Prentif and its sado-masochist use

A 25 mm Prentif cervical cap and hard shank Gaynors

The Prentif Cavity Rim cervical cap: The Prentif, approved by the FDA in the late 80s for use in the U.S as a contraceptive barrier, came in four sizes: 22, 25, 28, and 31mm, which were the internal dimensions of the base of the dome. I take a 25mm and bought several before the manufacturer, Lamberts, stopped making them in about 2005 and I continue to find wearing them fun. When forced down over a smooth walled cervix the cavity in the rim develops a strong suction that holds it securely on the cervix. Once the cap is properly positioned the tab on the shoulder of the rim (seen at about one-o’clock in the photo above) is used to turn the cap a full turn while pressing on the dome to ‘screw it down’ on the cervix.

When Prentif is used as intended, for contraception, it’s important to remember that the tab should be positioned behind the cervix after the turn to screw the cap down so that the edges aren’t hit by a thrusting penis. The Prentif, for those fortunate enough to have serviceable ones, can be worn continuously for 48 hours w/o using any additional spermicide. Prentif is as effective, about 94%, as a diaphragm for nulliparous women. For parous women cervical changes make the Prentif only about 85% effective. I think the biggest problem with the Prentif cap was that there was not size smaller than the 22mm, say about 19mm as a great many women who wanted to wear a Prentif had cervixes too small to be properly fitted.

Dimensions and fit: The 25mm cap is 4cm tall and when forced on to a typical 3 cm long cervix there is about a 2cm space between the tip of the cervix and the inside top of the dome. This space is usually partially filled with a spermicide as back-up contraception so if the cap displaces sperm will be immobilized by the spermicide in the dome. When the cap is suctioning well the vacuum in the domes of the 25 through 31 mm sizes will cause the top of the dome to dimple. The dome of the 22mm is too stiff to dimple under vacuum. A sign that the cap is too old and the latex is getting stiff is if the dome of 25mm and larger caps becomes permanently dimpled.

When I wore a Prentif as my primary method in the late 90s my fit was so tight that I never used spermicide in the dome and had to pry it off after a 48 hour wearing interval. If a woman wearing a 22mm Prentif was fertile and she wore the cap for the full 48 hour interval there was a possibility that the dome could fill with fertile cervical mucus and then when hit by a thrusting penis it could ‘float off’ her cervix. Even though I wear a 25mm I thought it was a good idea when fertile to wear Prentif for only 24 hours to make sure the dome wasn’t full and I didn’t have an accident.

Sado-Masochism and Prentif: The outer diameter of a 25mm cap is about 4cm at the base of the cap, thus increasing the diameter at the base of the cervix by about 1.5cm when the cap is properly positioned. The increase in length of the cervix by as much as 2cm (discussed above) and its diameter by 1.5cm increases the cervix ‘target’ size. This is a condition seemingly appreciated only by a few Prentif wearers and our partners in the BDSM community who enjoy cervical or penile glans battering (both of which are acquired tastes) if the man is not quite long enough to reach the cervix unaided.

Cervix battering: For cervix battering of a masochist partner most men don’t seem to mind thrusting into the Prentifs soft dome. The base containing the cavity rim is a bit stiffer, but if the shoulder tab is behind the cervix so it isn’t hit my partners say it’s not uncomfortable and often overlooked when the woman gasps or moans when he hits the dome straight on. If a nulliparous woman’s cervix is smooth and the cap correctly sized and screwed down tight a thrusting penis shouldn’t dislodge it.

Glans battering: For glans battering the shoulder tab is rotated so it faces the anterior wall of the vagina. That way the man is quite likely to hit the tab with some frequency. When glans battering is intended it’s best to have the man wear a well fitting cock ring to prevent him going flaccid when he hits the tab. Of course a man in a cock ring limits the duration of safe play to about 20 minutes. Very few male masochists can repeatedly hit the shoulder tab of a Prentif and retain an erection w/o wearing a cock ring. I’ve found that astride where I control the depth and direction of penetration or missionary where I’m wearing bedshoes to increase the range of my pelvic thrusts, are the best positions for battering a man’s glans.

Escorts, caution and the Prentif: For the few escorts who specialize in male penile sadism it’s a premium service. Using a Prentif that way takes experience (there are no classes) so she knows how to hit his glans a glancing blow with the tab to minimize the number of solid hits she takes to her cervix while causing him the most pain. That’s because uterine prolapse where the uterus drops into the vagina, is a common problem experienced by escorts who specialize in clients paying for rough cervical contact. Uterine prolapse in an escort is usually the end of her career since even with surgery afterward she is rarely the same.

In my teens it took me getting only a few solid blows to my cervix to learn to adjust my hips and pelvis to take glancing blows that stimulate my libido while minimizing the possibility of damage to the muscles and ligaments holding my uterus in place. Of course working out with Ben Wa balls as we all do is very good exercise to strengthen the pelvic muscles to avoid a prolapse.

Porn and the Prentif cap

A pair of 22mm (ID) latex Prentif cavity rim cervical caps

A rubberist’s delight: One of my fave stallions is a well endowed rubberist who delights in being able to thrust into my cervix, even when he penetrates me from behind. What really lights his fuse though is if I wear a Prentif cap sucking on my cervix so he can thrust into the soft latex dome. I wear a 25mm Prentif so the top of the dome dimples, collapses a bit, under vacuum, so that if he hits the dimple he knows he is right on target and thrusting into the soft stretchy latex and him ‘double tapping’ the dome and then the tip of my cervix under it gets him off very quickly.

The Prentif and the porn industry: Our clinic is one of the very few that still fits Prentif caps. That’s because Lamberts (Dalston) Ltd stopped making them at least four years ago and our clinic having a large Prentif user base bought up all the Prentif stock they could, much of it at a deep discount. Recently porn producers have discovered cervical barriers as a “new” fetish to be exploited. Since very few men younger that 60 have heard of diaphragms or cervical caps a Prentif used as protection by a porn actress in a video has become a ‘HOT’ retro scene guaranteed to increase demand for any vid in which one is used. Any producer who has his actress take fifteen minutes to languidly insert her Prentif as foreplay while her boyfriend/client is watching or has it pulled out by her attacker during her rape or has her lover eat her cervical mucus out of the dome is guaranteed a best seller.

Then too here is the ‘Geezer factor’ in niche-market porn especially in Europe where the Prentif was far more popular in the 50s than diaphragms and I’m told by the marketers that men of a certain age and style remember it fondly even though they now need performance enhancing meds to participate. Another advantage of a cap or diaphragm being used in porn is that unlike birth control hormones it is a physical object that can be inserted during a tender moment for protection or roughly pulled from the heroine or victim’s vagina during a rape and shoved into her mouth to emphasize the danger she is in. And for those into asphyxia a Prentif can be shoved down the woman’s throat as a very dangerous form of breath play because she can easily suffocate while her attacker is concentrating on planting his seed in her belly. With the increased interest in cervical barriers for use in porn – a lot of the resurgence has been because of the ‘Mad Men’ effect of retro TV shows that got the country longing for what seems a simpler time – our clinic is seeing a substantial increase in requests to fit Prentif caps.

Porn and poor cervical barrier technique: Porn actresses don’t rely on the effectiveness of a diaphragm or cap for contraceptive protection. Many of them have been sterilized or have had IUDs inserted so that an unplanned pregnancy from on-cam intercourse is very unlikely. That makes it far less important that most porn actresses be correctly fitted with a barrier that will remain securely in place through multiple acts of intercourse and for at least six hours afterward. All they need is one that won’t give them a UTI and won’t fall out while they are on-cam. Nor do they need to adhere to correct barrier insertion technique during a video production and that can leave the men and women watching the video with the wrong impression as to how to properly protect a woman using a cervical barrier.

The problem comes from the way the porn actresses are playing with their barriers and appear to become aroused long before insertion. As returning readers know a woman needs to insert her cervical barrier BEFORE she becomes aroused! That’s because during arousal the vagina lengthens (tents) as the uterus and thus the cervix is drawn up and out of the way of a thrusting penis. A vagina that is fully tented can make it very difficult or impossible to place a cervical barrier correctly over the cervix and therefore makes an unplanned pregnancy far more likely.

I’ve tried talking to several of the major producers of cervical barrier porn and they just laugh and say they are interested in getting their audience as hot as fast as possible and a porn-princess moaning and rubbing her barrier over her engorged labia wet with natural lube while she moans and writhes in ecstasy as she plays with herself is a critical part of the production and there won’t be any changes to correctly depict proper insertion technique. I suspected that was the answer I was going to get, but it was worth a try. It does make it more difficult to get vanilla women wanting to portray Magna Cum Loudly or other porn princesses to use their barriers correctly if they will need them for contraception and not just as a sex toy.

I’m trying to steer the porn actresses and their costumers toward diaphragms or FemCap and away from Prentif because the porn industry is not interested in contraception and as I mentioned above Prentif is now a device in short supply and the remaining caps should be used for women who intend to use them correctly for contraception and as gas-guards for upper reproductive tract protection during dive-sex.

Christmas break barrier fittings: At St Lucy’s it’s the end of Fall semester and we are finishing the fit checks – and replacements where necessary - of the cervical barriers the students wear before they go home or travel on Christmas break. While many of the upper form students were sexually active before arriving at St Lucy’s none had enough experience to have caused their vagina’s to stretch appreciably. While they have grown in the months they have been immersed in a strict ballet and pelvic training regimen the pelvic floor muscles have toned considerably making the vagina deeper and tighter. Fit checks are important before the increased use of cervical protection while away from the school’s sexual health support system. It’s also time for an ultrasound to verify the proper placement of students IUDs and for full STI panels to make certain the students are all healthy before sending them back to their families

The students in my Advanced Sexual Techniques class use their barriers as gas-guards for dive-sex while others on hormones use them for flow control for vanilla sex during their pill-periods or if they have a stringless IUD inserted. Stringless GyneFix IUD implants have become much more popular this year because they allow GyneFix users to safely wear a diaphragm or FemCap as a gas-guard during dive-sex. For anyone wondering the smallest Prentif, with an inner diameter of 22 mm, is too large for most teens to wear but they can wear a 22 mm FemCap because the FemCap seals against the walls of the vagina and not the cervix. So Prentif caps are left for the use of experienced adult women.

UNLV’s Fall semester also ends on December 17th and many of the sorority girls I know have had our clinic check the fit of their diaphragms and will be leaving mid week rather than on that Saturday so there has been a surge in barrier fit checks and some requests for STI panels for them as well. The students come to us to avoid having these items show up on their UNLV Student Health statements that are sent to their parents.

Checking Slit-kits: Before traveling for the holidays is also the time to check and restock everyone’s skit kits to ensure condoms, spermicide, antibiotics and emergency contraception pills are all fully stocked and in-date. There are two effective EC specific pills:

Plan B One-Step (a single pill containing 1.5 mg of the progestin levonorgestrel) which is effective for up to 72 hours, three days, after unprotected sex or a contraceptive failure. Plan Bs effectiveness decreases the longer after the event it’s taken so it should be taken as soon after the event of concern as possible. Women on oral contraceptives may continue taking them on their normal schedule after taking Plan B. In the U.S Plan B is available to women 17 years of age or older behind the counter w/o a prescription.

The second and newer pill is available in the U.S. as ella and in Europe as ellaOne (a single pill containing 30 mg of ulipristal acetate, a progesterone receptor modulator) which is effective for up to five days after the event of concern. Women on hormonal contraceptives should not rely on the effectiveness of their pills, but use a reliable barrier method of contraception after using ella, for any subsequent acts of intercourse that occur in that same menstrual cycle.

For EC our clinic now recommends ella, because of its longer effectiveness interval and at St Lucy’s its cost is covered by the student’s Student Health policy.

The Prentif as a bondage device

My 25mm Prentif turned inside out to show the cavity rim that grips the cervix

Rubber-Masters and the Prentif cap: I have received several enquiries already from Rubber Masters interested in introducing the Prentif into a submissives heavy latex encasement wardrobe. I have to say that is a diabolical idea to use a woman’s contraception and over pressure protection as bondage device to put her further under her master’s control. While use of the Prentif was very popular among sophisticated European women in the mid 20th centaury as a convenient and effective method of birth control it was rarely used as a method of subjugation. These days with the rediscovery of the Prentif by the latex fetish community, encasement of a woman’s cervix in heavy rubber seems to be a turn on not only for birth control device fetishists but for heavy rubber encasement fetishists as well. The soft thick rubber of the Prentif and the grip of the vacuum in both the rim and dome of the cap on such a feminine part of a submissive make Prentif particularly well suited for use in total heavy rubber encasement of beautiful woman of child bearing age. For women not used to wearing a Prentif the grip of the rim and the vacuum in the dome can cause some cramping which Rubber Masters seem to like. I think it is a psychological thing for a heavy rubber encasement fetish guy because he can’t really see his slaves heavy rubber encased cervix w/o using a speculum, but he can feel it with his fingers if she pushes her cervix down.

Fitting, insertion and care of a Prentif: There are four sizes, based on the inside diameter, of Prentif caps: 22 mm, 25 mm, 28 mm, and 31 mm. To ensure a proper fit the cervix should be closely inspected by the woman’s fitter to determine that the cervix is smooth and symmetrical so as not to interfere with the cavity in the rim sealing against the wall all the way around the cervix. It is important to insert a cavity rim cap, either Prentif or Oves, before becoming aroused. After a woman becomes aroused it may be impossible to insert it correctly because the vagina lengthens (tents) during arousal and the pelvis engorges with blood making correct placement and suction on the cervix very difficult to obtain. Before inserting a cervical cap the woman should wash her hands and have short nails or wear latex exam gloves so she doesn’t scratch herself. Then compress the rim and while spreading her labia with the fingers of one hand push the compressed rim into the vagina. Once behind the pubic bone push it up and over the cervix. This can take a bit of getting used to while determining the best angle to use and care must be taken because if turned the cap can suction onto the wall of the vagina rather than on the base of the cervix. Once the cap is in place and the dome dimples the wearer should sweep a finger all the way around the dome to check that the cap is correctly covering the cervix.

To test for a good seal the woman should insert the cap, wait 15 minutes, remove the cap and then immediately feel for the raised rim tissue – that was pulled into the rim cavity - to ensure that there is raised tissue the full 360 degrees around the cervix. If there is raised tissue all the way around the cervix after 15 minutes of wear that means the cap is a good fit and it is sealing well. Also on all but the 22 mm size, the top of the dome will dimple from the vacuum in the dome if the cap is a good fit. A 22 mm will not dimple because the dome is too small and stiff.

To clean a Prentif it should be turned inside out and the cavity cleaned carefully with a toothbrush and warm mild oil free soap and water to ensure it is free of mucus, rinsed well and then let air dry. A Prentif should not be exposed to cold weather as the latex will harden and shatter and of course oils will cause the natural rubber to deteriorate rapidly so only water based lubes should be used with a Prentif. To visually inspect for latex aging; the first sign is that the latex will become stiffer, gives less and the domes of the larger caps will remain dimpled after the vacuum is released. Then look for cracking around the dome to rim interface while the Prentif is turned inside out for cleaning. This will reveal any latex aging. The effective life of a Prentif will depend on the user (use frequency and vaginal environment) and can be as short as 2 years and as long as 10 years. I take good care of my 25 mm Prentif and though it is no longer my primary method I use it occasionally for play. It is 7 years old and still develops a wicked vacuum so I have to pry it off my cervix and shows no sign of latex fatigue. A Prentif cap can be worn safely for at least 48 hours then removed, cleaned and immediately reinserted. If spermicide is used the dome should be no more than a third full, more could cause the spermicide to be forced into the rim cavity and break the suction. And as I’ve mentioned women with excellent fitting Prentif caps can safely wear them dry.

Ballerina birth control before the pill

The Prentif cavity rim cervical cap

Ballet boots and Prentif: In addition to UDP (a premium service) at the ranch we offer fantasy ballet encounters with our ballet dancers from Central Europe in standard studio, dressing room or salon settings. Or, we will create a custom setting for the encounter if the client can stand the cost. On request the girls will wear some of the older styles of contraceptive barriers and the Prentif cap is a particular favorite of men who want to recreate the 1930s – 1950s milieu right down to the exact contraception that was widely used by dancers in Europe in the years before the pill became available. Ballet boots that button rather than lace up never really caught on, but the nightclubs, especially in Germany and Austria – between the wars - were deep into ballet related fetishes. The Viennese fetish boot (circa 1900), which sported a heel that was actually longer than the sole of the shoe, thus making standing and/or walking impossible was the ancester of the ballet boot. A creative and enteerprising balletgirl shortened the heels of her Viennese fetish boots and a new style was born that only became resurgent again in the 1980s.

Fetish boots and shoes: A client can choose what fetish footwear his partner will wear. Ballet boots are available in ankle, calf, knee or thigh lengths that the client can help her lace up. In addition, for men with a pointe shoe sole design fetish the following makers pointes are available: Freed, Capezio, Bloch, Gamba, Chacott, Grishko, Russian Pointe, Merlet and Schachtner and pointes from other makers can be worn with two weeks advance notice. At her client’s request his partner will wear a particular maker’s shoes and style so the men can admire the sole patterns on their pointes, or even suck on the platforms, while she is on her back with her feet in the air taking his thrusts against the soft thick latex dome of her Prentif..

In the European cabarets where fetish was king between the great wars abortions were common for unplanned pregnancies that resulted from failed barrier contraceptive methods when oil based lubes were routinely used with latex barriers by unsuspecting women which caused frequent failures especially for new users who hadn’t been properly warned. Of course there were also the tricks where a dancer would arrange for her rivals birth control to fail by slipping punctured condoms into the rivals purse or dance bag when it was known she would be entertaining her lover for a quickie and unlikely to be as careful as she should. The recovery time from the physical, and occasionally mental, effects of an abortion guaranteed that the pregnant woman would be off stage for weeks as she regained her strength and confidence giving a rival an opportunity to steal her roles. We still see some of that today with school girls exchanging a rival’s pills with a dummy pack causing her to get her period or knocked up. Of course with Plan B and Mifeprex that sort of thing is quickly resolved today as little more than a minor inconvenience with very little worry.

Soft rubber caps: In the early 1900s there were custom made metal cervical caps of silver or gold, but those were very expensive and rarely used by performers, unless paid for by a wealthy lover. The answer to failed condoms for most women who wanted to control their own fertility was to wear a latex cervical cap that was rugged enough that it wouldn’t fail immediately even if it was used with Vaseline or another petroleum product. That way the woman could check for leaks, apply spermicide and insert in privacy where no one could tamper with her cap. And, if an oil based lube was used the Prentif while beginning to experience damage wouldn’t leak during the encounter nor while providing at least eight hours of protection afterward while her partner’s sperm died in her belly. The soft rubber dome of the Prentif also provides sensation for a man of average size who wants to thrust into his partner’s cervix while providing her with a modest amount of thrust buffering by distributing the energy of his thrusts equally around the walls at the base of the cervix.

Wearing a cavity rim cap dry: Actually, a well fitting Prentif, just like a well fitting Oves cap can be worn ‘dry’, that is w/o spermicide in the dome. Of course that means that if it should dislodge there is no backup contraception, but with a well fitting Prentif or Oves the likelihood of it dislodging is very remote, unless worn during the woman’s period when it could fill with her menstrual flow and ‘float’ off her cervix. A FemCap, the only cap generally available in the U.S. at the moment, can not be safely worn w/o using spermicide in the dome and also in the channel on the outside of the cap at the base of the brim. After a few cycles, when I was sure of its excellent fit, I wore my Prentif dry and have done the same with my Oves caps (once I became confident of their strong suction on my cervix) for more than seven years, that’s ninety-three cycles, with no pregnancy scares. And for someone who is as sexually active as I am that is an amazing tribute to the tiny bit of .25mm thick transparent silicone rubber that keeps me well protected by sucking on my cervix. Occasionally a casual lover will want me to give him one of my Oves caps, but they are not souvenirs. I think they are such an intimate part of me that I burn my old Oves caps along with my dead pointe shoes so that nothing so intimate as my cervical protection is ever given away.

Ballerina’s with children: From the ascendancy of women in classical ballet through the 1940s when personal discipline and sacrifice for the art of classical ballet was expected and enforced – by ballet management – women did not have children and expect to continue as a ballet dancer. Stars as famous as the British ballerina Margot Fonteyn, after an unintended pregnancy and abortion, had her tubes tied and managed to hush it up to continue dancing. Today, ballet dancers, if they are good enough so they are not easily replaced by management, can have children and a career as well. Darcey Bussell (British Royal Ballet retired), Julie Kent (ABT) and Alessandra Ferri (ABT retired) to name a few all had their families in their 30s after their careers as ballet Principals were well established and returned to dancing afterward. Cyd Charisse the lovely long legged MGM ballet dancer was offered the female lead in An American in Paris if she would have an abortion. She refused to abort her son with her husband Tony Martin and Leslie Caron took her place beside Gene Kelly in the 1951 musical. We’ve come a long way baby! Sigh!