, urine tests can detect hCG hormone in pregnant women only after 10 to 15 days of their ovulation period (or 7 - 10 days after implantation). This is because the hCG hormone takes time to reach a detectable level in the urine. Furthermore, testing pregnancy using your first urine of the day (morning urine) can provide the most accurate results.
Many couples prefer using home tests as it is simple to use and cost-effective as well.
At-home pregnancy tests are purposely designed to determine the hCG hormone in the urine of women. Experts advise using the morning urine (first urine of the day) to achieve reliable results. This is because of the increased concentration of the hCG hormone in the sample.
Note that at-home urine tests are a convenient method to confirm pregnancy at home. Before starting to do it, read the instructions carefully. Some products indicate the results with a simple yes or no, and pregnant or non-pregnant, whereas others indicate the results with just lines. Likewise, read the instructions to know whether:
In whatever ways the product is designed, it contains antibodies to detect the hormone in your urine. The presence of hCG in the sample may bind with these antibodies and trigger a visual change. The change may include:
Having unprotected intercourse around the ovulation days can increase the chances of fertilisation of the released egg with the sperm. But then, the implantation of the fertilised egg within the uterus may significantly vary due to numerous factors like the uterine lining, conditions like endometriosis, and autoimmune disorders. Even though implantation generally takes place between 6 and 12 days of ovulation, these factors can sometimes lead to implantation failure. Even if the implantation is successful, several reasons can affect the pregnancy results.
There are two main types of inaccurate pregnancy results. They are:
It can be frustrating when it comes to experiencing implantation symptoms, but waiting for the specific timeframe to take a pregnancy test. No matter how much you emphasise those moments, you have to be patient to identify the result.
Pregnancy tests can give you a heads-up on what's happening inside your body. Depending on your childbearing plans, you can make the most informed decisions. You may visit the healthcare provider as soon as you get the positive results. They may start your prenatal care early for the betterment of the child’s development or make quick decisions.
1. Can a beta hCG test detect complications in the developing baby?
The answer to the question is yes. A quantitative beta hCG test can exhibit potential complications in the developing baby. But it cannot diagnose the exact complication like ectopic pregnancies, chromosomal abnormalities, and miscarriages. Rather, the condition is determined by further investigations and ultrasounds. Your healthcare provider may suspect the abnormalities if the hCG levels are either too high or too low in the recurring pregnancy results.
2. What is the correct time to perform a pregnancy test?
The optimal time to do an at-home pregnancy test is after missing your period. Waiting a few days more after your missed period can minimise the chances of false negatives or false positives. This allows sufficient time for the pregnancy hormone (hCG) to rise and show reliable results.
3. Are traditional home pregnancy tests reliable?
Traditional home pregnancy tests are generally not reliable. This is because of its lack of scientific evidence. However, people from different cultures still use household items like sugar, salt, and vinegar to detect their pregnancy. Using modern medical methods to detect hCG hormone (human chorionic gonadotropin) in either blood or urine is more reliable and accurate to confirm the pregnancy.
4. Can a negative result change to a positive result?
The answer to the question is yes. There are possibilities that a negative result can turn into a positive after some time due to various reasons. They may include taking a test too early, using an expired package, or using diluted urine. Taking the test a few days later may allow the hCG hormone to rise rapidly and produce a positive result.
5. When will a pregnancy test be positive?
A pregnancy test will exhibit a positive result when your body produces sufficient hCG (human chorionic gonadotropin), which is then evident in urine and bloodstream. The levels of hCG may increase to a detectable level typically after a missed period. Taking a pregnancy test during this time may exhibit the most reliable results.
