Should Pregnancy Test Lines Get Darker Week by Week?

Pregnancy test lines are the best indicator to understand the possibility of you being pregnant. When someone purchases a test kit and finds the test line gets darker, confusion arises then. The question is – should pregnancy test lines get darker?

Getting a pregnancy test line darker is a natural phenomenon. You may find thin, faint lines first, and the lines get darker after a few minutes. The hormone level during pregnancy doubles every 2-3 days. Due to the impact of hormones, the test lines get darker and more apparent. 

Pregnancy lines get darker gradually weeks after weeks. There will be mentionable dissimilarity in the darkness of lines between two weeks and six weeks. However, the lines might not be sufficiently dark when the hCG level is low. 

Should pregnancy test lines get darker be after weeks?

After several weeks, pregnancy test lines appear differently. If the hCG level is okay, your pregnancy test lines will be darker day after day. Here is the exact condition of pregnancy test line darkness at various weeks. 

Pregnancy test line week by week

Pregnancy test lines in the second week

How dark should a pregnancy test line be at 2 weeks? In the second week, pregnancy test lines might be faint or darker. Positive lines with the strong possibility of being pregnant may come at this stage.

Faint lines on your pregnancy testing kit indicate a presence of hCG in your body. That means you’re most probably pregnant.

Most people find extremely faint lines in the second week. Additionally, you can run the home pregnancy test with onion as a fun fact during pregnancy

However, faint pregnancy test lines may indicate false pregnancy sometimes. This situation is known as “chemical pregnancy.”

It occurs when a fertilized egg doesn’t grow properly. If the testing kit can detect low levels of hCG (around 10-15 mIU/L), then it’s reliable. In the second week, the hCG level remains near this range.

Third-week pregnancy test lines

The third week is one of the most important moments to be assured about pregnancy. Faint pregnancy lines are barely seen at this stage. After testing, approximately 5–50 mIU/ml or more can be found.

High hcg level in single and twin pregnancy
High hcg level in single and twin pregnancy

Pregnant women eagerly wait to know- how dark should a pregnancy test line be at 3 weeks? If you closely observe the pregnancy test lines, you’ll find darker lines than the previous week. But, it won’t be as dark as in the next few weeks. 

It could be astonishing that pregnancy test lines appear lighter. In general, test lines should get darker. You must know urine is used in the pregnancy test kit.

Urine could be diluted, you couldn’t have drunk sufficient water on the testing day.

As a result, hCG was hard to find in the kit, and the lines looked lighter.

Here are a few reasons behind getting pregnancy lines lighter at 3 weeks.  

  • Using a different brand’s testing kit could bring a big change in results. Their HCG detection capability might vary. That’s why using the same brand’s kit is the best choice for an unerring result.
  • A large number of people think the evaporation line and the pregnancy lines are the same. Evaporation lines are always faint, most often colorless. As it also appears in the result window, getting confused is natural. So, the pregnancy lines may be dark enough, but you’re wrong with your observation.
  • If you will observe the chemical pregnancy line progression, then pregnancy lines look lighter. This indicates a very early miscarriage that occurs during heavy implantation bleeding. The egg isn’t fully implanted into the uterus- that’s when this confusion arises. 

How dark should a pregnancy test line be at 4 weeks

The hCG level can rise to 426 mIU/ml at this stage. It’s possible to see faint lines even at this stage. The question is- how dark should a pregnancy test line be at 4 weeks? Well, the darkness should be improved, easily findable, and not as faint as the previous week. 

If you have a low HCG level, you may see faint lines. At this stage, your body forms the placenta and amniotic sac.

Despite having abdominal pressure and tender breasts, you can get sufficient darkness at 4 weeks. 

Interestingly, when you will be expecting twin babies then you will find the darkest spot. Here is why, the twins baby 4 to 5 weeks pregnancy test or progression is different.

How dark should a pregnancy test line be at 5 weeks?

5th-week pregnancy test lines are usually strongly dark. The pregnancy lines will be darker than any of the previous weeks. Your body will contain the hCG level of 18–7,340 mIU/ml. If you are suffering from pregnancy hormone deficiency, the range may vary. 

Should pregnancy test lines get darker at the 5th week?

Yes, the hormone level will be high enough at this stage. It’s much easier for the testing kit to detect hCG in the hormone. That’s why there is a high possibility of finding clear positive lines in the 5th week. 

How dark should a pregnancy test line be at 6 weeks?

When your pregnancy is in the 6th week, your hormone level will be extremely high. That means the hCG level is also extremely high. The range of hCG becomes around 1,080–56,500 mIU/ml at this stage.

So, how dark should a pregnancy test line be at 6 weeks?

The pregnancy lines appear with visible lines. Though slightly faint, any positive line assures you about your pregnancy. Also, this stage is most crucial for pregnant women in case they find faint lines. 

How dark should a pregnancy test line be at 7-8 weeks?

At 7–8 weeks, the pregnancy test lines are finally clear. Maximum women with proper body circulation must feel the presence of high hCG levels in their bodies. Generally, it ranges between 7,650–229,000 mIU/ml. The range is so high because of extreme hormonal responses. 

Are you eager to know how dark should a pregnancy test line be at 6 weeks?

Whatever your urine quality is, you’ll see dark line on pregnancy test. The lines will be significantly improved, dense and clear.

dark line on pregnancy test

Dark line on pregnancy test

With open eyes, you can easily distinguish between the lines of 6 and 8 weeks. 

Should pregnancy test lines get darker each day?

No, the hCG level increases exponentially in the early period of pregnancy. 

So, it’s not a rule of thumb that pregnancy lines should get darker each day. After every 2-3 days, hormone levels rise. And so, the line should be darker in a general sense. But, your biological factors may hinder your hormonal balance. As a result, you may not see darker lines every single day. 

Do pregnancy test lines get darker as hCG increases? 

Yes, there is a strong possibility of increasing the hCG level after a week.

ACOG Practice Bulletin 191 cited a multicenter retrospective study of 285 women that published revised and lower thresholds for the rate at which hCG increase could be considered consistent with possible viability

American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Gynecology. ACOG Practice Bulletin No. 193: Tubal Ectopic Pregnancy. Obstet Gynecol. 2018 Mar;131(3):e91-e103. doi: 10.1097/AOG.0000000000002560. Erratum in: Obstet Gynecol. 2019 May;133(5):1059. PMID: 29470343.

Another study has revealed that, hCG will increase up to 49% throughout the pregnancy life cycle.

Rauchfuss LK, Ainsworth AJ, Shenoy CC. Abnormal rate of human chorionic gonadotropin rise: a case series of patients with viable intrauterine pregnancies after embryo transfer. F S Rep. 2021 Feb 11;2(1):129-132. doi: 10.1016/j.xfre.2020.11.006. PMID: 34223284; PMCID: PMC8244357.

If you take proper rest and food and your body is running well, why not? But, you must remember that the lines won’t be extremely dark within the first 2-3 weeks. The more you wait, the darker the pregnancy lines you observe. 

Do pregnancy test lines get darker as it sits? 

When you test your pregnancy lines with urine, the results do not come on the screen rapidly. It takes time to collect information on hCG levels from your urine. So, if you observe the pregnancy lines after 10-15 minutes, the desired darkness will appear in front of you. However, this applies to any stage of your pregnancy. 

Pregnancy test lines getting darker day by day means your pregnancy period is running well. Sometimes, the hCG level may fall. As a result, the sequential dark appearance won’t be observed. An example of this problem is pregnancy test lines getting darker after miscarriage. 

Pregnancy test lines getting darker- is it a good sign? 

Yes, it’s a good sign because hormonal balance is still working nicely. Hormonal imbalance is a problem that may provide wrong information about your pregnancy.

There is one more problem- pregnancy test lines getting darker but bleeding. This bleeding is widely known as implantation bleeding. Bleeding occurs when a fertilized egg implants in the position of the uterus. This doesn’t last long and is not dangerous for pregnancy at all. 

Are pregnancy test lines fading?

Fading pregnancy test lines in the initial period isn’t anyone’s concern. But, the Pregnancy test line fading at 7 weeks could be a headache for many women. The fact is nothing but diluted urine is also responsible for this problem. Everything will be fine when you get the human Chorionic Gonadotropin hormone at the desired level. 

Pregnancy test lines also may not get expected darker every single week. A pregnancy test not getting darker at 5 weeks means your body isn’t receiving much water.

Urine is the key to changing this result. Therefore, focus on improving your urine quality, and bring it to normal condition.

Once you are done then run the urine test again.

Why is my pregnancy test getting lighter but no bleeding?

my pregnancy test getting lighter but no bleeding

The pregnancy test lines might also be lighter when there is no bleeding. Let’s check the possible reasons for getting pregnancy lines lighter even if there’s no bleeding.

Over Drinking water

Your body will get hydrated if you drink water before using the pregnancy kit. That means the percentage of water will increase in your body. The hormonal balance will be dismissed. It could be a possible reason for lighter pregnancy lines without bleeding.

Wrong observation

Evaporation lines may confuse your eyes. They’re always faint and colorless. If you continuously get lighter pregnancy lines without implantation bleeding, that could be your wrong observation.

Diluted urine

As mentioned earlier, drinking too much water may produce lighter pregnancy lines. Excessive water decreases the HCG level in urine. That means the pregnancy test lines will be darker.


Does a pregnancy test get lighter mean miscarriage?

Pregnancy tests getting lighter means getting faint positive lines. Yes, it’s a sign of very early miscarriage. This problem comes forward within the first 12 weeks of pregnancy. The test lines will be darker if you test again later. 

Does the darkness of a pregnancy test matter?

The darkness of a pregnancy test has no specific parameter to claim pregnancy. If you find positive lines, that means you’re possibly pregnant. The lines could be faint and hard to identify. But, if it’s not an evaporation line, then the darkness doesn’t matter to declare pregnancy. 


Reaching the endpoint, you have gained vast knowledge about pregnancy tests and how it becomes darker. Pregnancy test lines are good news for someone’s maternity. But, it’s natural to be worried to see zero improvements in test lines after weeks. 

Then the question arrives- should pregnancy test lines get darker? You already know that the natural rule is that the test lines become darker daily. Once it’s fully dark, there is no confusion about pregnancy. Even faint lines are acceptable except for evaporation lines.

But, some factors work behind to confuse your pregnancy condition. It could be hormonal imbalance, improper use of the testing kit, wrong reading, and so on. Now you know how to prevent pregnancy tests from getting lighter. Moving accordingly will bring you positive results with dark lines.

Sarah, a health writer and editor since 2014, is an adoring wife and dedicated mother to 2 daughters and 1 son. As the creator of Babies Plannet, she combines her extensive expertise with her maternal dedication to provide essential care and safety advice for infants, nurturing their well-being and happiness. Her writing explores topics like fitness, pregnancy, and women's healthy lifestyles.

0 0 votes
Article Rating
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments
Would love your thoughts, please comment.x