Dozens of common gynecologic and obstetric procedures require passing an instrument, device, or catheter through the cervix and into the uterus. The cervix is densely innervated and often tightly closed, which is why these procedures can range from mildly uncomfortable to genuinely painful depending on the person, the technique, and whether any pain management is used. Despite how routine these insertions are, clinical guidelines on pain control during them have been slow to develop, and many patients still undergo them with little or no anesthesia.
What Happens During Cervical Insertion
The cervix sits at the lower end of the uterus and connects it to the vaginal canal through a narrow passage called the cervical canal. Any procedure that needs access to the uterine cavity has to navigate this canal. The most common reason people encounter the term is IUD placement, but the same basic process applies to embryo transfers during fertility treatment, Foley catheter insertion for labor induction, endometrial biopsies, hysteroscopies, and several other office procedures.
A typical IUD insertion, for example, involves three steps that each produce their own sensation. First, the provider stabilizes the cervix, usually by grasping it with a tenaculum (a clamp-like instrument with small teeth). Then a thin rod called a sound is passed through the cervical canal to measure the depth of the uterus. Finally, the IUD itself is loaded into a narrow inserter tube and guided through the canal into position. Each of those steps can trigger cramping, sharp pain, or pressure, and the intensity varies enormously from person to person.
Why It Hurts and How Much
The cervix and surrounding pelvic organs have a complex web of sensory nerves, which makes pinpointing and blocking pain difficult. Researchers have identified a number of potential targets on the sensory neurons that supply the reproductive tract, but basic knowledge of how those neurons behave remains limited compared to other internal organs.1Europe PMC / Frontiers in Pharmacology. Female reproductive tract pain: targets, challenges, and outcomes That gap in understanding partly explains why pain management for cervical procedures has lagged behind other areas of medicine.
Pain scores during IUD insertion, measured on a standard visual scale, land all over the map. In randomized trials, control-group averages for the insertion step alone have ranged from around 30 to above 50 on a 100-point scale, depending on the study population.2PubMed Central. Paracervical Block for Intrauterine Device Placement Among Nulliparous Women: A Randomized Controlled Trial People who have never given birth vaginally tend to report higher scores, because their cervical canal has never been stretched by labor. But anatomy is only part of the picture.
Pre-procedure anxiety and negative expectations turn out to be powerful amplifiers. One study found that while a history of cesarean delivery and pre-procedure anxiety were both linked to higher pain, the single strongest predictor was holding negative perceptions about IUDs before the procedure even started.3PubMed. The relationship between pain at IUD insertion and negative perceptions, anxiety and previous mode of delivery Separately, a randomized trial of music during IUD insertion confirmed a strong positive correlation between post-procedure anxiety and pain intensity, and a negative correlation between anxiety and procedural satisfaction.4PubMed Central. Effect of Music on Pain, Anxiety, and Satisfaction During Intrauterine Device Application: A Randomized Clinical Trial In plain terms, the more worried you are going in, the more it tends to hurt and the less satisfied you are afterward.
Pain Management That Works and What Doesn’t
For years, many providers offered ibuprofen before insertion and little else. That is starting to change, but the landscape of options is still surprisingly muddled. A 2025 consensus from the American College of Obstetricians and Gynecologists acknowledged that common in-office procedures like IUD insertion are routinely performed with no or inadequate pain management, and that what patients receive often depends more on the provider’s preferences and institutional policies than on evidence.5Obstetrics & Gynecology. Pain Management for In-Office Uterine and Cervical Procedures
Paracervical Block
The strongest evidence supports a local anesthetic injection called a paracervical block. This involves injecting lidocaine into the tissue around the cervix before the procedure begins. In a randomized trial among people who had never given birth, those who received the block reported pain scores roughly 40% lower during IUD placement compared to those who received no block.6PubMed Central. Paracervical Block for Intrauterine Device Placement Among Nulliparous Women: A Randomized Controlled Trial The benefit extended beyond the insertion moment itself, with lower scores during uterine sounding and even five minutes afterward. A systematic review and meta-analysis of multiple randomized trials confirmed that paracervical block reduced pain across several procedural steps and that overall patient satisfaction was markedly higher in the block group compared to controls.7Middle East Fertility Society Journal. Paracervical block for reducing pain during intrauterine device placement: a systematic review and meta-analysis of randomized controlled trials A network meta-analysis comparing multiple approaches ranked paracervical lidocaine as the most effective option for reducing pain during IUD insertion.8North American Proceedings in Gynecology and Obstetrics – Supplemental. Pharmacologic Pain Management for IUD Insertion: A Systematic Review and Network Meta-Analysis
The catch is that the injection itself can sting. But even accounting for that discomfort, patients who received the block rated their overall procedural experience as less painful than those who went without it.9PubMed Central. Paracervical Block for Intrauterine Device Placement Among Nulliparous Women: A Randomized Controlled Trial
Lidocaine Spray
Topical lidocaine spray applied to the cervix sounds like a simpler alternative, but the evidence is contradictory. One double-blind trial found that a 10% lidocaine spray dramatically lowered pain during IUD insertion compared to placebo.10PubMed. Lidocaine 10% spray to the cervix reduces pain during intrauterine device insertion: a double-blind randomised controlled trial However, another randomized trial found essentially no difference at all between lidocaine spray and placebo, with nearly identical average pain scores in both groups.11PubMed Central. The role of lidocaine spray in reducing pain during intrauterine device insertion The conflicting results likely come down to differences in spray concentration, application timing, and how long the anesthetic was allowed to take effect before the procedure began. For now, topical spray is a gamble compared to the more reliable paracervical block.
Misoprostol
Misoprostol is a medication sometimes given before cervical procedures to soften and slightly dilate the cervix. There is measurable evidence that it does soften cervical tissue.12PubMed Central. Objective Assessment of Cervical Stiffness after Administration of Misoprostol for Intrauterine Contraceptive Insertion But a large Cochrane review concluded that for routine IUD placement, misoprostol compared to placebo makes little to no difference to pain or to placement success. The one exception was in people who had recently had a failed insertion attempt, where misoprostol did improve the chances of getting the device placed successfully. Meanwhile, misoprostol consistently caused its own side effects, including pre-procedure cramping and diarrhea.13PubMed Central. Misoprostol for intrauterine device placement The takeaway is that for a first-time, routine insertion, misoprostol adds discomfort without helping much.
In premenopausal people who have never given birth and are undergoing hysteroscopy (a different procedure that also passes through the cervix), misoprostol did reduce pain during the scope’s introduction compared to placebo. But it also caused significantly more intestinal side effects.14PubMed Central / BJOG. Misoprostol for cervical priming prior to hysteroscopy in postmenopausal and premenopausal nulliparous women; a multicentre randomised placebo controlled trial So its usefulness depends on the procedure and the population.
Non-Drug Approaches
A systematic review of non-pharmacologic techniques found that only a handful showed clear pain reduction. Two approaches stood out in randomized trials: a breathing technique where the patient inhales deeply and holds their breath during insertion (a Valsalva-type maneuver), and acupuncture.15BMJ Sexual & Reproductive Health. Non-pharmacologic techniques for interval intrauterine device placement: a systematic review These are relatively low-cost options that could complement medication, though neither has been studied as widely as pharmacologic methods.
When Insertion Fails or Gets Complicated
Most cervical insertions are straightforward, but not all of them. Cervical stenosis, where the canal is unusually narrow or scarred shut, is one of the more common reasons an IUD placement can’t be completed. A study of ultrasound-guided IUD insertions found that cervical stenosis and patient discomfort were among the leading causes of failed procedures.16PubMed. Sonographically guided insertion of intrauterine device: Indications and results Stenosis is more common after menopause, after certain cervical surgeries, and in people who have never been pregnant.
A more serious but rare complication is uterine perforation, where the instrument passes through the wall of the uterus. Provider inexperience and a lack of scheduled follow-up visits after insertion have been identified as factors that increase perforation risk.17PubMed Central. Risk factors of uterine perforation when using contraceptive intrauterine devices While perforation gets a lot of fearful attention, it remains uncommon. The risk is on the order of about 1 in 1,000 insertions in most large datasets.
Another concern people sometimes raise is infection. A study that cultured bacteria from removed IUDs found that the organisms present were common vaginal bacteria that do not account for pelvic inflammatory disease, and no PID cases were recorded during follow-up.18PubMed. Bacteriological cultures of removed intrauterine devices and pelvic inflammatory disease The current understanding is that infection risk is very low and is concentrated in the first few weeks after insertion, mostly among people who already had a sexually transmitted infection at the time of placement rather than because of the device itself.
Cervical shock is a dramatic but rare reaction where stimulation of the cervix triggers a sudden drop in heart rate and blood pressure. It can happen during IUD insertion, manual removal of tissue from the cervix, or other cervical manipulation.19PubMed Central. Cervical vasovagal shock: A rare complication of incomplete abortion case report If it occurs, it usually resolves quickly once the stimulation stops, but it is one reason providers monitor patients during and briefly after the procedure.
Cervical Insertion in Labor Induction
Outside of contraception, one of the most common cervical insertion procedures happens in obstetrics. When labor needs to be induced and the cervix isn’t ready, a Foley catheter can be passed through the cervical canal and inflated with saline on the other side. The gentle mechanical pressure encourages the cervix to soften and dilate over several hours. A prospective study of 320 women found that about half achieved a favorable cervix or went into labor within 24 hours, and two-thirds delivered within 48 hours. Serious adverse events were rare and mild.20PubMed. Cervical ripening with Foley catheter balloon: A prospective cohort of 320 women
Double-balloon catheters, designed specifically for this purpose, are sometimes used as an alternative. But a systematic review comparing double-balloon to single-balloon (standard Foley) catheters found no meaningful differences in cesarean rates, time to delivery, or how much the cervix dilated. The Foley catheter is cheaper, more widely available, and has a longer track record, making it the more practical choice.21PubMed. Double-balloon versus single-balloon catheter for cervical ripening and labor induction: A systematic review and meta-analysis One trial in the review did find that pain during ripening was higher with the double balloon, though pain during the actual insertion was inconsistent between studies.
Cervical Insertion During Fertility Treatment
Embryo transfer during IVF is another procedure that passes through the cervix, and here the stakes are particularly high because the quality of the insertion directly affects whether pregnancy occurs. A straightforward transfer, where the catheter passes through the cervical canal without difficulty, produces significantly better outcomes. One study found that implantation rates were roughly 22% in the easy-transfer group compared to about 12% when the transfer was difficult, and pregnancy rates followed a similar pattern.22PubMed Central. Comparison of Easy and Difficult Embryo Transfer Outcomes in In Vitro Fertilization Cycles
A systematic review and meta-analysis across multiple studies confirmed the trend: difficult transfers reduced the odds of pregnancy by about 30% and the odds of live birth by about a third.23Scientific Reports. The impact of difficult embryo transfer on the success of IVF: a systematic review and meta-analysis The reasons likely include disruption to the uterine lining, introduction of cervical mucus or bacteria into the cavity, and triggering of contractions from excessive manipulation. When providers need to use extra tools or multiple attempts to navigate the cervical canal, the chances of success drop. Blood on the catheter tip after a difficult transfer is another marker linked to lower pregnancy rates.24PubMed Central. Difficult Embryo Transfer: A Systematic Review
This is one reason fertility clinics often do a practice or “mock” transfer before the real one, mapping the cervical canal’s angle and depth so the actual transfer goes as smoothly as possible.
What the Cervix Is Actually Like as a Tissue
Understanding why some cervical insertions are easier than others comes down partly to the tissue itself. The cervix is mostly made of connective tissue, not muscle, and it behaves in a nonlinear, time-dependent way under pressure. Mechanical testing has shown that cervical tissue from non-pregnant individuals is significantly stiffer than tissue from pregnant individuals, in both tension and compression.25PubMed. Mechanical and biochemical properties of human cervical tissue This helps explain why insertions tend to be more difficult in people who have never been pregnant: their cervix simply hasn’t undergone the softening and remodeling that pregnancy induces.
Computer simulations of cervical dilation have compared different dilation methods and found that traditional rigid dilators (like Hegar dilators, which are tapered metal rods) create higher stress concentrations in the tissue than gentler hydraulic devices.26PubMed Central. Computer simulation of cervical tissue response to a hydraulic dilator device This research supports the broader move toward instruments that spread force more evenly across the cervix rather than concentrating it at a single point.
Newer Instruments Designed to Reduce Pain
One of the more interesting recent developments is the suction cervical stabilizer, a device that holds the cervix in place using gentle vacuum rather than the traditional toothed tenaculum clamp. A randomized controlled trial compared the suction device to a standard tenaculum during IUD insertion and found substantially lower pain scores at the cervix-grasping step, with the biggest benefit seen in people who had never given birth. The suction device also caused less bleeding.27PubMed. Safety and efficacy of a suction cervical stabilizer for intrauterine contraceptive device insertion: Results from a randomized, controlled study
A larger post-marketing study of over 1,000 IUD insertions confirmed the pattern. Average pain scores were lower when the suction stabilizer was used alone compared to cases where a tenaculum had to be brought in as backup. Cervical bleeding requiring management was also less frequent with suction alone.28PubMed Central. Safety and efficacy of a suction cervical stabilizer for IUD insertion: Results from a multicenter post‐marketing study This doesn’t eliminate pain during the actual insertion through the canal, but it meaningfully reduces one of the most uncomfortable steps. It also cuts down on the small amount of bleeding and bruising that the tenaculum can cause.
Asking for Pain Management Before Your Procedure
If you have an upcoming procedure that involves cervical insertion, you are well within your rights to ask about pain management options beforehand. The evidence supports requesting a paracervical block, particularly if you have never given birth vaginally. If your provider doesn’t routinely offer one, the research gives you grounds to have that conversation. A practical review noted that few studies have provided definitive conclusions on pain prevention for IUD placement, and that many recommendations still rely on non-evidence-based interventions.29BMJ Sexual & Reproductive Health. Practical advice for avoidance of pain associated with insertion of intrauterine contraceptives That gap means you may need to advocate for yourself.
Beyond medication, some things you can do on your own include timing the procedure to fall during the first half of your menstrual cycle (when the cervix tends to be slightly more open), practicing slow breathing techniques, and addressing anxiety directly. Given how strongly pre-procedure worry correlates with pain during the procedure, anything that genuinely calms your nerves is likely to help. Some clinics now offer music, guided breathing, or the option to have a support person present. None of these replaces an anesthetic for a truly painful insertion, but they can shift the overall experience enough to matter.