Oj. D'Cruz et al., Contraceptive efficacy and safety studies of a novel microemulsion-based lipophilic vaginal spermicide, FERT STERIL, 75(1), 2001, pp. 115-124
Objective: To investigate the in vivo contraceptive potency and safety of a
novel microemulsion-based lipophilic vaginal spermicide.
Design: In vitro and in vivo spermicidal activity and safety of a submicron
-particle-size, lipophilic gel-microemulsion (GM-4).
Setting: Center for Advanced Preclinical Sciences at the Parker Hughes Inst
itute.
Patient(s): Nine male volunteer sperm donors.
Intervention(s): Motile human sperm in semen and medium were exposed to eig
ht GM-4 components or GM-4 formulation. Forty-eight ovulated NZW rabbits in
subgroups of 16 with or without intravaginal administration of GM-4 or non
oxynol-9 gel (N-9; Gynol II) were artificially inseminated and allowed to c
omplete pregnancy. Eleven rabbits were exposed to daily intravaginal applic
ation of GM-4 with and without N-9 for 10 consecutive days. Ten of 20 B6C3F
1 mice were given repetitive intravaginal application of GM-4 for 5 days/we
ek over 13 consecutive weeks.
Main Outcome Measure(s): The motility of human sperm treated with GM-4 comp
onents and GM-4. Term pregnancy in rabbits and histopathological grading of
rabbit Vaginal tissue for irritation. Evaluation of mice for survival, gro
wth, hematologic parameters, blood-chemistry profiles, absolute and relativ
e organ weights, and histopathology.
Result(s): The individual components of GM-4 lacked spermicidal activity in
human semen, whereas the GM-4 formulation containing all the eight pharmac
ological excipients exhibited potent spermicidal activity with rapid kineti
cs. GM-4 showed remarkable contraceptive activity in the rigorous rabbit mo
del. None of the 16 (0%) rabbits given GM-4 intravaginally before artificia
l insemination became pregnant. By contrast, 15 of 16 (93.7%) control rabbi
ts and 5 of 16 (31.2%) Gynol II-treated rabbits became pregnant and deliver
ed newborns. Thus, GM-4 was a significantly more effective contraceptive th
an a commercially available N-9 gel [100% vs. 68.7% protection; P < 0.05, F
isher's exact teal]. Unlike the rabbits treated with N-9, none of the rabbi
ts that were given GM-4 intravaginally for 10 consecutive days developed ep
ithelial ulceration, edema, leukocyte influx, or vascular congestion charac
teristic of inflammation. Furthermore, repeated intravaginal application of
GM-4 for up to 13 weeks in mice had no adverse effects on survival, growth
, metabolism, or organ function.
Conclusion: We conclude that the novel spermicidal GM-4 formulation is safe
and significantly more effective than N-9 in preventing conception. (C) 20
01 by American Society for Reproductive Medicine.