Typically, spermicides function by providing a physical barrier to sperm penetration and a chemical spermicidal action. The active ingredient is nonoxynol-9 or octoxynol-9. Although these are spermicidal, they do not provide STD protection. Ideally, spermicides must be deposited high in the vagina in contact with the cervix shortly before intercourse. Their duration of maximal efectiveness is usually no more than 1 hour, and thereafter, they must be reinserted before repeat intercourse. Douching is avoided for at least 6 hours after coitus.
The Today contraceptive sponge is an over-the-counter, onesize-fits-all device. The nonoxynol-9-impregnated polyurethane disc is 2.5 cm thick and 5.5 cm wide and has a dimple on one side and satin loop on the other (Fig. 38-8). The sponge can be inserted up to 24 hours prior to intercourse, and while in place, it provides contraception regardless of coital frequency. It should remain in place for 6 hours after intercourse. Pregnancy is prevented primarily by the spermicide nonoxynol-9 and to a lesser extent by covering the cervix and absorbing semen.
FIGURE 38-8 Today sponges. The sponge is moistened with tap water and gently squeezed to create light suds. It is then tioned with the dimple directly against the cervix. The fabric loop trails within the vagina and can be hooked with a finger to later extract the sponge.
TABLE 38-3. Methods Available for Use as Emergency Contraception
Pills per Number of
COC Pillsb,c aDoses taken 12 hours apart if multiple.
bOther COC brands with formulations identical to those above may also be used.
(Use of an antiemetic agent before taking the medication will lessen the risk of nausea, which is a common side effect.
COC = combination oral contraceptive; EE = ethinyl estradiol; IUD = intrauterine device; LNG = levonorgestrel; PRM = progesterone-receptor modulator.
Although the sponge is possibly more convenient than the diaphragm or condom, it is less efective than either (Kuyoh, 2013). Most common causes for method discontinuance are pregnancy, irritation, discomfort, or vaginitis (Beckman, 1989). Although toxic shock syndrome has been reported with the contraceptive sponge, it is rare, and evidence suggests that the sponge may actually limit production of the responsible staphylococcal exotoxin (Remington, 1987). Still, it is recommended that the sponge not be used during menses or the puerperium.
Following unprotected sexual intercourse, many women present for contraceptive care. Several emergency contraception (EC) regimens substantially lower the likelihood of an unwanted pregnancy when used correctly. Current methods include COCs, progestins, progesterone antagonists, and copper-containing IUDs (Table 38-3). Overall, the IUD is most efective, and ulipristal acetate is the most eicient oral regimen (American College of Obstetricians and Gynecologists, 2017a). Patients can obtain information regarding emergency contraception by calling 1-888-NOT-2-LATE or accessing The Emergency Contraception Website: http://not-2-late.com.