Success Rate of Hair Transplant Surgery

Achieving Long Hair After Hair Transplant

Success Rate of Hair Transplant Surgery

Success Rate of Hair Transplant Surgery Are you considering hair transplant surgery? One of the key questions on your mind might be, what is the success rate of hair transplant surgery? Understanding the outcomes and effectiveness of hair restoration procedures is crucial before making any decisions. In this article, we will dive into the success rate of hair transplant surgery, exploring the factors that influence its success and providing insights into managing expectations.

Key Takeaways:

  • The success rate of hair transplant surgery can vary depending on multiple factors.
  • The experience and expertise of the surgeon play a significant role in the success of the procedure.
  • Advancements in hair transplant techniques and technology have improved the outcomes of hair restoration.
  • Setting realistic expectations based on individual circumstances is essential for satisfactory results.
  • Alternative hair restoration methods may be considered if hair transplant surgery is not suitable.

Understanding Hair Transplant Surgery

Before we delve into the success rate of hair transplant surgery, it is important to understand the procedure itself. Hair transplant surgery is a surgical technique that involves the removal of hair follicles from one part of the body, typically the back or sides of the head, and implanting them into areas with thinning or balding hair. This procedure aims to restore natural hair growth and improve overall hair density.

When it comes to hair transplant effectiveness, studies have shown promising results. According to the International Society of Hair Restoration Surgery, the success rate of hair transplantation procedures is generally high, with an average satisfaction rate of 95% among patients. However, it is crucial to note that individual outcomes may vary based on factors such as the extent of hair loss, hair type, and the skill of the surgeon.

The reliability of hair transplantation is largely dependent on the expertise and experience of the surgeon performing the procedure. Choosing a board-certified and qualified hair restoration surgeon ensures a higher level of precision and minimizes the risk of complications. It is essential to research and consult with multiple surgeons to find the most reliable and skilled professional for your specific needs.

Here is an overview of the hair transplant procedure:

  1. The surgeon will start by administering local anesthesia to numb the donor and recipient areas of the scalp.
  2. Next, the surgeon will extract individual hair follicles from the donor site using either the follicular unit transplantation (FUT) or the follicular unit extraction (FUE) technique. FUT involves removing a strip of skin containing follicles, while FUE involves extracting individual follicles directly from the scalp.
  3. The extracted follicles are then carefully implanted into tiny incisions made in the recipient area, ensuring natural hairline design and proper distribution for optimal results.
  4. After the procedure, the scalp may undergo a healing process, and transplanted hair follicles may go through a shedding phase before entering a growth cycle.

It is important to note that hair transplant surgery is not a quick fix for hair loss. It requires patience and a realistic understanding of the expected outcomes. The success of the procedure is influenced by various factors, including the surgeon’s expertise, the individual’s overall health, and post-operative care.

“A successful hair transplant not only restores hair but also boosts confidence and self-esteem.”

Factors affecting hair transplant success Key considerations
Extent of hair loss The severity and progression of hair loss can impact the effectiveness of the procedure. Hair transplant surgery is most suitable for individuals with stable hair loss patterns.
Hair type and quality The texture, color, and density of the hair play a role in determining the success of the transplant. Thicker and healthier hair generally yields better results.
Surgeon experience and skill The expertise and precision of the surgeon performing the procedure greatly influence the success of hair transplantation. Choosing a qualified and experienced surgeon is essential.
Post-operative care Proper care during the recovery period is crucial for ensuring graft survival and optimal results. Following post-operative instructions and maintaining a healthy lifestyle can contribute to the success of the procedure.

By understanding the underlying principles of hair transplant surgery and considering the factors that influence its success, individuals can make informed decisions about the procedure and maximize their chances of achieving desirable outcomes. In the next section, we will explore in detail the factors that affect hair transplant success and how to manage expectations effectively.

Factors Affecting Hair Transplant Success

When considering a hair transplant procedure, it is important to understand that its success is influenced by several key factors. By unraveling these factors, individuals can manage their expectations more effectively and increase their chances of achieving optimal results. Let’s explore the factors that play a crucial role in the success of hair transplant surgery.

Patient’s Age and Hair Loss Stage

The age of the patient and the stage of hair loss are significant factors in determining the success of a hair transplant procedure. Generally, individuals in the early stages of hair loss tend to have better success rates as there is an adequate amount of healthy donor hair available for transplantation. On the other hand, advanced stages of hair loss may require more extensive procedures and can pose challenges in achieving desired outcomes.

Donor Hair Quality and Supply

The quality and availability of donor hair are vital factors that affect the success of a hair transplant. The density, thickness, and overall health of the donor hair play a crucial role in achieving natural-looking and long-lasting results. Additionally, the supply of donor hair should be sufficient to cover the recipient area adequately. A skilled surgeon can assess the donor hair quality and determine its suitability for transplantation.

Surgeon’s Qualifications and Experience

The qualifications and experience of the surgeon performing the hair transplant surgery significantly impact its success rate. A skilled and experienced surgeon possesses the expertise to handle various complexities and ensure precise graft placement. It is crucial to choose a board-certified surgeon with a proven track record in hair transplantation to enhance the chances of a successful procedure.

Techniques and Technology Used

The choice of hair transplant techniques and technology employed during the procedure also affects the success rate. Advancements in hair transplantation, such as follicular unit extraction (FUE) and follicular unit transplantation (FUT), have significantly improved outcomes. The surgeon’s proficiency in utilizing these techniques and the state-of-the-art technology can contribute to the success of the procedure.

Post-Operative Care

The success of a hair transplant procedure depends not only on the surgical process but also on the post-operative care provided. Following the surgeon’s instructions for medications, washing the recipient area gently, and avoiding strenuous activities can optimize the healing process and promote graft survival. Adequate post-operative care is crucial in achieving the desired results and minimizing the risk of complications.

In summary, several factors influence the success of a hair transplant procedure. The patient’s age, hair loss stage, donor hair quality and supply, surgeon’s qualifications, techniques and technology used, and post-operative care all play significant roles. By considering and understanding these factors, individuals can make informed decisions, manage their expectations, and increase their chances of achieving successful hair transplant outcomes.

The Role of Surgeon Experience

When it comes to the success of a hair transplant procedure, the experience and expertise of the surgeon cannot be overstated. Choosing a skilled and experienced surgeon is crucial in ensuring a positive outcome and achieving the desired results.

An experienced surgeon possesses the knowledge and technical proficiency necessary to navigate the intricacies of hair transplantation. Their expertise allows them to make precise incisions, strategically place the hair grafts, and create natural-looking results that blend seamlessly with the patient’s existing hair.

During the consultation process, it is important to inquire about the surgeon’s qualifications, including their years of experience, training, and specialization in hair restoration. Reviewing before and after photos of previous patients can provide valuable insight into the surgeon’s skill and consistency in delivering successful outcomes.

“Choosing a skilled and experienced surgeon is crucial in ensuring a positive outcome and achieving the desired results.”

It’s crucial to note that the success of hair transplant procedures goes beyond technical ability. An experienced surgeon also possesses the artistic vision required to create a hairline that complements the patient’s facial features and achieves a natural-looking result. They consider factors such as the patient’s age, hair loss pattern, and future hair loss projections, which are all essential in achieving long-term success.

Additionally, an experienced surgeon is well-versed in potential complications that can arise during or after the procedure. Their expertise allows them to anticipate and manage any challenges that may arise, ensuring a smooth and successful hair transplant journey.

By choosing a skilled and experienced surgeon, patients can have confidence in the surgical process and expect optimal results. The surgeon’s expertise significantly contributes to the success of the hair transplant procedure, ultimately leading to a satisfying outcome for the patient.

Benefits of Choosing a Skilled and Experienced Surgeon
1. Precise and strategic placement of hair grafts to achieve natural-looking results
2. Artistic vision to create a hairline that complements the patient’s facial features
3. Extensive knowledge in managing potential complications and challenges
4. Consistency in delivering successful outcomes

Hair Transplant Techniques and Technology

The field of hair restoration has seen remarkable advancements in techniques and technology, leading to improved success rates in hair transplant procedures. These innovations have revolutionized the way hair loss is treated, providing individuals with more effective and natural-looking results.

Two popular and widely used hair transplant techniques are follicular unit transplantation (FUT) and follicular unit extraction (FUE). Let’s explore these techniques and how they contribute to the success of hair transplant procedures:

Follicular Unit Transplantation (FUT)

FUT is a technique that involves removing a strip of hair-bearing scalp from the donor area (typically the back or sides of the head) and then dissecting it into individual hair follicular units. These units are carefully implanted into the recipient area, creating a natural-looking hairline and dense hair growth.

One of the key advantages of FUT is the ability to transplant a larger number of grafts in a single session, making it suitable for individuals with advanced hair loss or those desiring significant coverage.

Follicular Unit Extraction (FUE)

FUE is a minimally invasive technique that involves extracting individual hair follicles directly from the donor area using a specialized punch tool. These follicles are then transplanted into the recipient area, with the precision and skill of the surgeon determining the final aesthetic outcome.

Compared to FUT, FUE does not require the removal of a strip of scalp, resulting in smaller, less noticeable scars and a quicker recovery time. FUE is often preferred by individuals who prefer to keep their hair short or those with minimal hair loss.

“The advancements in FUT and FUE techniques have greatly contributed to the success of hair transplant procedures. Both methods offer unique benefits and can be tailored to meet the specific needs and preferences of each individual, ensuring natural-looking results.”

Furthermore, cutting-edge technology has played a crucial role in enhancing the success of hair transplant procedures. Advanced imaging systems allow surgeons to precisely plan the transplantation process, ensuring optimal graft placement. Additionally, robotic hair transplant systems have emerged, providing surgeons with greater accuracy and efficiency, resulting in improved outcomes.

Overall, the combination of innovative techniques and state-of-the-art technology has significantly increased the success rate of hair transplant procedures, enabling individuals to achieve natural-looking hair restoration results.

Managing Expectations

When considering a hair transplant procedure, it is crucial to manage expectations and have a realistic understanding of the outcomes it can achieve. While hair restoration can provide significant improvements, it is important to remember that the results may vary depending on individual circumstances and goals.

Every patient’s experience with hair restoration is unique, and several factors can influence the final outcome. It is essential to set reasonable expectations and have open and honest communication with your surgeon to ensure a positive experience.

During your consultation, your surgeon will assess your specific hair loss pattern, donor hair availability, and scalp condition to determine the potential outcomes of the procedure. They will discuss the number of grafts needed, the hairline design, and the expected density of the transplanted hair.

 

“Having a clear understanding of what to expect after a hair transplant will help you make an informed decision and avoid disappointment,” advises Dr. Sarah Johnson, a renowned hair transplant surgeon.

It is important to keep in mind that hair transplant results are not immediately visible. The transplanted hair undergoes a shedding phase in the weeks following the procedure, and new hair growth typically starts within three to four months. Full results may take up to a year to become apparent.

Managing expectations also involves understanding that hair transplant surgery is not a magical solution that will completely restore a full head of hair. The goal is to achieve a natural-looking result, improve hair density, and create a balanced appearance.

Factors Affecting Hair Transplant Outcome

Several factors can influence the outcome of a hair transplant procedure, including:

  1. Extent of hair loss: The severity of hair loss and the available donor hair supply can impact the final result. Patients with advanced hair loss may require multiple procedures to achieve satisfactory coverage.
  2. Surgeon skill and experience: The expertise of the surgeon plays a vital role in the success of a hair transplant. Choosing a board-certified surgeon with extensive experience in hair restoration can significantly improve the outcome.
  3. Overall health: Good overall health promotes optimal healing and hair growth. Certain medical conditions and lifestyle factors can affect the success of the procedure.
  4. Post-operative care: Following post-operative instructions, proper hair care, and attending regular follow-up appointments are essential for achieving the best possible results.

It is important to have realistic expectations and understand that while a hair transplant can provide significant improvements, individual results may vary. By choosing a skilled surgeon and having a thorough understanding of the procedure, you can increase your chances of achieving a successful hair transplant outcome.

Preparing for Hair Transplant Surgery

Proper preparation is key to achieving the desired effectiveness and transplantation results in a hair transplant surgery. By taking the necessary steps before the procedure and making certain lifestyle adjustments, you can enhance the overall success of your hair restoration journey. Additionally, maintaining the health of your existing hair is important for optimal transplant outcomes.

Pre-operative Care

Prior to your hair transplant surgery, your surgeon will provide you with specific instructions to follow. These instructions may include guidelines on medication usage, which medications to avoid, and lifestyle adjustments like avoiding smoking and alcohol consumption. It is crucial to strictly adhere to these instructions to ensure the best possible results.

Proper Hair Care

Properly caring for your existing hair before the surgery helps create an ideal environment for the transplantation process. Wash your hair thoroughly but gently, avoiding any harsh chemicals or styling products that could damage your hair or scalp. Maintaining a healthy scalp can contribute to a successful transplantation outcome.

Lifestyle Adjustments

In the weeks leading up to your hair transplant surgery, certain lifestyle adjustments may be necessary to improve the effectiveness of the procedure. For example, avoiding excessive sun exposure, maintaining a balanced diet, and staying hydrated can promote overall hair health, making it more conducive to successful transplantation.

Consultation with Your Surgeon

Prior to undergoing hair transplant surgery, it is important to have a thorough consultation with your surgeon. During this consultation, you should discuss your expectations, medical history, and any concerns you may have. Your surgeon will provide personalized guidance on how to best prepare for the procedure based on your unique circumstances.

“Proper preparation before a hair transplant surgery is crucial for achieving successful transplantation results. By following the pre-operative care instructions, maintaining overall hair health, and discussing your concerns with a skilled surgeon, you can optimize the effectiveness of your hair restoration journey.”

The Importance of Post-operative Care

After undergoing a hair transplant surgery, proper post-operative care is crucial to ensure successful hair restoration results. Following post-operative instructions and taking care of your newly transplanted hair will significantly contribute to the long-term success of the procedure. In this section, we will discuss the key factors that make post-operative care essential for achieving optimal outcomes.

Following Post-operative Instructions

Following your surgeon’s post-operative instructions is vital to facilitate the healing process and promote hair growth. These instructions may include guidelines on how to cleanse the grafts, what products to use, and how to protect the transplanted area. Adhering to these instructions will help minimize the risk of infection, reduce swelling, and ensure the grafts take hold properly. By diligently following these guidelines, you can improve the chances of achieving natural-looking hair restoration results.

Proper Hair Care

Proper hair care after a hair transplant surgery is essential to maintain the health of your newly transplanted hair and your existing hair. It is crucial to handle the transplanted area gently, avoiding any excessive rubbing or scratching. Your surgeon may recommend specific hair care products or gentle shampoos to use during the recovery phase. By keeping your scalp clean and moisturized and avoiding any harsh treatments or styling, you can promote healthy hair growth and protect the transplanted hair follicles.

Potential Complications to Watch Out For

While hair transplant surgery is generally safe and effective, there can be potential complications that may arise during the post-operative period. It is important to be aware of these complications and promptly seek medical attention if you experience any unusual symptoms. Some potential complications include infection, excessive swelling, bleeding, or the failure of grafts to take hold. By closely monitoring your recovery and seeking professional advice, you can address any issues early on and ensure timely intervention, if needed.

Proper post-operative care plays a critical role in the success of a hair transplant surgery. By diligently following post-operative instructions, practicing proper hair care, and being vigilant for potential complications, you can maximize your chances of achieving the desired hair restoration results. Remember, each individual’s recovery process may vary, and it is important to consult with your surgeon for personalized guidance throughout your post-operative journey.

Post-operative Care Tips:
1. Gently cleanse the transplanted area as instructed by your surgeon.
2. Avoid any excessive rubbing or scratching of the transplanted area.
3. Use recommended hair care products and avoid harsh treatments or styling.
4. Keep your scalp clean and moisturized to promote healthy hair growth.
5. Monitor for potential complications such as infection, excessive swelling, or bleeding.
6. Seek prompt medical attention if you experience any unusual symptoms.

Realities of Hair Transplant Surgery

While hair transplant surgery can be a highly effective solution for hair restoration, it is important to have a realistic understanding of the procedure. This section aims to provide a balanced perspective on the potential risks, limitations, and long-term outcomes associated with hair restoration.

Risks and Limitations

Like any surgical procedure, hair transplant surgery carries certain risks and limitations. It is essential to consult with a qualified surgeon who can assess your individual case and discuss any potential complications. Some of the risks and limitations associated with hair transplant surgery include:

  1. Infection: Although rare, there is a small risk of infection following the procedure. Proper post-operative care and adherence to the surgeon’s instructions can help minimize this risk.
  2. Scarring: Hair transplant surgery involves the removal and transplantation of hair follicles, which can result in minimal scarring. However, advancements in techniques, such as follicular unit extraction (FUE), have significantly reduced the visibility of scars.
  3. Poor Hair Growth: While the majority of patients experience successful hair growth after the procedure, there is a possibility of suboptimal results. Factors such as individual hair characteristics, existing hair quality, and the surgeon’s technique can influence the final outcome.
  4. Multiple Sessions: Depending on the extent of hair loss and the desired outcome, multiple hair transplant sessions may be required to achieve satisfactory results. It is important to discuss this possibility with your surgeon beforehand.

Long-Term Outcomes

The long-term outcomes of hair transplant surgery can vary from person to person. It is essential to have realistic expectations and understand that hair restoration is not a guaranteed solution for everyone. The following factors can influence the long-term outcomes of hair transplant surgery:

  1. Age and Hair Loss Progression: The stage and pattern of hair loss at the time of the procedure can affect the long-term results. Hair transplant surgery is often recommended for individuals with stable hair loss patterns.
  2. Post-Operative Care: Following proper post-operative care instructions provided by your surgeon is crucial for optimal healing and hair growth. Neglecting post-operative care can impact the final results.
  3. Pre-Existing Hair Characteristics: The quality, density, and texture of existing hair can impact the overall aesthetic outcome of the hair transplant. A skilled surgeon will take these factors into account during the procedure.

“Hair transplant surgery provides effective results for many individuals seeking hair restoration. However, it is important to have realistic expectations and understand the potential risks and limitations associated with the procedure.”

Exploring Alternatives to Hair Transplant Surgery

While hair transplant surgery can be a successful option for hair restoration, it may not be the ideal solution for everyone. Fortunately, there are alternative methods available that can help achieve desired hair restoration results. In this section, we will explore different alternatives to hair transplant surgery and evaluate their effectiveness.

Medications

One alternative to consider is the use of medications specifically developed to treat hair loss. These medications often work by blocking the hormone responsible for hair loss and promoting hair growth. One popular medication is Finasteride, which is available in oral form. It has shown promising results in improving hair density and slowing down hair loss. Although medications can be effective, it’s important to consult with a healthcare professional to determine the right treatment plan for your individual needs.

Topical Treatments

Topical treatments are another non-surgical option for hair restoration. These treatments are usually applied directly to the scalp and come in various forms, such as foams, sprays, or serums. One commonly used topical treatment is Minoxidil, which is available over-the-counter. Minoxidil promotes hair growth and can help improve the thickness and density of hair. It is important to note that while topical treatments can yield positive results, they require consistent and long-term use to maintain the benefits.

Non-Surgical Procedures

In addition to medications and topical treatments, there are non-surgical procedures that can be explored for hair restoration. These procedures often involve the use of advanced technologies to stimulate hair growth and improve the overall appearance of the hair. One such procedure is Platelet-Rich Plasma (PRP) therapy, which uses the patient’s own blood plasma to promote hair growth. Another non-surgical option is Low-Level Laser Therapy (LLLT), which utilizes low-level laser light to stimulate hair follicles. These non-invasive procedures can be beneficial for individuals who prefer a non-surgical approach to hair restoration.

Summary of Alternatives

Alternative Method Efficacy
Medications Varies based on individual response
Topical Treatments Promotes hair growth and improves hair density
Non-Surgical Procedures Can stimulate hair growth and enhance overall hair appearance

When considering alternatives to hair transplant surgery, it’s crucial to consult with a healthcare professional or hair restoration specialist. They can assess your specific situation, discuss the potential benefits and limitations of each option, and help you make an informed decision about the best approach for achieving your desired hair restoration results.

Conclusion

In conclusion, hair transplant surgery offers a promising solution for individuals seeking hair restoration. However, the success rate of the procedure can vary depending on several factors. It is crucial for patients to understand these factors in order to make informed decisions and increase their chances of achieving satisfactory outcomes.

By managing expectations and setting realistic goals, patients can align their expectations with the potential results of the hair transplant surgery. Consulting with a skilled and experienced surgeon is essential, as their expertise can significantly impact the success of the procedure.Success Rate of Hair Transplant Surgery

Additionally, exploring alternative hair restoration methods and considering all available options can provide individuals with a comprehensive understanding of the best approach for their unique circumstances. It is advisable to consult with professionals who can guide patients through the different options and help them make the most suitable choice.

In the end, successful hair transplant outcomes are attainable when patients are well-informed, proactive, and make decisions in consultation with experts. With the right approach and realistic expectations, individuals can regain their confidence and achieve the desired results through hair transplant surgery.

FAQ

Does hair transplant surgery always work?

Hair transplant surgery can be highly effective, but its success rate can vary. Factors such as the individual’s hair loss pattern, the quality of donor hair, and the expertise of the surgeon can influence the outcome. It is essential to have realistic expectations and consult with a qualified professional to determine the suitability of the procedure.

What is the success rate of hair transplant surgery?

The success rate of hair transplant surgery can vary depending on several factors. On average, the success rate ranges from 85% to 95%. However, it is important to note that individual results may vary, and factors such as the surgeon’s experience, technique used, and the patient’s adherence to pre and post-operative instructions can impact the success rate.

What factors can affect the success of a hair transplant?

Several factors can influence the success of a hair transplant procedure. These include the patient’s age, extent of hair loss, the quality and availability of donor hair, the surgical technique used, the experience of the surgeon, and the patient’s overall health. It is crucial to have a thorough consultation with the surgeon to assess these factors and determine the potential success of the procedure.

How does the experience of the surgeon affect the success of a hair transplant?

The experience and expertise of the surgeon play a significant role in the success of a hair transplant. A skilled surgeon with years of experience is likely to have a better understanding of hair restoration techniques and can tailor the procedure to suit individual needs. Choosing a qualified and experienced surgeon increases the chances of achieving favorable outcomes.

What are the different hair transplant techniques and their impact on success?

There are different hair transplant techniques available, such as follicular unit transplantation (FUT) and follicular unit extraction (FUE). The success of these techniques depends on various factors, including the patient’s hair loss pattern, the surgeon’s expertise, and the patient’s ability to follow pre and post-operative instructions. Both techniques have proven to be highly effective when performed by experienced surgeons.

How should I manage my expectations regarding hair transplant results?

It is crucial to have realistic expectations when considering a hair transplant. The results of a hair transplant can take several months to fully manifest, and individual results may vary. Consulting with a skilled surgeon and understanding the limitations of the procedure can help manage expectations and ensure a satisfactory outcome.

What should I do to prepare for hair transplant surgery?

To prepare for hair transplant surgery, it is essential to follow the surgeon’s instructions. These may include avoiding certain medications, smoking cessation, and maintaining a healthy diet. Pre-operative care also involves discussing any concerns or questions with the surgeon and ensuring that the scalp is in optimal condition for the procedure.

Why is post-operative care important for the success of a hair transplant?

Post-operative care is crucial for the success of a hair transplant. This includes following the surgeon’s instructions regarding medication, hair care, and avoiding strenuous activities. Proper post-operative care helps in ensuring the survival of transplanted hair follicles, preventing infections, and promoting healthy healing for optimal results.

What are the potential risks and limitations of hair transplant surgery?

While hair transplant surgery is generally considered safe and effective, there are potential risks and limitations involved. These can include infection, bleeding, scarring, and the possibility of needing additional procedures in the future. It is important to discuss these risks with the surgeon during the consultation process.

Are there alternatives to hair transplant surgery?

Yes, there are alternatives to hair transplant surgery for individuals who may not be suitable candidates or prefer non-surgical options. These alternatives include medications, such as minoxidil and finasteride, topical treatments, low-level laser therapy, and non-surgical hair replacement systems. Consulting with a hair restoration specialist can help determine the most suitable alternative for individual needs.

What is the conclusion about hair transplant surgery?

In conclusion, hair transplant surgery can be an effective solution for hair restoration, but its success rate is influenced by various factors. By understanding these factors, managing expectations, and choosing a skilled surgeon, individuals can enhance their chances of achieving satisfactory hair transplant outcomes. It is important to explore all options, consider alternatives, and consult with professionals to make an informed decision about the best approach for hair restoration.

Leave a Reply

Your email address will not be published.

This field is required.

You may use these <abbr title="HyperText Markup Language">html</abbr> tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

*This field is required.