Van der Wijden C, Kleijnen J, Van den Berk T. Lactational amenorrhea method for family planning. Cochrane Database Syst Rev. 2015;(4):CD001329.
Key Results
For the primary outcome, pregnancy, two controlled studies of LAM users reported life table pregnancy rates at six months of 0.45% and 2.45%, one controlled study reported 5% pregnancies in the absence of life table rates per month, and eight uncontrolled studies of LAM users reported pregnancy rates of 0% to 7.5%. Life table pregnancy rates for fully breastfeeding women who were amenorrheic but not using any contraceptive method were 0.88% in one study and 0.9% to 1.2% (95% confidence interval 0.0 to 2.4) in a second study, depending on the definition of menstruation used. The life table menstruation rate at six months in all studies varied between 11.1% and 39.4%.
Conclusion
We found no clear differences in life table pregnancy rates between women using LAM and being supported in doing so, and fully breastfeeding amenorrheic women not using any method. As the length of lactation amenorrhoea in women using LAM differed greatly between the populations studied, and was population specific, it is uncertain whether LAM extends lactational amenorrhoea.