Application of simple fertility awareness-based methods of family planning to breastfeeding women.
OBJECTIVE
To determine the potential efficacy of two simple fertility awareness-based methods of family planning-the Standard Days Method and the TwoDay Method-among breastfeeding women.


METHODS
Analysis of pre-existing data set, collected in 1986-1990.


METHODS
Pre-existing data from Australia, Britain, and Canada.


METHODS
Seventy-three breastfeeding women in Australia, Britain, and Canada, who were followed starting 42 days postpartum, until they had at least two potentially fertile cycles (defined as cycles with adequate levels of urinary estrogens (E) and pregnanediol glucuronide and a long enough luteal phase to support a pregnancy). We examine this existing data set.


METHODS
None.


METHODS
Probability of pregnancy from intercourse on different days of the cycle relative to ovulation for breastfeeding women following the instructions of the Standard Days Method or the TwoDay Method.


RESULTS
These two methods may be appropriate for different groups of breastfeeding women at different times. The Standard Days Method may be appropriate after cycle regularity is established, whereas the TwoDay Method may be a more effective option earlier in the postpartum period.


CONCLUSIONS
A need remains for a more appropriate simple fertility awareness-based method during this early period.
Arévalo
Marcos
M
Institute for Reproductive Health, Georgetown University, Washington, DC 20008, USA.
Jennings
Victoria
V
Sinai
Irit
I
D000328:Adult; D001364:Awareness; D001942:Breast Feeding / Q000523:psychology*; D005193:Family Planning Services / Q000379:methods*; D005260:Female; D005298:Fertility; D006801:Humans; D008597:Menstrual Cycle; D049590:Postpartum Period; D011247:Pregnancy; D011336:Probability; D013997:Time Factors