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C16 vs. C18 RAM: Does CAS Latency Really Matter?

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If you’re looking for a RAM upgrade that has an edge over its competitors, you’ll want to look at the key RAM specifications to see if they will deliver the performance and value for money you need. A key characteristic you may have come across if you are doing a PC build or gaming is a C16 or C18 RAM rating on the RAM module. 

Scratching your head? The “C” in C16 or C18 refers to Column Access Strobe (CAS) latency, which is known to affect memory access speed. And yes, it is another factor you may want to juggle when weighing up which RAM upgrade will give you the best performance and value for your money. 

For folks unfamiliar with memory timings and latency, this informative overview of C16 and C18 RAM will explain what these are and how they impact the performance of your computer.

C18 RAM (and C16 RAM) are types of synchronous dynamic random-access memory (SDRAM)

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What is C16 RAM?

C16 RAM is a type of synchronous DRAM that has a delay or latency of 16 clock cycles between the request for RAM data and the execution of the request. 

The “C” of C16 refers to CL or CAS, which is the Column Address Strobe latency of the module. CAS latency measures the delay between a read command and the availability of data. It’s easy to understand that this time interval should be kept as short as possible to provide better computer speed and performance. So, by comparing C16 and C18, you are comparing the difference in latency, measured in clock cycles. 

The memory timing of asynchronous RAM is measured in nanoseconds, but clock cycles for synchronous RAM have the operation of its external pin interface controlled by the CPU clock. This means that the clock frequency also contributes to just how fast a C16 RAM module is going to be. The same C16 RAM module can have vastly different overall speeds if placed in computers with different clock rates.  

C18 RAM is a Type of SDRAM

C18 RAM (and C16 RAM) are types of synchronous dynamic random-access memory (SDRAM). This modern RAM type was developed in the 1990s and is characterized by its use of synchronous interfaces, where input control signals are recognized after a rising edge of the clock input. 

The clock signal works by oscillating between high and low-frequency states to coordinate the various integrated circuits of the memory controller and memory. This metronome-like control coordinates the RAM’s processing of incoming commands. With each clock cycle, the RAM completes previously initiated operations and receives new commands.

SDRAM technology is standardized by JEDEC and is used widely because it achieves higher data transfer rates and can support multiple simultaneous computations on a synchronized basis. 

What is C18 RAM?

C18 RAM is synchronous DRAM that has a Column Address Strobe latency of 18 clock cycles. We can also express this as CAS18, CL18, or CAS 18 timings. This means that it takes 18 clock cycles between a memory request and the performance of the operation by the RAM. This latency is at least two clock cycles longer than C16 RAM, meaning it takes longer to execute the transfer of data from the RAM to the CPU following an instruction from the memory controller. 

C18 performs slower than C16 because of the increased number of clock cycles the RAM takes to perform a memory request. However, latency is not the only factor to consider when evaluating RAM performance. 

C16 RAM is Comprised of Multiple Memory Banks

This volatile memory of C16 SDRAM has a multi-memory bank architecture, each with rows and columns of storage units distributed across its chips. For most synchronous RAM, a single read/write operation accesses a single bank at a time. The memory controller and arrangement of the memory slots on the motherboard determine the format of the memory bank, with the size of the bank determined by the memory bus width.  

What’s the Difference Between C16 and C18 RAM?

The primary difference between C16 and C18 RAM is the two-clock cycle difference in the speed of execution of memory requests. This means that C16 RAM is faster and has lower latency than a C18 counterpart. 

The difference in latency is because of the properties and engineering of the integrated circuits that make up the memory chips in the module. As volatile microelectronic components, they require a certain amount of time to generate electrical signals, switch transitory, and charge their capacitors. These functions add latency to the RAM’s performance but are essential for the correct execution of commands and for preserving data integrity.

CAS Latency is Just One Aspect of the Memory Timing of C16 and C18 RAM

CAS latency is one of four parameters that specify the timing of SDRAM. The other parameters include: 

  • tRCD: row address to column delay
  • tRP: row pre-charge time
  • tRAS: row active time
  • Command rate 

The timings for each of these parameters, including CAS latency, are given in units of clock cycles. You’ll find the memory timings written as numbers on a RAM module in the format CAS-tRCD-tRP. The command rate may also be included.

Taken together, these parameters give an overview of the clock latency of the RAM. The lower the individual numbers, the better because it means that the RAM works faster. 

Your CAS latency affects your computer’s memory access speed, so figuring out whether you need C16 or C18 is crucial to your RAM upgrade.


The Memory Clock Frequency is Just as Important as CAS Latency

Though the CL rating gives you an idea of the latency of the RAM, absolute latency and the system performance you’ll experience are determined by the memory clock frequency as well as the memory timings.

The clock frequency is absolutely essential if you want to know if a C16 RAM module is really going to be faster than a C18 RAM module. The clock frequency determines the rate of the system clock and the actual length of the clock cycles. For double data rate SDRAM, the clock cycles are much faster than commonly quoted transfer rates.

C16 vs. C18 RAM: A Side-by-Side Comparison

What it is Memory module Memory module
Primary Use Storage of temporary system files Storage of temporary system files with an additional registry
Initial Release 1990s 1990s
Influential Developers Samsung, Hyundai, SK Hynix, Micron Technology, Nanya Technology Samsung, Hyundai, SK Hynix, Micron Technology, Nanya Technology
Technologies Influenced DDR SDRAM DDR SDRAM

Similarities and Differences


  • C16 and C18 RAM are types of volatile memory.
  • The CPU uses both types of RAM for the storage of temporary files and working data storage for operating system applications.
  • C16 and C18 RAM are types of SDRAM.
  • A memory controller controls both C16 and C18 buffered RAM.
  • The CPU uses both forms of RAM.


  • C16 RAM responds to data requests at a speed that is two clock cycles faster than C18 RAM.
  • These two RAM types may have latency differences because of their microcircuitry. 

What is C16 RAM Used for?

You can use C16 RAM for a variety of memory-hungry applications like:

  • Gaming
  • Video editing
  • Digital audio workstations
  • Virtualization

Compared to C18 RAM, C16 reads/writes with lower latency, providing a noticeable increase in speed and performance. However, C16 RAM is not the lowest latency RAM available; the lowest latency RAM available is the recently released 3200 MHz C14 RAM module by Taiwanese manufacturer G.Skill. 

Does C18 RAM Need to Be Upgraded?

Opinions vary on whether upgrading C18 RAM will make an appreciable difference to the performance of your computer. Upgrading RAM size, rank, and memory channels will have a bigger effect. For everyday computing, there are unlikely to be any gains from upgrading RAM because of latency or memory timings alone. 

RAM Frequency is Also a Consideration

RAM frequency is the actual speed at which your RAM operates. This is the number of cycles or mega transfers it can go through in one second. RAM frequency is measured in megahertz (MHz) and is usually quoted in the specification of the RAM (e.g. DDR4-3200).

The highest RAM frequencies that are widely available are in the 4266 MHz zone. This means that the RAM completes its cycles in less time and therefore can process more data.

An additional complication is that, at certain RAM speeds, the CPU becomes a rate-limiting factor and simply cannot process the data at the speed the RAM delivers. This means high-frequency RAM won’t benefit your system after a certain point.

C16 vs. C18 RAM: 6 Must-Know Facts

  • CAS latency measures the period between the supply of a column address and the receipt of the data. For DDR RAM, the CAS latency ranges between 10 and 15 nanoseconds.
  • C16 RAM has a delay or latency of 18 clock cycles between the request for RAM data and its execution. 
  • C18 RAM has a delay or latency of 16 clock cycles between the request for RAM data and its execution. 
  • C16 and C18 RAM are both types of SDRAM. 
  • CAS latency is only one of four factors, measured in clock cycles, that determine the absolute latency of RAM. 
  • The performance of a RAM module is equally dependent on RAM frequency and latency. 

Final Thoughts

CAS latency should certainly be considered when evaluating RAM modules for an upgrade, but this rating cannot be used in isolation. Alongside the CL, look at the RAM frequency and the clock frequency of your system. Other factors like RAM size and the number of channels available can deliver a significant uplift in system speed and performance. 


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C16 vs. C18 RAM: Does CAS Latency Really Matter? FAQs (Frequently Asked Questions) 

What is clock frequency?

Clock frequency, clock speed, and clock rate refer to the frequency of the pulses generated by a clock generator of a processor (CPU). These pulses are used to synchronize the operation of processor components and the function of SDRAM. Clock frequency is measured in clock cycles per second (Hertz).

What is CAS latency?

Column Address Strobe (CAS) is latency that is created by a delay (measured in clock cycles) between a read command and the presentation of the requested data.

What is tWR?

tWR is Write Recovery time. This latency parameter measures the clock cycles between writing data and a pre-charge command. This is necessary to ensure that all buffered data is written to the memory core.

What is tRAS?

tRAS stands for Row Active time, which measures the clock cycles between a bank active command and the pre-charge command.

What is tRCD?

tRCD is another latency parameter called the Row Address to Column Address Delay. It measures the clock cycles between an active command and the read/write command.

What is tWTR?

Internal Write to Read Command Delay, or tWTR, is a delay between ending the last data from a write operation to the memory and the issue of a read command. 

CL16 vs CL18 RAM: Which Is Better? What Should I Choose?

CL stands for “CAS (Column Access Strobe)  Latency” and is one factor that differs between different RAM sticks.

In short, CAS Latency determines how quickly your RAM can process and prepare data when ordered by the CPU. Let’s take an in-depth look at CAS Latency and how it affects your computing experience.

CAS Latency: An In-Depth Explanation

CAS Latency is measured in clock cycles.

When using Asynchronous DRAM, the delay is measured in nanoseconds. Synchronous DRAM typically uses clock cycles to measure the delay. A clock cycle is the measure of time used to track the delay between an order from the CPU to retrieve information from the memory column.

Typically CAS Latency will be denoted on the memory somewhere with a measure of CAS (number) or CL (number). Still, the timing doesn’t have a fully standardized measurement label.

So, ensure the RAM you’re buying has the CAS Latency you’re looking for. With CAS Latency, you’re typically looking for a lower number—thus a lower latency—rather than a high number. So CL 16 RAM will be a faster unit than CL 18 RAM.

Simply put, the CAS Latency is how long it takes for the RAM unit to access its memory column and make that information available to the RAM output and, thus, the computer controller or CPU.

CL 16 vs CL 18: What’s the Difference?

As we’ve mentioned, CL 16 RAM has a lower latency than CL 18 RAM.

However, that is the only notable difference on this axis. RAM sticks are measured on multiple axes that, together, provide a comprehensive view of what to expect from an individual RAM stick.

Many people confuse CAS Latency with Data Transfer Speed regarding RAM. However, these metrics are mainly independent, even if they work together in the overall RAM ecosystem. Therefore, to get a full view of what to expect from your RAM sticks, you’ll need to look at all the metrics and see how they interact.

CL 16 vs CL 18: How Do They Affect RAM Speed?

When looking at metrics regarding RAM speed, the two factors you want to look at most closely are the clock speed and the CAS Latency. Together, these two factors determine how quickly your RAM can read and write data.

If two RAM kits have the same clock speed, you’ll want to choose the kit with a lower CAS Latency. A faster CAS Latency will give you more speed in a set of kits with the same clock speed.

However, it’s not quite as simple if you’re looking at RAM kits with different clock speeds. Additionally, some units use a Latency Range. This feature allows the RAM sticks to adjust their latency speed based on the task they’re performing.

A CAS Latency Range of 14–16 is typical for RAM running at a clock speed of 3200 MHz. On the other hand, RAM with a clock speed of 3600 MHz typically features a CAS Latency Range of 15–19.

However, due to the functional speed boost achieved with a lower CAS Latency Range, the 3200 MHz/CL 14–16 RAM will outperform the 3600 MHz/CL 15–19 RAM.

Essentially, even though the 3600 MHz RAM transfers more data per clock cycle since the CL 14–16 RAM can retrieve data in upwards of three fewer clock cycles, it outperforms the CL 15–19 RAM in practice.

However, if both RAM kits have the same clock speed, CL 16 RAM will always surpass CL 18 RAM, even if only marginally.

CL 16 vs CL 18: RAM Latency

RAM latency is the overall speed at which your RAM can read and write, the speed it takes to complete one clock cycle.

While it may sound like it’s the same as your RAM speed, RAM latency has more factors than the raw speed of the RAM. For example, CAS Latency does affect overall RAM latency. So, you can’t forego this factor if you’re looking for the smoothest performance.

RAM Latency is typically measured in sequential numbers such as 6-8-8-22, which tell you how quickly your RAM can perform specific tasks. Unfortunately, the exact metrics and how they come to those conclusions are rather intricate and require much intimate knowledge of computer hardware. So, we won’t go too in-depth on how it works.

Instead, it would be best to look for a combination of high data transfer rates and low CAS latency to give your computer the best overall performance.

CL 16 vs CL 18: CPU Interfacing

Finally, you’ll want to check what kind of CPU you’re using to ensure perfect integration of your RAM into your computer ecosystem. The two major CPU manufacturers, AMD and Intel, interface with your RAM uniquely.

This uniqueness means that you’ll want to choose your RAM and CPU with the intention of them working together as a unified ecosystem rather than two separate components.

AMD Interfacing

Ryzen CPUs tend to be slightly nicer to your RAM than Intel CPUs. This differential is because Ryzen CPUs generally have faster memory speeds than their Intel counterparts.

This slight difference means that Ryzen CPUs can better use RAM sticks with a lower CAS Latency.

Ryzen CPUs are also unique in that they have unique clock time characteristics for the CPU cores and Ryzen CPU chips. The whole system ecosystem has a unique clock time as well.

These clock speeds are generally limited to around 1800 MHz–2000 MHz. The system functions most optimally when its RAM clock rate is around 2× the rate of the system clock rate.

Focusing on your RAM’s clock speed is unnecessary when you have a Ryzen CPU.

Instead, it would be most helpful if you ideally concentrate on getting the lowest possible CL RAM within your price range. Getting low-latency RAM will make the best use of the Ryzen chipset’s tight clock cycles.

Intel Interfacing

Intel CPUs are the polar opposite of AMD CPUs regarding RAM interfacing.

Unlike AMD, Intel CPUs don’t run at a tight clock speed. So, the data transfer rate is king with Intel CPUs. On the other hand, low-latency RAM typically comes at a lower data transfer rate.

So, if you’re looking to get the most out of your build—really milk every component for what it’s worth—you’ll want to buy 3600 MHz/CL 18 RAM and modify the RAM to run at a rate of CL 16.

With an Intel CPU, you’ll lose a lot of power and speed by “upgrading” to 3200 MHz/CL 16. To get the best of both worlds, you need to get under the hood and overclock your RAM to match the system build of your CPU.

If modifying your RAM is out of the question (a valid choice!), 3600 MHz/CL 18 RAM is more appropriate for an Intel build.

Will I Notice a Difference Between CL 16 and CL 18 RAM?

The truth is that unless you’re doing very intensive tasks like gaming, video editing, graphic design, or programming, you probably won’t see much difference between CL 16 and CL 18 RAM.

On average, CL 16 RAM is only about 1% faster than CL 18 RAM when used in ideal conditions.

So, suppose you’re looking at a hefty price tag. In that case, you might consider downgrading your RAM to CL 18 to offset some of the other more expensive components.

Final Thoughts

Understanding the inner workings of your computer is the first step to getting the most out of it.

RAM is just one component, but understanding the CAS Latency and how that affects your overall computing experience will help you get the most out of your computer and utilize your resources most effectively.

Delayed menstruation: signs, symptoms, what to do?



Yakha Akhmedovna

Experience 46 years

Obstetrician-gynecologist of the highest category, Ph.D.
Delayed menstruation is a failure of the menstrual cycle, which can be noticed by the absence of critical days in a period of 35 days or more. The symptom can occur at any age, as many reasons can lead to it.

If the discharge does not appear within 5-7 days, after which they make themselves felt, this is not a pathology. In the event that the failure lasts longer or occurs more than once, you should make an appointment with a gynecologist.


There is only one sign of a delay in menstruation — their absence. However, you should carefully consider your condition and observe how you feel. Additional symptoms may point to the cause of the failure. These include headaches, sudden weight gain or loss, nausea, increased sensitivity in the chest, general physical weakness, and others.

Main causes


There can be many reasons for delayed periods, but most often the delay occurs during pregnancy. So, if critical days do not occur, you should first take a pregnancy test (sold at any pharmacy). For the most accurate result, it is recommended to purchase 2-3 tests from different companies at once.

During pregnancy, a woman may experience mild nausea, sudden changes in mood, pain in the chest and swelling. The absence of additional symptoms does not exclude pregnancy.

In addition to the test, you can take an analysis for the content of chorionic gonadotropic hormone (hCG) in the body, which will give a more accurate answer.

If both examinations show the absence of pregnancy, and menstruation does not occur, it is necessary to contact a gynecologist as soon as possible to identify the exact cause.

Gynecological diseases

Ectopic pregnancy, polycystic ovaries, tumor formations in the female genital area, inflammation in the pelvic area — all this can lead to a failure of the menstrual cycle.

Most of these diseases need emergency diagnosis and treatment, so do not hesitate to visit a gynecologist.

Strong stress

A symptom of a missed period can provoke serious emotional or physical stress, mental overload, lack of rest.

Often, it is the failure of the menstrual cycle that overvoltage manifests itself. Thus, the woman’s body screams for help, and if it is not heard, other ailments may be added to the delay.

Climate change

A flight from a hot country to a cold one and vice versa, accompanied by a sharp change in sleep and wakefulness, often also entails a failure of the menstrual cycle.

In most cases, the situation will normalize on its own over time.


The standard rate of a delay in menstruation of 5-7 days can also be a call from the body for help if the failure is caused by following a strict diet.

Many women who want to quickly lose extra pounds often forget about health in the pursuit of harmony. Any diet should be carried out under the supervision of a specialist. In addition, in no case should you enter the diet abruptly, as a rapid entry entails stress for the body.

Therefore, it is important to balance your diet, preferably with the help of a professional nutritionist.

Hormonal changes in the body

A common reason for a delayed menstrual cycle is a hormonal failure associated with the thyroid gland. This is especially true of puberty or the threshold of menopause.

The same applies to long-term use, and then a sharp cessation of hormonal drugs.

In this case, the gynecologist may recommend a consultation with an endocrinologist.

Postnatal period

During pregnancy and for some time after childbirth, women experience a lack of menstruation.

You should not forget about the need for contraception after childbirth, since the absence of critical days does not mean the exclusion of unwanted pregnancy. The first ovulatory cycle, as a rule, begins imperceptibly for a woman, and without proper protection, she has a high chance of becoming pregnant.


Having found a long delay in critical days, as well as brown discharge during a delay in menstruation, you need to seek help from a specialist.

The following methods are used in the diagnostic process:

  • routine gynecological examination;
  • blood donation for the level of hCG, as well as the study of pituitary and ovarian hormones;
  • Ultrasound of the pelvic organs;
  • MRI and CT of the brain (in rare cases, if necessary).

It is advisable to conduct the examination in the same clinic where the specialist receives. The fact is that the analyzes of each laboratory have their own reference values, and the equipment has indicators. So the doctor will know exactly what is happening with the patient’s body.

In the absence of problems from the point of view of gynecology, the doctor may refer you for a consultation with a nutritionist, endocrinologist or psychotherapist.

Answers to common questions

Delayed menstruation: what to do?

With a delay of more than 5-7 days, you should do a pregnancy test (if there was sexual intercourse) and make an appointment with a gynecologist.

Is it possible to induce menstruation at home?

Any independent action can seriously harm health and, in particular, the reproductive system. It is strictly forbidden to do anything without prior agreement with the doctor.

How many days can be delayed menstruation?

The normal period for a delay is 5-7 days once. When the situation repeats, it is better to consult a gynecologist.

Can menstruation be accelerated?

It is impossible to accelerate their appearance without harming your health. Any stimulation can be fraught with serious complications.

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Delayed periods. What is delayed menstruation?

The information in this section should not be used for self-diagnosis or self-treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.

Delayed menstruation is a violation of menstrual function, manifested by the absence of cyclic bleeding for more than 35 days. May be due to physiological causes (pregnancy, premenopause, etc.), as well as various organic or functional disorders. The delay in menstruation occurs at various periods of a woman’s life: during the formation of menstrual function, in the reproductive period and in premenopause. A delay in menstruation for more than five days is a reason to see a doctor. Diagnosis of delayed menstruation is aimed at finding the main cause of this symptom, on which further treatment tactics depend.

    • Characteristics of the menstrual cycle
    • Missed period and pregnancy
    • Other causes of missed periods
    • Examination for missed periods
    • Prices for treatment


    Delayed menstruation is considered a failure in the menstrual cycle, in which menstrual bleeding does not occur at the expected time. A delay in menstruation, not exceeding 5-7 days, is not regarded as a pathology. Options for delaying menstruation are such menstrual disorders as oligomenorrhea, opsomenorrhea and amenorrhea, which are manifested by a decrease in menstrual bleeding. A delay in menstruation can be observed in different age periods of a woman’s life: during puberty, in the reproductive phase, in premenopause and be caused by physiological or pathological causes.

    Natural, physiological reasons for the delay in menstruation are explained in the puberty during the formation of the menstrual cycle, when menstruation can be irregular for 1-1.5 years. In women of reproductive age, a delay in menstruation is natural during pregnancy and during lactation. In the premenopausal period, the menstrual function gradually fades away, changes in the rhythm, duration of menstruation occur, and delays in menstruation are replaced by their complete cessation.

    All other options for delaying menstruation, exceeding 5-7 days, are not explained by natural phenomena, in such cases an urgent consultation with a gynecologist is required. The menstrual cycle of a woman is a delicate mechanism that maintains the reproductive function and reflects any deviations in the state of general health. Therefore, for a better understanding of the causes and mechanisms of delayed menstruation, it is necessary to clearly understand what is the norm and deviation in the characteristics of the menstrual cycle.

    Delay of menstruation

    Characteristics of the menstrual cycle

    The functioning of the body of a woman of childbearing age has cyclic patterns. Menstrual bleeding is the final stage of the menstrual cycle. Menstrual flow indicates that the fertilization of the egg and the onset of pregnancy did not occur. In addition, the regularity of menstruation indicates that the woman’s body is functioning smoothly. The delay in menstruation, on the contrary, indicates some failures that have occurred.

    The onset of the first menstruation usually occurs between 11-15 years of age. At first, menstrual bleeding may come irregularly, a delay in menstruation during this period is normal, but after 12-18 months, the menstrual cycle should finally form. The onset of menstruation before the age of 11 and the absence after 17 years is a pathology. A delay in the onset of menstruation up to 18-20 years indicates obvious pathological processes: a general lag in physical development, impaired function of the pituitary gland, underdevelopment of the ovaries, uterine hypoplasia, etc.

    Normally, menstruation comes and goes at regular intervals. In 60% of women, the cycle duration is 28 days, that is, 4 weeks, which corresponds to the lunar month. Approximately 30% of women have a cycle of 21 days, and about 10% of women have a menstrual cycle of 30-35 days. On average, menstrual bleeding lasts 3-7 days, and the allowable blood loss per menstruation is 50-150 ml. The complete cessation of menstruation occurs after 45-50 years and marks the onset of menopause.

    Irregularity and fluctuations in the duration of the menstrual cycle, systematic delays in menstruation for more than 5-10 days, alternation of scanty and heavy menstrual bleeding, indicate serious deviations in a woman’s health. In order to control the onset or delay of menstruation, every woman should keep a menstrual calendar, marking the day the next menstruation begins. In this case, the delay in menstruation will be immediately visible.

    Missed period and pregnancy

    Pregnancy is the most common cause of missed periods in women of childbearing age. The probable onset of pregnancy, in addition to the delay in menstruation, is evidenced by changes in taste and smell sensations, appetite, nausea and vomiting in the morning, drowsiness, and pain in the mammary glands. It is impossible to reject the possibility of pregnancy even in cases where there was interrupted intercourse, sexual contact during menstruation, on “safe” days or using a condom, in the presence of an intrauterine device, taking oral contraceptives, etc. , since neither one method of contraception does not give a 100% contraceptive effect.

    If there was a delay in menstruation, and in the previous month a woman had sexual intercourse, then it is possible to determine pregnancy using special tests. The principle of operation of all pregnancy tests (test strips, tablet or inkjet) is the same: they determine the presence of chorionic gonadotropic hormone (hCG or hCG) in the urine, the production of which begins in the body 7 days after fertilization of the egg. The concentration of hCG in the urine rises gradually, and modern, even the most sensitive tests, are able to determine it only after a delay in menstruation and not earlier than 12-14 days after the conception has occurred. It is necessary to “read” the test result in the first 5-10 minutes. The appearance during this period of time even a barely noticeable second strip indicates a positive result and the presence of pregnancy. If the second strip appeared later, then this result is not reliable. In case of a delay in menstruation, it is recommended to repeat the pregnancy test twice with an interval of 2-3 days to obtain a reliable result.

    It should be remembered that while living a sexual life, a woman can always become pregnant, so you need to carefully monitor the menstrual cycle and pay attention to delays in menstruation. However, a delay in menstruation can be caused not only by pregnancy, but also by a number of very different, sometimes very serious and dangerous to health reasons.

    Other causes of missed periods

    All the reasons that cause a delay in menstruation, gynecology conditionally divides into two large groups: physiological and pathological causes of delayed menstruation. In some cases, the delay in menstruation is caused by special transitional, adaptive conditions for the body, and usually does not exceed 5-7 days. However, some of these conditions are borderline, and when they worsen, organic disorders may occur, leading to a delay in menstruation as a manifestation of a particular pathology. Due to physiological reasons can be considered:

    • delay in menstruation caused by strong emotional or physical stress: stress, increased sports, school or work loads;
    • delay in menstruation due to unusual changes in lifestyle: a change in the nature of work, a sharp change in climate;
    • delayed periods due to malnutrition and strict diets;
    • delayed menstruation during periods of hormonal changes: puberty or menopause;
    • delayed menstruation as a condition after the abolition of hormonal contraceptives, caused by temporary hyperinhibition of the ovaries after a long-term intake of hormones from the outside. If the delay in menstruation is observed for 2-3 cycles, it is necessary to visit a gynecologist.
    • delay in menstruation after the use of emergency contraceptives containing a high dose of hormones;
    • delay in menstruation in the postpartum period associated with the production of the pituitary hormone prolactin, which is responsible for the secretion of milk and suppresses the cyclic function of the ovaries. If a woman is not breastfeeding, then menstruation should be restored approximately 2 months after childbirth. When breastfeeding, menstruation is restored after weaning the baby from the breast. However, if the delay in menstruation is more than a year after childbirth, it is necessary to consult a gynecologist.
    • delay in menstruation caused by colds (ARVI, influenza), chronic diseases: gastritis, thyroid dysfunction, diabetes, kidney disease, and more. etc., as well as taking certain medications.

    In all cases (except for those when the delay in menstruation is caused by age-related hormonal changes or lactation), the delay should not exceed 5-7 days, otherwise it is necessary to visit a gynecologist to prevent the development of serious diseases.

    The pathological causes of delayed menstruation include, first of all, diseases of the genital area. This group of reasons includes:

    • delayed menstruation caused by inflammatory (adnexitis, oophoritis) and tumor (uterine fibroids) diseases of the genital organs. Inflammatory processes in the genital organs, in addition to delaying menstruation, can be manifested by pathological discharge and pain in the lower abdomen. These conditions require emergency treatment, as they can lead to serious complications and infertility;
    • delayed menstruation due to polycystic ovaries and related hormonal disorders. Also, with polycystic ovaries, in addition to delayed menstruation, there is an increase in body weight, the appearance of seborrhea and acne, excessive hair growth;
    • delay in menstruation caused by a cyst of the corpus luteum of the ovary, which is formed due to a hormonal disorder. To resolve the cyst of the corpus luteum and restore the normal monthly cycle, the doctor prescribes a course of hormonal therapy;
    • delayed menstruation after an abortion, which, although quite common, is not the norm. The reason for the delay in menstruation after an abortion can be not only a sharp change in the hormonal state, but mechanical injuries inflicted during curettage of the uterus;
    • delayed menstruation due to missed or ectopic pregnancy, early miscarriage requiring emergency medical intervention;
    • delayed periods due to critical health gain or loss of weight. For women suffering from anorexia, a delay in menstruation can result in their complete cessation.

    Thus, regardless of the reasons, the delay in menstruation is the basis for an urgent visit to the gynecologist.

    Examination for missed periods

    To establish the reasons for the delay in menstruation, examinations may be required to supplement the gynecological examination:

    • measurement and graphic display of changes in basal temperature, allowing you to verify the presence or absence of ovulation;
    • determination in the blood of the level of hCG, hormones of the ovaries, pituitary gland and other glands;
    • ultrasound diagnosis of the pelvic organs to determine pregnancy (uterine, ectopic), tumor lesions of the uterus, ovaries and other causes that caused a delay in menstruation;
    • CT and MRI of the brain to exclude pituitary and ovarian tumors.

    When diseases associated with a delay in menstruation are detected, consultations of other specialist doctors are prescribed: an endocrinologist, a nutritionist, a psychotherapist, etc.

    Summing up the above, it should be noted that the delay in menstruation, no matter what circumstances it was caused, should not be left without the attention of a woman. A delay in menstruation can be caused by a banal change in the weather, or the joyful expectation of motherhood, or serious illnesses. If there is a delay in menstruation, a timely consultation with a doctor will free you from unnecessary worries and worries that can significantly aggravate this condition. In families where girls grow up, it is necessary to conduct their competent sexual education, explaining, among other things, that the delay in menstruation is a problem that must be solved together with the mother and the doctor.


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    Information from this section cannot be used for self-diagnosis and self-treatment. For the correct prescription of treatment, please contact your doctor.