Preventing Pregnancy And STDs With FemCap
This interesting medical study highlights how the thinner layers of skin on the cervix need protection in order to reduce the probability of STDs being passed. The FemCap can help with this protection but remember it offers no guarentee of protecting against STDs, for that, use a condom or abstain!
Preventing Pregnancy and Sexually Transmitted Disease Infections, by Novel and Unique Approach
Alfred A. Shihata, MD, Scripps Institution of Medicine and Science, San Diego, CA, USA
Steven A. Brody, MD, PhD, University Of California School Of Medicine, Department Endocrinology, La Jolla, CA, USA
To provide women with an alternative to the condom for the dual prevention of pregnancy and sexually transmitted diseases.
Background: Women are the fastest growing demographic of STI/HIV infections worldwide. Ulcerative and non-ulcerative STIs enhance the transmission of HIV. Though the condom offers the best prevention against STI/ HIV, the condom ¡s not an option for many women. Thus far the condom, diaphragm and microbicides have failed to impact the spread of these infections. As these oíd and familiar methods repeatedly fail, we strongly believe that STI/HIV prevention must be tackled from a different angle. Therefore, we urgently need an alternative to the condom that is covert, woman-controlled, and delivers microbicide on the vaginal side. The FemCap is a new cervical barrier contraceptive device that is available in all European countries and US. The FemCap is designed to shield the cervix,
(site of CCR-5 and CXCR-4 receptors), from microbicide irritation, STI/HIV invasión and sperm penetration. The FemCap delivers the microbicide on the vaginal side, to encounter sperm and STI/HIV organisms upon deposition into
the vagina and before they enter the cervix.
Design and Methods:
Ten women applied a microbicide mixed with Gentian violet dye onto the vaginal side of the FemCap, and inserted it vaginally. The cervix and vagina were photographed before, during, and 6 hours after removal of the FemCap.
The bulk of the microbicide/dye carne out upon removal of the FemCap without staining the cervix, while the vaginal walls were lightly stained with the dye.
The FemCap protected the cervix from exposure to the dye. The FemCap/microbicide combination can prevent pregnancy and may provide women with an alternative to the condom that is covert, woman-controlled and coitally- independent. The FemCap/microbicide combination warrant further comparative head-to head research with the condom to prove this concept.
The Rationale for the Dual Strategy: The FemCap and Microbicide
Anatomy: The vaginal mucosa ¡s comprised of múltiple layers of stratified squamous epithelium, and have many rugae, sufficient to expand several hundred folds during delivery. Therefore, ¡nserted microbicide gel or cream cannot fully cover the entire corrugated mucous membrane of the vagina. This is in stark contrast to the endocervical canal of the cervix which is covered by single layer of very vascular, friable columnar epithelium and heavy concentration of chemokine co-receptors CCR-5 and CXCR-4, for the HIV virus.
Physiology. The vaginal PH is acidic which inhospitable to the HIV virus and other pathogenic microorganisms. The Vagina is a conduit that expels its contents in both directions, upwards through the cervical opening to the uterus, and downward to the outside. Consequently, any insertad gel will soon be expelled outside. MRI studies have shown that the bulk of all vaginal gels leak to the outside in a short time, resulting in poor coverage and retention of the microbicide. The PH of the cervix is neutral, which is compatible with microorganisms survival and even colonization of Chlamydia and Gonorrhea. The continuous exposure of the cervix 24 hours, 7 days a week, with any microbicide, no matter how safe it is, will lead to maceration of the cervix, making it more vulnerable to STIs/HIV invasión. This applies to any vaginal lubricants such as KY Jelly or Replens and even to water.
Immunology: The cervical canal and transformation zone is the main portal of entry for HIV. This epithelium has a very heavy concentration of chemokine co-receptors CCR-5 and CXCR-4. The HIV virus fuses with tríese receptors in order to enter the CD4 cells. Over time, the slightest irritation will mobilizes the immune cells to the cervix, which become the primary target for HIV virus invasión.
The HIV virus:
• Fragüe and easy to kill in-vitro by almost any microbicidal agent, such as soap and water, lemon juice, and Nonoxynol-9.
• Unlike other viruses and bacteria it invades and destroys immune cells. The hiqher the number of immune cells. the higher the risk of HIV transmission. adding "fuel to the fire." Ulcerative and non-ulcerative_STIs enhance HIV invasión.
• HIV invades the body through any bleeding surface such as bleeding cervix, endometrium or herpetic ulcers.
• The virus of an infected patient is present in all body fluids, with heavier concentration in the semen.
•The vast majority of transmission occurs through heterosexual intercourse, from men to women.
The Ideal Microbicide:
A) Should preserve the vaginal ecology,
B) Strong enough to kill sperm and STIs/HIV organisms before they enter the cervix.
C) Gentle enough not to disrupt the cervicovaginal epithelium, or provoke an immune response that enhances the HIV invasión.
D) It should be retained ¡n the vagina for at léase 24 hours, to minimize repeated application.
E) Should not contact the cervix.
Lesson learned from clinical trials:
N-9 and Cellulose Sulphate were effective against the HIV virus, in-vitro yet they increased the HIV transmission in clinical triáis. Carraguard, Buffergel and PRO 2000 were safe but not effective. The diaphragm and vaginal lubricant Replens failed to prevent HIV invasión.( See MIRA study) This is because the continuous exposure of the cervix to Replens, 24 hours/7days per week, induced cervical irritation due to its hyperosmolilty, and thus eliminated or neutralized the protective effect of the diaphragm.
Until the ideal microbicide is found. we should use a delivery svstem for the microbicide to achieve the following goals:
1-To provide women with an alternative to the condom that is covert, female-controlled and coitally-independent.
2-To kill sperm and STIs/HIV organisms upon deposition in the vagina and before they enter the cervix.
3-To shield the cervix and uterus from sperm penetration, STIs/HIV invasión, and microbicide irritation.
4-To enhance the safety and efficacy of microbicides by preventing its contact with the cervicovaginal mucosa.
The dual strategy of the FemCap/Microbicide combination can prevent pregnancy and may fulfill the above objectives.