Insertion of an intrauterine contraceptive device after induced or spontaneous abortion: a review of the evidence. Stanwood NL, Grimes DA, Schulz KF. Br J Obstet Gynaecol 2001; 108: 1168-1173

women discontinued due to problems with compliance to the study. Although women were not randomised, statistical tests showed both groups were similar with respect to demographic details of women and infants. The results indicated there was no significant difference in mean volume of milk produced between the two groups. Milk volume was measured as preand post-feed infant weight, over 24 hours as is the standard method of assessment. The composition of milk was similar in both groups in terms of triglyceride, protein and lactose content. It was calculated that the suckling infant received a maximum of 0.01–0.05 μg/kg/day desogestrel. This accounts for 2.6–3.7% of the daily maternal dose. No significant differences were noted in weight, length and biparietal diameter up to the seventh cycle of treatment. When infants were followed up at 18 and 30 months there were no clinically relevant differences between the two groups. The authors conclude that 75 μg desogestrel progestogen-only pill is a safe and effective method of contraception for lactating women. Efficacy cannot be concluded from the study as pregnancy rates were not reported, however the authors refer to the effectiveness of the desogestrel pill from published data where desogestrel is known to inhibit ovulation and has a 12-hour window for missed pills. Bias may have been introduced due to the nonrandomisation of women and also because neither patient nor researchers were blinded. It is unclear if laboratory staff were blinded. However, automated testing was used to identify milk composition. The safety of the desogestrel pill for lactating women has been demonstrated in this study.