Standard Days MethodAdvanced Slides

1

Efficacy Study of SDM

• Multi-site prospective study

• Services provided in existing programs

• Clients were followed monthly for 13 cycles

• Couples used the method correctly in 97% of cycles

• 478 women in the study, 43 got pregnant

• With correct use, the failure rate is 4.8

• With typical use the failure rate is 12.02

The Standard Days Method is based on

Viable sperm – up to 5 daysViable egg – up to 24 hours

The probability of pregnancy relative to ovulation.

3

Probability of Pregnancy from Intercourse on Days Relative to Ovulation

0%

5%

10%

15%

20%

25%

30%

35%

-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2

Pre

gn

an

cy

Ra

te

Ovu

lati

on

Source: Wilcox et al. 1998

4

The Standard Days Method is based on

Menstrual Cycle mid-point ± 3 days

Viable sperm – up to 5 daysViable egg – up to 24 hours

The probability of pregnancy relative to ovulation.

Timing of ovulation.

0%

5%

10%

15%

20%

25%

30%

35%

-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2

5

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

-4+ -3 -2 -1 0 1 2 3 4+

Probability of Ovulation Relative to Midpoint of Cycle

37%

16%14%12%

5%7%

1%

[Source: IRH Analysis of WHO 1981 data]6

The Standard Days Method is based on

0%

5%

10%

15%

20%

25%

30%

35%

-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2

Menstrual Cycle mid-point ± 3 days

Viable sperm – up to 5 daysViable egg – up to 24 hours

The probability of pregnancy relative to ovulation.

Timing of ovulation.

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

-4+ -3 -2 -1 0 1 2 3 4+

7

Day 8 Day 19

Determining the Fertile Window

8