Sedation without general anesthesia
Local anesthetic infiltration and intravenous sedation under anesthesiologist monitoring, without intubation in our protocol.
Many women considering MIA Femtech® or Preservé™ have postponed breast augmentation because of concerns about anesthesia, pain or complications. These approaches aim to limit tissue disruption. Our initial 160-patient series has been encouraging, but it is early clinical experience—not proof of zero risk or established long-term superiority.
Are MIA Femtech and Preservé safe?
Both can be appropriate options for carefully selected patients. Our early results compare favorably with our historical experience of conventional augmentation, but the groups were not randomized and follow-up is too short to establish that either technique is safer across all outcomes. In the 160-patient series reported in our August 2026 Spanish guide, no infections, hematomas requiring treatment, seromas requiring drainage or surgery, Baker II–IV capsular contractures, or permanent nipple-sensation loss had been diagnosed. One patient (0.6%) required implant replacement for an early rupture detected by ultrasound and recovered well.
These are observed results in a specific series, not a prediction of your individual risk. A complication can be uncommon and still important. We explain both its possible consequences and the limits of the available evidence. A small series with short follow-up cannot reliably estimate rare or late complications; an event not yet observed may still occur.
Sedation without general anesthesia
Median return to office work: day 3
This is the median in our reported series, with an estimated reduction in pain-medication use compared with our historical submuscular experience—not a guaranteed recovery time.
No infections or treated hematomas observed
No seromas required treatment and no Baker II or higher contracture was observed during the reported follow-up. This does not mean zero future risk.
A common concern before surgery
Our MIA and Preservé protocol uses local anesthesia and sedation
We infiltrate approximately 200 cc of a solution containing local anesthetic—not 200 cc of the active anesthetic drug. This provides local pain relief during the first hours and can make early recovery more comfortable.
An anesthesiologist also administers and monitors intravenous sedation. In our protocol, the patient breathes independently without intubation. Sedation still carries risks and requires appropriate monitoring; the individual anesthesia plan is confirmed by the team.
For some patients, this approach addresses concerns about general anesthesia. Discharge is often possible after 2–3 hours if all clinical criteria are met. Day-case discharge does not mean that postoperative support or follow-up is unnecessary.
In this article
Why do patients have questions about MIA and Preservé?
Questions about anesthesia, recovery, scars and complications are reasonable. So are questions about how new a technique is, what might happen in ten years, and whether a short procedure can be safe.
Our aim is to explain what is new, what can be learned from previous implant experience and what we have actually observed in our own patients—without dismissing concerns or implying that reassuring early results remove uncertainty.
A new placement method does not remove established implant risks
The main innovation is how the pocket is created and the implant inserted. The patient still has a silicone implant above the muscle and needs ongoing monitoring. Previous experience with related implants provides useful context, but it does not replace long-term follow-up of the specific technique and device.
A shorter operation, local anesthesia with sedation and less tissue manipulation may make the experience more manageable. Safety still depends on patient selection, planning, anesthesia care and follow-up.
What is new, and what stays the same?
Access and pocket creation
MIA uses a small armpit incision; Preservé uses the inframammary fold. Both use dedicated instruments and controlled expansion to reduce dissection and avoid dividing the pectoral muscle.
Long-term implant follow-up
A silicone implant still requires ongoing checks. Many patients return to normal activities, but implants are not lifetime devices and future treatment may be needed.
In most procedures in our experience, tissue expansion creates the pocket without internal cutting or electrocautery. In fewer than 5% of cases, a vessel has required direct coagulation or a ligament has needed division to allow expansion. We have not observed a meaningful difference between MIA and Preservé in this respect.
Several factors may contribute to recovery: muscle preservation, controlled expansion, smaller incisions, moderate implant volumes and local pain relief. Patient selection and expectations also affect observed outcomes. These factors cannot be separated by our uncontrolled clinical series.
In our practice, both techniques use prepectoral or subglandular placement. We measure the pinch test in every quadrant. Less than 1 cm usually excludes these techniques; 1–2 cm requires individual assessment. Around 1.5 cm is our usual practical minimum and 2 cm generally provides better coverage. These are clinic-specific criteria, not universal safety thresholds or guarantees.
It is therefore inaccurate to describe this as simply the same operation in the long term. Final implant position may resemble conventional subglandular augmentation, but access, instruments, implant design, dissection and the evidence for each procedure differ.
For more on how implant position affects coverage, movement and rippling, see our guide to implants above or below the muscle (Spanish).
Does armpit access pass near important structures?
The MIA incision lies near the pectoral border and the tunnel is subcutaneous. It is not intended to involve deep axillary dissection or the main nerves and vessels. Correct technique reduces risk, but no surgical approach is free of possible tissue or nerve injury.
MIA and Preservé are not identical
| Feature | MIA Femtech | Preservé |
|---|---|---|
| Access | Armpit, with the scar away from the breast. | Inframammary fold, allowing direct access from beneath the breast. |
| Implant | Biconvex Diamond, designed for MIA. Front-to-back orientation does not change its shape. | Ergonomix2 implants with a SmoothSilk surface, which can potentially undergo flipping like other ergonomic implants. |
| Volume | 165–195 cc; median 190 cc and most commonly 195 cc in our reported series. | 200–320 cc in our reported series, most commonly 250–285 cc. |
| Additional correction | Less scope to change the fold or correct asymmetry. | Allows selected additional adjustments in mild cases. |
| Shared limitations | Requires adequate tissue coverage and expectations of a modest increase. | Does not replace a full breast lift or correct marked anatomical changes by itself. |
For a patient seeking less than 200 cc, both may sometimes be suitable. The biconvex Diamond design offers a specific shape-related advantage if front-to-back flippingoccurs: orientation does not change the implant’s shape. This does not establish lower overall complication risk. Preservé offers more scope to alter the inframammary fold when indicated.
Front-to-back flipping of an ergonomic implant can deform the breast. In our experience with conventional augmentation, manual repositioning has often been difficult and revision surgery may be needed. None was observed among the 109 Preservé patients in the reported series, but cases may emerge with longer follow-up. Manufacturer warranty terms are a separate issue from biological safety.
Suitability and the exact implant model must be confirmed at consultation. Read more about MIA Femtech and Preservé breast augmentation.
Risks: what they mean and what our series observed
All implant-based augmentation has potential complications. Both AEMPS and the FDA recommend discussing these risks. Our early clinical observations are encouraging, but observed frequencies in a small, selected group should not be treated as definitive complication rates or proof of superiority over conventional augmentation.
Hematoma, seroma and infection
A hematoma is a blood collection; a seroma is a fluid collection. Infection can cause pain, redness or fever. In the reported 160-patient series, no infections, postoperative hematomas needing treatment or seromas requiring drainage or surgery were diagnosed. Small fluid layers seen on ultrasound were common and usually resolved without intervention; new symptoms still require assessment.
Pain, swelling and scars
Swelling and discomfort can occur. Our team estimates about 50% less pain-medication use, over fewer days, than in its historical submuscular practice. This is an uncontrolled observation, not a guaranteed reduction for an individual patient. Four patients (2.5%) required one to three reinforcing stitches in clinic for a superficial wound opening. None had implant exposure, infection or a keloid scar in the reported follow-up.
Capsular contracture
The tissue capsule around an implant can tighten, making the breast firmer, changing its shape or causing pain. No Baker II, III or IV contracture was observed among the 160 patients during the reported follow-up. Short follow-up limits this finding. Contracture can occur later; zero observed cases does not mean zero risk.
Rippling, displacement or asymmetry
Implant rippling means folds or wrinkles that may become visible or palpable under thin tissue. Mild rippling was observed in 5 of 160 patients (3.1%): three only when bending forward and two slightly when standing. None requested correction. No displacement, bottoming out or flipping was observed in the reported series. These remain possible complications.
Rupture and further surgery
An implant can rupture without obvious symptoms. Ultrasound detected an early unilateral rupture in 1 of 160 patients (0.6%). It was confirmed on removal and replaced through the same armpit incision, with a good recovery. This was the only reoperation reported in the series at that point.
Changes in sensation
Up to approximately 30% reported mild temporary increased sensitivity, especially centrally and around the nipple–areola complex. In our experience, this generally settled over around six months. Reduced sensation was reported very rarely, and no permanent nipple numbness was observed in the 160-patient series. Permanent changes remain a possible implant-surgery risk.
What about BIA-ALCL and other uncommon risks?
Breast implant-associated anaplastic large cell lymphoma is rare and is reported more often with textured implants. A smooth surface does not remove the need to investigate symptoms. The 2026 AEMPS surveillance report describes 111 confirmed cases reported in Spain from 2012 through 2025 and a stronger association with textured implants. These national reports are not a risk estimate for MIA or Preservé.
New, persistent breast swelling months or years after surgery needs clinical assessment. Depending on findings, ultrasound and testing of fluid or tissue may be appropriate.
Some patients report systemic symptoms described as breast implant illness (BII). The FDA acknowledges these reports and continuing uncertainty about their causes. Symptoms should be taken seriously and assessed without assuming either that an implant must be responsible or that the symptoms are unimportant.
What evidence is available, and what remains uncertain?
It is important to distinguish evidence about breast implants generally, evidence about incision and implant position, and studies of the specific MIA system or implant family. These do not answer exactly the same questions.
Long experience, but risks accumulate over time
Previous experience informs discussion of contracture, rupture and further surgery. It does not establish that implants last forever or that a new technique has identical outcomes.
Evidence about the approach, not MIA alone
A meta-analysis of 22 studies involving 5,843 patients found no statistically significant differences from other incisions in contracture, reoperation or infection. The evidence was heterogeneous; it is not a direct trial of MIA against Preservé.
Technique-specific follow-up is growing
A prospective study of 100 patients with three-year resultsprovides relevant evidence for MIA. Its sample size and duration still limit conclusions about rare or late events and suitability across different anatomies.
Published follow-up for an implant family
The Motiva SmoothSilk implant literature includes published five-year clinical data. This device-family evidence is not a five-year study of the Preservé surgical protocol and does not establish its superiority. The exact implant model also matters.
Existing evidence can reduce some uncertainty while technique-specific follow-up develops. It cannot remove the need for longer studies: rare complications and late outcomes require larger samples and more time.
Preliminary internal data · August 2026 report
160
consecutive patients
0 %
Baker II, III or IV
8 months
mean follow-up
Day 3
median return to office work
Ultrasound detection
Protocol adjustment
Bleeding control
Wound healing
What our MIA and Preservé series observed
The report covers 160 consecutive patients operated on from October 2024: 51 MIA and 109 Preservé. All had a one-month ultrasound; some did not attend subsequent reviews because they felt well. These are practice-based observations, not a comparative trial, and later events may be underestimated.
consecutive patients
51 MIA and 109 Preservé.
Baker II, III or IV
No contracture of these grades observed during the reported follow-up.
mean follow-up
Maximum follow-up: 22 months for MIA and 18 for Preservé.
median return to office work
No clinically meaningful pain difference observed between MIA and Preservé. Not a fitness-to-fly timeline.
| Observed outcome | Reported series | Interpretation |
|---|---|---|
| Infection | 0/160 | None diagnosed during the reported follow-up. |
| Postoperative hematoma | 0/160 | None required evacuation, drainage or further surgery. |
| Seroma requiring treatment | 0/160 | No fluid collection required ultrasound-guided drainage or surgery. Small self-resolving fluid layers were common. |
| Drains | 0/160 | None placed during or after surgery in this series. |
| Implant replacement | 1/160 (0.6%) | One confirmed early unilateral rupture in a MIA patient. |
| Displacement or bottoming out | 0/160 | No flipping was detected in the 109 Preservé patients; cases may emerge with longer follow-up. |
| Rippling visible | 5/160 (3.1%) | All mild: three visible only when bending and two slightly when standing. None requested correction. |
| Permanent sensory deficit | 0/160 | Up to approximately 30% reported mild temporary increased sensitivity; reduced sensitivity was reported very rarely. |
| Minor wound separation | 4/160 (2.5%) | Superficial openings treated in clinic; none exposed the implant or became infected. |
Cases that informed our practice
An early rupture without symptoms
A routine one-month ultrasound suggested a unilateral rupture in an asymptomatic MIA patient. It was confirmed when the implant was removed and replaced through the same armpit incision, with a good recovery. The cause could not be established; possibilities considered included delivery-related damage or a pre-existing device defect.
Temporary radial nerve dysfunction
One MIA patient developed unilateral radial neurapraxia, thought to be related to excessive arm abduction and a history of similar position-related episodes. She recovered fully within one week with conservative care. We subsequently limited arm abduction during MIA to 30 degrees; no further cases were reported in the series.
Two intraoperative checks during Preservé
Moderate bleeding prompted direct inspection through the same inframammary incision in two procedures, without conversion to another approach. In one, the incision was extended by 5 mm. When indicated, the balloon can also be repositioned briefly to apply pressure for hemostasis.
Four minor wound reinforcements
Three MIA armpit incisions required one to three simple stitches. One superficial 0.5 cm opening at the side of a Preservé incision was reinforced with a stitch for cosmetic reasons. No keloid scars were reported. The source describes increased use of barbed sutures to help reduce extrusion or wound separation.
How to interpret these findings
- No observed Baker II–IV contracture does not mean no risk. Cases may emerge as the series grows and follow-up lengthens.
- Our estimate of approximately 50% less pain-medication use and fewer days of analgesia than conventional submuscular augmentation is observational. It cannot separate the effects of implant position, technique, volume, anesthesia, selection and expectations.
- Mild increased sensitivity, especially centrally and around the nipple–areola complex, was reported in up to approximately 30%, generally settling over about six months. No persistent nipple numbness was observed in this series; that does not rule out the possibility.
- The five patients with rippling had limited tissue coverage, and some lost weight afterward. Cases occurred with both techniques, suggesting a possible tissue-related pattern, but the numbers are too small to establish a cause.
- No patient in the reported series had told the team she regretted surgery. One would choose surgery again but would now add a small lift for pre-existing drooping. This informal observation is not a validated measure of satisfaction or a guarantee.
MIA and Preservé results: individual examples of proportionate changes
Safety includes selecting an implant volume that the tissues can cover and that fits the patient’s goals. These four existing cases illustrate outcomes within the usual ranges. Photographs are educational examples, not evidence that another patient will obtain the same result.
MIA Femtech
Two examples with 190 cc
Modest increases with low-profile Diamond implants.
Preservé
Two examples with 225 and 270 cc
Moderate increases with moderate-profile ergonomic implants.
Who may not be a suitable candidate?
A wish for a quick recovery does not establish suitability for a prepectoral implant or a limited-volume technique. Patient selection is central to safety.
Insufficient tissue coverage
A pinch test below 1 cm usually excludes these techniques in our practice. Between 1 and 2 cm is assessed individually, with around 1.5 cm our usual practical minimum. Muscle coverage or another approach may be more appropriate.
Significant drooping
An implant alone does not truly lift the nipple. A breast lift may be needed, although selected anatomies may suit Preservé mastopexy.
A large-volume goal
MIA is intended for modest increases and Preservé for moderate augmentation. Pushing volume beyond what the tissues can support may affect coverage, stability and appearance.
Marked asymmetry
Large differences in shape, volume, folds or nipple position often require an approach with greater corrective scope.
Previous breast surgery
This may be a relative, rather than absolute, contraindication. Selected patients may be suitable after assessment of the capsule, pocket, existing implant and tissue quality.
Previous breast radiotherapy
We do not offer these techniques for an irradiated breast after cancer treatment. Radiation-related tissue changes require a different, individualized reconstructive plan.
Surgery may also be unsuitable or need postponement because of infection, an unresolved breast finding, uncontrolled anesthesia or healing risks, or incompatible expectations. No technique guarantees perfect symmetry, an exact cup size or freedom from future surgery.
Mild changes do not always exclude these options
Selected mild drooping or tuberous anatomy may allow additional correction, particularly with Preservé. Where a lift is required, trying to avoid it may leave drooping or lead to further surgery.
The source also describes an assessment of a patient operated on elsewhere with high-positioned MIA implants and a volume she considered excessive. Proposed correction had not been performed. This external case is not part of the clinic’s complication rates and cannot establish that the technique itself caused the outcome.
Follow-up and warning signs
Early discharge does not mean no follow-up. Our clinic’s minimum protocol includes checks at one week, one month, three months and one year, with ultrasound at each visit, followed by annual ultrasound even without symptoms. This is the clinic’s protocol, not a universal schedule. International patients must agree how these reviews will be completed after returning home.
The chest band is part of our protocol
Our MIA and Preservé patients use a chest band for the first two weeks. Implants may initially sit higher and gradually settle toward the preserved natural fold. Persistent position concerns need assessment. In uncomplicated cases with no improvement by three months, our source describes observation until around six months before considering revision; warning symptoms should never be left waiting on that timeline.
Contact the team promptly
- Sudden one-sided pain.
- Increasing asymmetry or breast swelling.
- Redness, warmth, discharge or fever.
- A sudden change in breast shape or implant position.
For one-sided pain or increasing asymmetry, our team usually arranges ultrasound. An obvious urgent complication may require treatment without delaying it for imaging. Seek urgent local medical care if symptoms are severe or you cannot reach the surgical team.
Small localized fluid layers can occur during recovery, but a tense collection, clear clinical asymmetry or infection signs require assessment. Patients should not try to decide at home whether a collection is harmless.
Do not ignore a later change
- New swelling months or years after surgery.
- Progressive hardening.
- A lump, fluid collection or enlarged lymph node.
- New pain or a change in shape.
A late seroma needs specific investigation. Our protocol may include ultrasound, guided fluid sampling, cytology and immunohistochemistry when indicated.
Routine one-month ultrasound detected the only early rupture reported in our series before symptoms developed. Imaging should be individualized to the implant, elapsed time, symptoms and applicable regulator/manufacturer recommendations. A normal examination does not make future monitoring unnecessary.
Frequently asked questions
Do MIA and Preservé require general anesthesia?
Our protocol uses infiltrated local anesthesia and intravenous sedation under an anesthesiologist’s care, without intubation. The patient breathes independently. Sedation still requires monitoring and has risks. Discharge is often possible after 2–3 hours if clinical criteria are met; the individual plan is confirmed before surgery.
Could a problem emerge later that is not yet known?
Yes. New information can emerge with longer follow-up. Previous experience with silicone implants provides context, but does not eliminate uncertainty about a specific device or placement method. Regular monitoring remains important as technique-specific evidence develops.
Can armpit access injure important nerves or blood vessels?
MIA uses a subcutaneous tunnel rather than deep axillary dissection, but surgical injury remains possible. Our series included one temporary radial neurapraxia thought to be related to arm position rather than the tunnel. It resolved in one week and led us to limit abduction to 30 degrees.
Do negative MIA reviews mean it is dangerous?
Not necessarily. Reviews may raise legitimate questions about novelty, limited implant volume, price, expectations or long-term evidence. These concerns should be assessed on their merits, neither treated automatically as proof of danger nor dismissed as misinformation.
Are MIA or Preservé lower-risk than conventional augmentation?
Our early experience suggests less tissue disruption, lower pain-medication use and favorable early outcomes in selected patients compared with our historical practice. This is not a randomized comparison, and follow-up is insufficient to establish superiority for all risks or time periods.
Do breast implants last a lifetime?
Implants should not be considered lifetime devices. An intact implant in an asymptomatic patient does not automatically require replacement at ten years, but rupture and further-surgery risk increase over time. Follow-up and individual assessment are necessary.
Can capsular contracture occur?
Yes. No Baker II–IV contracture was observed among our 160 reported patients, but mean follow-up was only about eight months. Cases may occur as follow-up lengthens. Zero observed cases is not a definitive long-term rate.
Can rippling occur with an implant above the muscle?
Yes, particularly with limited coverage or later weight loss. Our series reported mild rippling in 5 of 160 patients: three only when bending and two slightly when standing. None requested correction. We assess tissue coverage in every quadrant and individualize volume.
Does a quick recovery mean no pain medication?
No. Our protocol recommends pain relief for at least the first three days, tailored to the patient. Use was lower than in our historical submuscular experience, but we do not promise no pain or no medication.
Can I still have mammograms and ultrasound scans?
Yes. Tell the imaging center that you have breast implants so the examination can be adapted. Ultrasound and, when indicated, MRI can also assess implant integrity. Continue breast screening as advised for your age, history and country of residence.
What if I want the implants removed in the future?
Removal or replacement is possible but requires another operation. The result depends on time, implant volume, skin elasticity, capsule and natural breast changes. Some patients may also need a breast lift.
Safety depends on appropriate selection and ongoing follow-up
MIA and Preservé offer tissue-preserving options for selected patients. Our early series is encouraging, but reassurance should come from clear information, appropriate surgical planning, anesthesia care and follow-up—not a promise of zero risk. If you travel to Madrid, agree your stay, postoperative support, review schedule and fitness to fly before booking your return journey.
Discuss your individual risks with Dr. Aso
This guide is an English adaptation of Dr. Aso’s Spanish article. The internal clinical figures refer to its August 2026 report and are not a new audit or a substitute for an individual medical assessment. Dr. Aso speaks native-level English and has trained in the United States.
Initial consultations are 100 EUR. A video consultation can help start the discussion before traveling, but an in-person examination is needed to confirm surgical suitability.
Medical transparency
Medical authorship
Jorge Aso, MD, PhD
Specialist in Plastic, Aesthetic and Reconstructive Surgery (Spanish MIR training)
Medical registration no. 2828/61062 · Madrid
Original Spanish article updated
About MIA Femtech and Preservé: Safety, Risks and Suitability: clinical information, safety and expectations. Based on the original Spanish content.
Translation does not constitute a new medical review. This information does not replace an individual medical assessment.
View profile, training and credentialsMedical sources and editorial standards Selected references for this article 7 references
References support the general medical information. Suitability, alternatives, and risks are discussed individually during consultation.
- Patient information on breast implants Spanish Agency of Medicines and Medical Devices (AEMPS)
- Information on monitoring the protocol for detecting breast implant-associated ALCL Spanish Agency of Medicines and Medical Devices (AEMPS)
- Risks and Complications of Breast Implants U.S. Food and Drug Administration (FDA)
- 3-Year Results of a 100-Patient Prospective Study of the Safety and Effectiveness of Mia Femtech Aesthetic Surgery Journal / PubMed
- The Study of the Safety and Effectiveness of Motiva SmoothSilk Silicone Gel-filled Breast Implants: 5-Year Clinical Data Aesthetic Surgery Journal / PubMed
- A Systematic Review and Meta-Analysis of 11,686 Breasts Undergoing Transaxillary Augmentation Plastic and Reconstructive Surgery / PubMed
- Comparison of POLYTECH MESMO and Motiva Ergonomix Breast Implants With Focus on Displacement Issues Aesthetic Surgery Journal / PubMed
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