Effect of a single vaginal administration of levonorgestrel in Carraguard gel on the ovulatory process: a potential candidate for "dual protection" emergency contraception.
OBJECTIVE
The study was conducted to evaluate the effect of Carraguard vaginal gel containing 0.75 mg of levonorgestrel (CARRA/LNG gel) administered in a single dose at different stages of follicle development over subsequent follicle rupture and hormonal levels.


METHODS
Randomized, blinded, cross-over study comparing the effects of a single administration of CARRA/LNG gel or Carraguard (CARRA) gel. Twenty-four healthy women were enrolled in two centers. The gels were administered when the follicle had reached diameters of 12-14, 15-17 and > or =18 mm in eight women each. Volunteers were followed for one treatment, one washout cycle and a second treatment cycle. Follicle rupture or nonrupture was assessed by transvaginal ultrasound. Luteinizing hormone, estradiol and progesterone levels were measured daily for 5 days following treatment, and three times per week until menses.


RESULTS
No follicular rupture within the 5-day period following administration was observed in 74% and 30% of the CARRA/LNG and CARRA gel treatment cycles, respectively, while ovulation was documented in 4% and 61%, respectively. The overall proportion of cycles with lack of follicular rupture or ovulatory dysfunction (follicle rupture preceded by an inadequate LH surge) was 96% for CARRA/LNG and 39% in the CARRA gel cycles.


CONCLUSIONS
Single vaginal administration of 0.75 mg LNG in CARRA gel in the late follicular phase is effective for interfering with the ovulatory process.
Brache
Vivian
V
PROFAMILIA, Biomedical Research Department, P.O. Box 1053, Santo Domingo 10401, Dominican Republic. biomedica@codetel.net.do
Croxatto
Horacio
H
Sitruk-Ware
Regine
R
Maguire
Robin
R
Montero
Juan Carlos
JC
Kumar
Narender
N
Salvatierra
Ana Maria
AM
Tejada
Ana Sofia
AS
Cochón
Leila
L
Forcelledo
María Luisa
ML
Lahteenmaki
Pekka
P
Alvarez
Francisco
F
Faundes
Anibal
A
D000282:Administration, Intravaginal; D000328:Adult; D044363:Contraception, Postcoital; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D016912:Levonorgestrel / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D008597:Menstrual Cycle / Q000187:drug effects; D006080:Ovarian Follicle / Q000187:drug effects*; D010060:Ovulation / Q000187:drug effects*
D003271:Contraceptive Agents, Female; D016912:Levonorgestrel