Tubal sterilization, often referred to as “getting your tubes tied,” is a procedure designed to provide permanent contraception. This process works by intentionally blocking the fallopian tubes, which are the pathways for an egg to travel from the ovary to the uterus. One of the most common methods for achieving this permanent blockage is through the application of mechanical devices, specifically rings or small clamps. These devices are positioned onto the tubes during minimally invasive laparoscopic surgery to create a physical barrier.
Appearance of Specific Sterilization Devices
The devices used for mechanical tubal occlusion are small, reflecting the delicate nature of the fallopian tubes. One common type is the Filshie clip, which looks much like a miniature, hinged jaw or a clothespin. This clip is approximately 14 millimeters long, 4 millimeters wide, and 3.4 millimeters high when fully closed. It is silver-gray titanium, lined with a soft, white silicone rubber cushion.
The Hulka clip presents a distinct visual difference from the Filshie clip. It is a hinged pincer-like device, typically made of a Lexan plastic body with a gold-plated stainless steel spring mechanism. It measures about 26 millimeters in length but is very thin at only 2 millimeters. The defining feature is the spring, which maintains constant pressure on the tube once the clip is locked.
In contrast to the clips, the Falope ring (also known as the Yoon ring) is a small, elastic band rather than a clamp. This ring is made from silastic, a highly flexible, medical-grade silicone rubber. It is applied by pulling a small loop of the fallopian tube into an applicator, and the ring is slipped over the base of this loop. The ring forms a tight band around the drawn-up section of the tube, creating a constricted knuckle.
How the Clamps Block the Fallopian Tubes
These mechanical devices achieve permanent sterility by inducing a localized obstruction in the fallopian tube. The surgeon places the clip or ring across the mid-isthmic portion of the tube, which is its narrowest segment. Once positioned, the device is closed, exerting constant pressure on the section of tissue it encompasses.
The compression from the device cuts off the blood supply to the constricted segment of the fallopian tube. This deprivation leads to avascular necrosis, meaning the tissue within the clamp or ring begins to die. The body absorbs this dead tissue over time, causing the fallopian tube to separate into two distinct, sealed segments.
This process of tissue death and absorption causes scarring (fibrosis), which permanently separates the two ends of the tube. The resulting physical barrier prevents the egg from traveling down the tube to meet sperm, and prevents sperm from reaching the egg. The original clip or ring remains in place, holding the two separated, scarred ends of the tube in close proximity.
Materials and Permanence of the Devices
The materials for these tubal occlusion devices are chosen for high biocompatibility and long-term durability within the human body. The Filshie clip is constructed primarily of titanium, a metal valued for its strength and resistance to corrosion. The clip’s interior is lined with silicone rubber to provide cushioning and maintain pressure as the tubal tissue shrinks.
The Hulka clip utilizes Lexan plastic for its body structure and a gold-plated stainless steel spring to ensure the locking mechanism remains secure. The Falope ring is made entirely of silastic, a type of silicone rubber, which is non-reactive and flexible. These medical-grade polymers and metals are intended to be non-corrosive and provoke a minimal immune response.
Once placed, these devices are considered permanent fixtures and are designed to stay in the body indefinitely. They function as a lasting marker and a physical constraint that maintains the separation of the tubal segments. These clips or rings are not intended to be removed after the sterilization effect is achieved.