Embryo Transfer Catheter Balloon Design for Uterine Retention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The current embryo transfer process in IVF procedures faces challenges such as difficult catheter passage through the cervix, uterine contractions, sub-clinical infections, and reduced implantation success due to endometrial conditions, leading to variable success rates and potential embryo expulsion.

Innovation Solution

An embryo transfer catheter with an inflatable balloon at its distal end, designed to conform to the uterine shape and remain in situ for extended periods, minimizing physical disturbance and preventing embryo expulsion, along with a locking mechanism and therapeutic substance delivery system to enhance implantation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the catheter is made stiff to enable forceful passage through the cervix, then the catheter can be inserted more easily, but it causes irregular uterine contractions that may lead to ectopic pregnancies or embryo expulsion

Engineering Contradiction:
Improvecatheter insertionVSAvoiduterine contractions
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The catheter is divided into multiple sections with different flexibility characteristics. The proximal portion is stiffer to facilitate cervix penetration, while the distal portion is softer to minimize uterine irritation and contractions. This segmentation allows each part to perform its specific function optimally without causing harmful effects.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different sections of the catheter have locally optimized properties: the proximal section has higher rigidity for mechanical strength during insertion, while the distal section has lower rigidity to conform to uterine anatomy and reduce contractions. This local quality differentiation resolves the contradiction between insertion ease and contraction prevention.

Inventive Principle:
Principle #3Local quality

2Object-affected harmful factors

If the catheter is made soft to allow atraumatic passage, then uterine contractions are minimized, but the catheter cannot penetrate the cervix effectively

Engineering Contradiction:
Improveuterine contractionsVSAvoidcatheter insertion
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The catheter structure is segmented into a stiff proximal portion for cervix penetration and a soft distal portion for atraumatic uterine passage. This segmentation enables both hard and soft characteristics to coexist in a single catheter, resolving the contradiction between penetration ability and trauma prevention.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The catheter exhibits dynamic flexibility characteristics that allow it to be relatively stiff during the insertion phase for cervix penetration, then become more compliant once in the uterus to minimize contractions. The flexibility profile adapts to the different operational phases.

Inventive Principle:
Principle #15Dynamics

3Reliability

If the catheter remains in situ for extended periods to minimize physical disturbance, then implantation success is improved, but the risk of infection increases

Engineering Contradiction:
Improveimplantation successVSAvoidinfection risk
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The catheter is inserted and positioned in advance before embryo transfer, allowing the uterus to adapt and settle into a relaxed state. This preliminary positioning minimizes subsequent physical disturbance during the critical implantation period while the catheter remains in place to provide continuous support and stability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The catheter is designed as a single-use disposable device that maintains a sterile barrier throughout its brief period in situ. The sterile coating or covering is removed only at the moment of embryo transfer, and the catheter is then discarded, eliminating infection risk from prolonged use while maintaining sterility during the critical period.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

4Reliability

If a balloon is inflated to conform to the uterine shape for retention, then embryo expulsion is prevented, but the balloon may cause additional uterine contractions

Engineering Contradiction:
Improveembryo retentionVSAvoiduterine contractions
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The balloon is designed with non-uniform inflation characteristics, with greater volume concentrated in the lower uterine segment where it provides effective retention without excessive pressure on the fundus. This local quality distribution allows retention function while minimizing contraction-inducing pressure on sensitive areas.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The balloon inflation pressure and volume are carefully controlled and adjusted to achieve retention without over-inflation. By optimizing the pressure parameter, the balloon provides sufficient retention force while staying below the threshold that triggers uterine contractions.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The catheter design improves embryo retention and implantation success by reducing uterine contractions, minimizing infection risk, and optimizing endometrial contact, while allowing controlled release of therapeutic agents to promote implantation and pregnancy.

Implementation Method 1

an inflatable balloon (20) provided at a distal end of the first lumen (14), characterised in that the inflatable balloon (20) comprises first and second arms (22), which in an inflated state are adapted to extend upwards transversely within the uterus (18) at an angle approximating the slope of the inner transverse walls of the flattened uterine cavity, the shape of the balloon (20) being adapted in its inflated state to conform to just the lowest part of the uterus (18)

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

each arm (22) is augmented by an inferior protuberance (24) that when inflated enhances the seal of the balloon (20) to the lowest part of the uterus (18)

Methodology Applied
Scientific EffectPressure: Pressure Increase

Data Source

PatentEP2953558B1Embryo transfer catheter
Publication Date: 2019.08.28 SILLENDER MARK
  • EP2953558B1 patent drawingFigure 1
  • EP2953558B1 patent drawingFigure 2
  • EP2953558B1 patent drawingFigure 3~4

AI summary

An embryo transfer catheter (10) is described comprising an outer catheter body (12) having first and second lumens (14, 16). The second lumen (16) is adapted to receive an internal catheter (not shown) with a single lumen which, in use, will allow passage of an embryo or embryo-containing cannula (not shown) into the uterus (18) of the recipient. An inflatable balloon (20) is provided at a distal end of the first lumen (14). The inflatable balloon (20) is designed to be as small as possible in its inflated condition whilst still being retained in the uterus (18). The shape of the balloon (20) is adapted in its inflated state to conform to just the lowest part of the uterus (18). The aim in designing the balloon (20) as small as possible is to leave as much endometrium accessible to the embryo for implantation as possible, and to occupy as little volume as possible within the uterine cavity and to exert as little pressure as possible to avoid causing contractions, whilst still being retained in the uterus (18).