Efficacy and Tolerability of a Monophasic Combined Oral Contraceptive Containing Nomegestrol Acetate and 17β-Oestradiol in a 24/4 Regimen, in Comparison to an Oral Contraceptive Containing Ethinylestradiol and Drospirenone in a 21/7 Regimen

European Journal of Contraception and Reproductive Health Care - United Kingdom
doi 10.3109/13625187.2011.614029