Ramos R, Kennedy K I, Visness C M
Comprehensive Family Planning Center, Jose Fabella Memorial Hospital, Manila, Philippines.
BMJ. 1996 Oct 12;313(7062):909-12. doi: 10.1136/bmj.313.7062.909.
To determine the contraceptive efficacy of the lactational amenorrhoea method.
Non-comparative prospective trial.
Urban Manila, the Philippines.
485 lower income, educated women with extensive experience of breast feeding.
Women were offered all available contraceptives for use after birth. Those who chose the lactational amenorrhoea method were taught the method, screened for the study, and followed for 12 months to determine the risk of pregnancy when the method was used.
Life table pregnancy rates during correct and incorrect use of the method, censored monthly in the event of sexual abstinence or the use of another contraceptive method.
The lactational amenorrhoea method was 99% effective when used correctly (that is, during lactational amenorrhoea and full or nearly full breast feeding for up to six months). At 12 months the effectiveness during amenorrhoea dropped to 97%.
The lactational amenorrhoea method provided as much protection from pregnancy as non-breast feeding women experience with non-medicated intrauterine devices and barrier methods. The contraceptive effect of lactation cannot be attributed to lactational or postpartum abstinence.
确定哺乳期闭经法的避孕效果。
非对比性前瞻性试验。
菲律宾马尼拉市。
485名低收入、受过教育且有丰富母乳喂养经验的女性。
为产后女性提供所有可用的避孕方法供其选择。选择哺乳期闭经法的女性接受该方法的培训，进行研究筛查，并随访12个月，以确定使用该方法时的怀孕风险。
正确和错误使用该方法期间的生命表妊娠率，若出现禁欲或使用其他避孕方法，则每月进行删失处理。
正确使用哺乳期闭经法（即在哺乳期闭经且完全或几乎完全母乳喂养长达6个月期间）时，其避孕有效率为99%。到12个月时，闭经期间的有效率降至97%。
哺乳期闭经法提供的避孕效果与非母乳喂养女性使用无药宫内节育器和屏障法的避孕效果相当。哺乳期的避孕效果不能归因于哺乳期或产后禁欲。
