Intrauterine devices (IUDs) are small, T-shaped contraceptive devices inserted into the uterus. Attached to the base of the device are one or two thin threads, commonly called IUD strings, which extend through the cervix and rest in the upper part of the vagina. These strings are not part of the contraceptive mechanism but serve a practical purpose, allowing a healthcare provider to confirm the device’s placement and later remove it. A common concern after insertion is the initial stiffness of the strings, which can sometimes cause discomfort for the user or their sexual partner.
The Initial Softening Timeline
The term “softening” for IUD strings is slightly misleading, as the threads are made from a medical-grade monofilament material, similar to thin plastic or nylon, which does not chemically dissolve or change texture significantly over time. Instead, the threads become less noticeable through physical adaptation and moisture absorption. This process results in the strings feeling more flexible and less “pokey” than they did immediately after the procedure.
The most important factor in reducing string sensation is the strings conforming to the anatomy by curling around the cervix. Over the first few weeks, the strings absorb the natural moisture of the vaginal environment, which increases their flexibility and helps them coil. Most users report that the strings become less bothersome within the first one to three months following insertion, allowing them to settle into a position where they lie flat against the cervix.
Factors Influencing String Texture and Comfort
The immediate sensation of the strings is heavily influenced by how they were trimmed during the insertion procedure. If the threads are cut very short, they may not have enough length to curl naturally, causing the sharp-cut ends to project outward and feel like a stiff stub. Conversely, if the strings are left slightly longer, they have more surface area to absorb moisture and are more likely to coil completely behind the cervix, making them essentially undetectable to a partner.
The position of the cervix is another major factor that affects how the strings feel throughout the menstrual cycle. The cervix naturally descends and is lower in the vaginal canal during menstruation, which can make the strings seem longer and more prominent. During ovulation and sexual arousal, the cervix typically retracts higher and softens, pulling the strings further up and making them less noticeable. The inherent material properties of the monofilament thread mean that they retain a degree of stiffness that can be perceived differently by various partners.
Addressing Discomfort During Intercourse
Partner discomfort, often described as a “poking” or “pricking” sensation, typically occurs during deep penetration when contact is made with the cervix. A simple initial step is to experiment with different sexual positions that limit the depth of penetration. Positions like “spooning” or those where the user is on top offer more control over the depth and angle of thrusting, reducing contact with the cervix.
Ensuring adequate lubrication is also a practical solution, as it reduces friction and irritation caused by the string ends. The use of a water-based lubricant can make the threads glide more smoothly, minimizing the sensation of a sharp edge. Since the cervix softens and pulls back slightly during sexual arousal, engaging in extended foreplay can help the strings retract naturally before penetration begins.
If discomfort persists after the initial adjustment period, a healthcare provider can trim the strings slightly shorter to encourage them to tuck more firmly behind the cervix. However, if the strings were already cut very short, further trimming is not advisable as it can exacerbate the issue by creating an even stiffer, more pointed end. Open communication with a partner and exploring non-penetrative activities are constructive steps while waiting for the strings to fully conform.
When to Consult a Healthcare Provider
While minor string discomfort is common, certain changes in string sensation warrant immediate consultation with a healthcare provider. If the strings suddenly feel much longer or shorter than they did during previous self-checks, this may indicate that the IUD has shifted or is partially expelled. If you can no longer locate the strings, medical confirmation of the device’s placement is necessary to ensure continued contraceptive protection.
You should also seek medical attention if you can feel the hard plastic or copper part of the device protruding through the cervix, as this is a clear sign of partial expulsion. The presence of severe or persistent pelvic pain, fever, chills, or unusual vaginal discharge can signal a complication like infection or device migration. Until a healthcare provider confirms the IUD is correctly positioned, a backup method of birth control should be used.