Clinical experience with NuvaRing® in Spain shows that the
monthly contraceptive ring is associated with a low incidence of hormone-related
adverse effects
I Lete
Lasa Santiago Apóstol Hospital, Gynecology Department,
Vitoria, Spain
Background The adverse effects most commonly reported during the
use of combined oral contraceptives (COCs) are nausea, headache and mastalgia.
Although a precise evaluation is complex, the incidence of these adverse effects
seems to be associated, at least partially, with the estrogen component of COCs.
Objective To evaluate the adverse effects associated with the use of
contraceptive hormones in users of the monthly contraceptive ring, NuvaRing®.
Methods A total of 896 Spanish women attending their normal centre-family
planning centre, hospital or private centre-to request contraceptive advice were
invited to participate in this observational, multicentre, prospective, open
study. Evaluations were carried out at baseline, and after three and six cycles
of ring use. NuvaRing® users were classified as either new users of hormonal
contraception (HC) or switchers-those switching from another HC method to the
monthly contraceptive ring. To evaluate the reduction in hormone-related adverse
effects, only the women who had switched from another HC method were assessed
for specific effects compared with baseline (their previous method).
Results Of
the total group of 805 women (mean age = 29 ± 6 years) who started using
NuvaRing®, 722 (90%) completed cycle 3 and 595 (74%) completed cycle 6. For
switchers (47.5% of the total group), the incidence of nausea, headache and
mastalgia was significantly lower after 3 cycles of ring use and this
improvement was maintained and strengthened after 6 cycles. More specifically,
the percentage of women who had breast hypersensitivity decreased from 6.4% at
baseline to 1.7% after 6 cycles of use (p<0.05). Headache also decreased, from 10% of women at baseline to 1.2% after 6 cycles (p<0.01). Although the percentage of women reporting nausea was already low at the start of the study (4.8%), this too fell significantly, to 0.4% after 6 cycles of ring use (p<0.05).
Conclusions The low incidence of hormone-related adverse effects
with the monthly contraceptive ring can be attributed to the ring’s low and
steady release of hormones.