The science behind the Billings Ovulation Method®(BOM) is “rock solid”. The World Organisation Ovulation Method Billings (WOOMB) International Limited has published a paper with such a name ‘Rock Solid Science: Studies of the Effectiveness of the Billings Ovulation Method®’ by Gillian Barker. In this excerpt of the lengthy but well-done article the stages of development of the BOM are detailed:
“Stage 1—Clinical studies and preliminary data: For couples wishing to avoid pregnancy – no pregnancies were observed when there was abstinence from intercourse on any days of discharge; no pregnancies were observed from any act of intercourse occurring 4+ days following the last day of the slippery sensation.
This last day of the slippery sensation was designated the Peak of fertility. For couples wishing to achieve pregnancy – many couples conceived when intercourse occurred on days of mucus discharge; there was one pregnancy from intercourse on the 3rd day past the Peak, a few pregnancies from intercourse on day 2 past the Peak and more from the day after Peak, but most pregnancies resulted from intercourse on the Peak day.