The recent incorporation of Implanon into the Unified Health System (SUS) represents an important advancement in access to long-acting contraceptive methods in Brazil. The implant, which can cost thousands of reais in private clinics, is now being made available for free, with plans for large-scale distribution over the coming years.

However, despite expanded access, the decision to use Implanon should be conscious and individualized. Below, you will find a complete guide, based on scientific evidence, explained in a clear manner.

What is Implanon and how does it work

Implanon is a small flexible rod placed under the skin of the arm that continuously releases a hormone called etonogestrel for up to 3 years.

It prevents pregnancy in two main ways:

  • Prevents ovulation

  • Makes cervical mucus thicker, making it difficult for sperm to enter

It is considered one of the most effective contraceptive methods available, with an extremely low failure rate.

Who can have it placed through SUS

Access through SUS is being expanded progressively. Initially, some groups had priority (such as women in specific health or vulnerability situations), but the current proposal is to expand access to women of reproductive age.

In practice, the criteria may vary depending on the local organization of the health service, including:

  • Prior medical evaluation

  • Absence of contraindications

  • Availability of the method in the network

In other words: it is not just about "wanting to have it placed" there is a care flow that needs to be followed.

Who can use it (and who should not)

Can use:

  • Women who want a long-acting method

  • Those who have difficulty remembering daily contraceptive use

  • Those who cannot use estrogen (e.g., certain clinical conditions)

Should not use:

  • Pregnancy or suspected pregnancy

  • History of active thrombosis

  • Severe liver disease

  • Hormone-sensitive cancer

  • Uterine bleeding without a definite diagnosis

Additionally, some medications may interfere with effectiveness, which requires individual evaluation.

Do you need to have tests done beforehand?

Not always.

In most cases, clinical diagnosis and medical evaluation are sufficient. The main thing is to rule out pregnancy and identify contraindications.

Tests may be requested if there are specific concerns, such as:

  • Significant menstrual irregularity

  • Liver disease

  • Associated clinical situations

What to know before having it placed

Here is a critical point many patients have Implanon placed without fully understanding the impact on their body.

You mainly need to know about the bleeding pattern.

Bleeding: the most common effect (and most underestimated)

Implanon does not maintain a predictable menstrual cycle.

What can happen:

  • Irregular bleeding

  • Frequent light spotting

  • Complete absence of menstruation

  • Or, in some cases, prolonged bleeding

Important:
This does NOT mean that the method is not working.

But:
If the bleeding is heavy or persistent, medical evaluation is necessary.

Acne, skin, and weight: what to expect in practice

Acne

It can happen it is a relatively common effect.

  • Some women experience worsening

  • Others show no change

It is not possible to predict with precision before use.

Weight

Weight gain is not the rule, but it can occur in some users.
Often it is related to increased appetite, and not directly to the hormone.

Other possible effects

  • Headache

  • Mood changes

  • Breast tenderness

  • Decreased libido

  • Pain at the implant site

How to prepare for side effects

Here comes an important strategic guidance:

The greatest factor for success with Implanon is not the method itself it is having the correct expectation.

Before having it placed, you need to know:

  • Bleeding can change completely

  • Your body needs time to adapt (especially in the first few months)

  • Not every adverse effect requires immediate removal

Practical strategies:

  • Follow-up in the first few months

  • Re-evaluation if symptoms persist

  • Individualized adjustments, when necessary

Is it worth it?

From a medical standpoint, Implanon is:
✔ Highly effective
✔ Safe for most women
✔ Convenient (does not depend on daily use)

But:
It is not the best method for everyone

The main factor of dissatisfaction is not method failure it is intolerance to the bleeding pattern.

Implanon represents an important advancement in public health by expanding access to a modern and effective contraceptive method.

However, the choice should be individualized, based on medical evaluation and, most importantly, on clear information about benefits and possible effects.

This content is informative in nature and does not replace a medical consultation. In case of doubt or for personalized evaluation, consult a health professional.

Dr. Rebeca Soares Andrade CRM-GO 39335