Effect of the ethinylestradiol/norelgestromin contraceptive patch on body composition. Results of bioelectrical impedance analysis in a population of Italian women.
BACKGROUND
As weight gain is one of the most frequently cited reasons for not using and for discontinuing hormonal contraceptives, in an open-label, single-arm, multicentre clinical study we evaluated the effect of the ethinylestradiol/norelgestromin contraceptive patch (EVRA, Janssen-Cilag International, Belgium) on body composition using bioelectrical impedance analysis (BIA).


METHODS
Body weight and impedance vector components (resistance (R) and reactance (Xc), at 50 kHz frequency, Akern-RJL Systems analyzer) were recorded before entry, after 1, 3 and 6 months in 182 Italian healthy women aged 29 yr (18 to 45), and with BMI 21.8 kg/m2 (16 to 31). Total body water (TBW) was estimated with a BIA regression equation. Vector BIA was performed with the RXc mean graph method and the Hotelling's T2 test for paired and unpaired data.


RESULTS
After 6 months body weight increased by 0.64 kg (1.1%) and TBW increased by 0.51 L (1.7%). The pattern of impedance vector displacement indicated a small increase in soft tissue hydration (interstitial gel fluid). Body composition changes did not significantly differ among groups of previous contraceptive methods. Arterial blood pressure did not significantly change over time.


CONCLUSIONS
After 6 months of treatment with the ethinylestradiol/norelgestromin contraceptive patch we found a minimal, clinically not relevant, increase in body weight less than 1 kg that could be attributed to an adaptive interstitial gel hydration. This fluctuation is physiological as confirmed by the lack of any effect on blood pressure. This could be useful in increasing women's choice, acceptability and compliance of the ethinylestradiol/norelgestromin contraceptive patch.
Piccoli
Antonio
A
Department of Medical and Surgical Sciences, University of Padova, Italy. apiccoli@unipd.it
Crosignani
PierGiorgio
P
Nappi
Carmine
C
Ronsini
Salvatore
S
Bruni
Vincenzina
V
Marelli
Silvia
S
D000279:Administration, Cutaneous; D000293:Adolescent; D000328:Adult; D001823:Body Composition / Q000187:drug effects*; D015992:Body Mass Index; D001834:Body Water / Q000187:drug effects / Q000378:metabolism; D003277:Contraceptives, Oral, Combined / Q000008:administration & dosage* / Q000009:adverse effects*; D004338:Drug Combinations; D017097:Electric Impedance; D004997:Ethinyl Estradiol / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006801:Humans; D008875:Middle Aged; D009644:Norgestrel / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives; D010091:Oximes / Q000008:administration & dosage / Q000009:adverse effects; D015430:Weight Gain / Q000187:drug effects* / Q000502:physiology; D055815:Young Adult
D003277:Contraceptives, Oral, Combined; D004338:Drug Combinations; D010091:Oximes; D009644:Norgestrel; D004997:Ethinyl Estradiol; C449219:norelgestromin