Understanding the Hormonal Coil (IUS): Your Guide to Contraception

BlogContraceptive Coils

Written by

Catherine Smith

Published on

November 5, 2024
Young woman smiling at the camera while holding an IUD in her hand

Did you know that fewer than 1 in 100 women using a hormonal coil become pregnant within the first year? This statistic highlights the remarkable effectiveness of the intrauterine system (IUS), a leading form of long-acting reversible contraception. If you’re considering your contraceptive options, the hormonal coil could be the ideal choice for you.

The IUS, a small T-shaped plastic device, is inserted into the uterus and can provide reliable contraception for up to 8 years. It functions by releasing a progestogen hormone, which thickens cervical mucus and thins the uterine lining. This creates an inhospitable environment for sperm. In some instances, it may even halt ovulation altogether.

Unlike its copper counterpart, which can last up to 10 years without hormones, the hormonal coil offers additional benefits beyond contraception. It is suitable for most women, including those who’ve never been pregnant, and can be used while breastfeeding. With its long-lasting protection and minimal maintenance, the IUS has become a preferred choice for many seeking hassle-free contraception.

Key Takeaways

  • The hormonal coil (IUS) is over 99% effective at preventing pregnancy
  • It can provide contraception for up to 8 years, depending on the type
  • The IUS releases progestogen hormone to prevent pregnancy
  • It’s suitable for most women, including those who’ve never been pregnant
  • The hormonal coil can be used while breastfeeding
  • It offers additional benefits beyond contraception

What is a Hormonal Coil (IUS)?

A hormonal coil, commonly referred to as an intrauterine system (IUS), is a T-shaped device inserted into the womb for contraceptive purposes. The prevalent models include Mirena and Jaydess. These devices release progestogen, a hormone that effectively prevents pregnancy.

Mirena, being larger, is designed to last up to eight years, boasting an efficacy rate of over 99%. For women aged 45 or older, it can remain in place until menopause. In contrast, Jaydess, with its smaller size and lower progestogen dosage, is effective for up to three years.

The IUS features two thin threads that extend through the cervix into the vagina. These threads are palpable, allowing users to verify the device’s correct positioning. A healthcare professional can remove the IUS by gently pulling on these threads.

Unlike certain contraceptives, the hormonal coil begins its contraceptive function immediately upon insertion, provided it is done within a week of the menstrual cycle’s onset. Its benefits extend beyond contraception; it can also alleviate heavy menstrual periods. In fact, Mirena has proven to be effective in preventing surgical interventions for such conditions in 2 out of 3 women.

How Hormone-Based Coils Work

The hormone-based coil, or IUS, releases progestogen into your uterus. This device functions in several ways to prevent pregnancy. It thickens cervical mucus, creating a barrier that sperm find difficult to traverse. The progestogen also thins the uterine lining, making it less conducive for a fertilised egg to implant.

In some instances, the IUS may halt ovulation. The IUS begins to work immediately if inserted within the first week of your menstrual cycle.

The efficacy of hormone-based coils is noteworthy. They boast over 99% effectiveness in preventing pregnancy, with fewer than 1 in 100 users experiencing pregnancy over 3 to 8 years of use. If inserted during the first five days of your period, you are immediately protected against pregnancy.

Beyond contraception, hormone-based coils offer additional health benefits. They can lower your risk of ovarian cancer, endometrial cancer, and pelvic inflammatory disease. You can retain a hormone-based coil for up to 10 years depending on the type and age of insertion making it a convenient long-term option.

Benefits of Using an IUS

The intrauterine system (IUS) presents numerous advantages for women in search of effective contraception. It stands out for its long-lasting protection, spanning 3 to 8 years, contingent on the model. Its high efficacy, surpassing 99%, underscores its reliability in preventing pregnancy.

One of its most significant benefits is the potential for lighter menstrual periods. Many women report a decrease in menstrual flow and alleviated cramps post-insertion. This feature is invaluable for those burdened by heavy bleeding or menstrual pain.

The IUS’s reversibility is another notable aspect, allowing for quick fertility restoration upon removal. It is also compatible with breastfeeding, making it an ideal choice for new mothers. Unlike some contraceptives, it does not hinder sexual intercourse, promoting convenience and spontaneity.

For women nearing menopause, the IUS can be integrated into hormone replacement therapy (HRT). It delivers localised hormones, aiding in the management of menopausal symptoms while serving as a contraceptive. Its safety for those unable to use estrogen-based contraceptives broadens the range of options available to women.

The IUS Insertion Process

The procedure for fitting an IUS occurs in a clinic or GP surgery. A trained professional, either a doctor or nurse, administers the fitting, which generally takes 10-15 minutes. You might experience some discomfort, but a local anaesthetic can alleviate this. The healthcare provider will first examine your uterus and cervix before proceeding.

The timing for IUS insertion is flexible. It can be done at any point in your menstrual cycle, excluding pregnancy. Post-pregnancy insertion is also viable, with some women choosing to have it fitted immediately after childbirth or following a miscarriage.

During the fitting, the IUS is inserted through your cervix into your uterus with precision. Post-insertion, a follow-up appointment is necessary within 3-6 weeks to confirm everything is functioning correctly. It’s noteworthy that less than 1% of users become pregnant within a year, highlighting its effectiveness as a contraceptive method.

Though rare, there’s a small risk of the IUS perforating the uterus during insertion. This risk is slightly elevated immediately post-childbirth. Despite this, the IUS remains a preferred choice, with certain types effective for up to eight years.

Potential Side Effects and Risks

The hormonal coil boasts an efficacy rate of over 99%. Yet, it’s crucial to acknowledge potential side effects. Irregular bleeding or spotting may occur in the initial six months post-insertion. Some individuals might experience headaches, acne, or breast tenderness. These symptoms typically diminish as the body adapts to the device.

There are, albeit rare, risks to consider. Pelvic infection poses a risk, predominantly within the first 20 days following insertion. The possibility of IUS expulsion or displacement exists, albeit infrequently. During the fitting procedure, a small risk of uterine perforation is present, though this is extremely rare when conducted by a skilled professional.

It’s important to note that while the risk of ectopic pregnancy is lower with an IUS compared to no contraception, it remains a concern if pregnancy occurs. If pregnancy is suspected while using an IUS, immediate medical consultation is advised.

Despite these potential complications, millions have utilised hormonal IUDs safely for decades. The benefits often surpass the risks for many. If concerns regarding side effects or risks arise, it is imperative to engage in dialogue with your healthcare provider.

Conclusion

The hormonal coil (IUS) emerges as a premier choice for long-acting reversible contraception. It transcends mere pregnancy prevention, offering significant benefits for sexual health and family planning. With a failure rate under 1%, it ranks among the most dependable contraceptive methods.

Studies affirm the IUS, notably Mirena®, surpasses oral contraceptives in managing heavy menstrual flow. It can reduce blood loss by an additional 67ml compared to pills. Its long-term adherence is higher, and its effects on fertility are rapidly reversible, making it perfect for those planning a family.

Despite its numerous advantages, it’s vital to acknowledge potential side effects. Users may encounter initial cramping, light spotting, or mood swings. It’s important to note that the IUS does not protect against sexually transmitted infections (STIs), necessitating the use of condoms. Regular consultations with healthcare professionals are imperative to monitor its efficacy and safety.

The selection of contraception is an intensely personal decision. The hormonal coil might be the ideal choice for you, but it’s essential to discuss all options with a healthcare provider. They will guide you in selecting the most suitable method for your lifestyle and health requirements.

FAQ

What is a hormonal IUD and how does it differ from a copper coil?

A hormonal IUD, also known as an intrauterine system (IUS), is a type of contraceptive device that releases the hormone levonorgestrel. Unlike the copper coil, which is hormone-free, the hormonal IUD works by thickening cervical mucus and thinning the lining of the uterus. This method of contraception is highly effective and can last for several years.

How effective is the Mirena coil as a contraceptive method?

The Mirena coil, a popular type of hormonal IUD, is extremely effective as a method of contraception. It’s over 99% effective at preventing pregnancy, making it one of the most reliable forms of birth control available. Once fitted, it can provide contraception for up to 8 years, although it can be removed earlier if desired.

What are the common side effects of using a hormonal IUD?

Common side effects of using a hormonal IUD may include irregular bleeding or spotting, especially in the first 3-6 months after insertion. Some women may experience hormonal side effects such as headaches, acne, or mood changes. However, many women experience lighter and less painful periods over time. There’s a very small risk of the device moving out of place or perforating the uterus during insertion.

Can a hormonal IUD help with heavy menstrual bleeding?

Yes, a hormonal IUD like the Mirena coil can significantly reduce heavy menstrual bleeding. The levonorgestrel released by the device thins the lining of the uterus, which often results in lighter and shorter periods. For this reason, hormonal IUDs are sometimes prescribed as a treatment for heavy periods, even for women who don’t need contraception.

How is a contraceptive coil fitted, and is the procedure painful?

A contraceptive coil is fitted by a trained healthcare professional in a clinic or doctor’s office. The procedure involves inserting the small, T-shaped device through the cervix and into the uterus. While some women may experience discomfort or cramping during insertion, the procedure is usually quick and can be done with local anesthesia if needed. Many women find that the insertion is less painful than they expected.

Can a hormonal IUD be used as part of hormone replacement therapy during menopause?

Yes, certain types of hormonal IUDs, such as the Mirena coil, can be used as part of hormone replacement therapy (HRT) during menopause. The levonorgestrel released by the IUD can help protect the lining of the uterus when used in combination with estrogen therapy. This approach can be particularly beneficial for women who experience heavy bleeding during perimenopause.

How soon after having a hormonal IUD fitted can I rely on it for contraception?

The timing of contraceptive effectiveness depends on when in your menstrual cycle the hormonal IUD is inserted. If it’s fitted within the first 7 days of your menstrual cycle, it’s effective immediately. If it’s inserted at any other time, you should use additional contraception for 7 days after insertion to ensure you’re protected against pregnancy.

Can I still get pregnant after removing my hormonal IUD?

Yes, fertility typically returns quickly after removing a hormonal IUD. The contraceptive effects of the device wear off as soon as it’s removed, and most women return to their normal fertility within a few months. If you don’t want to get pregnant after removal, it’s important to start using another form of contraception immediately.

Dr Catherine Smith

Dr Catherine Smith is the founder of The Coil Clinic. A GP and Women's Health Expert with nearly 20 years of experience. She is a BMS Certified Menopause Specialist