Net delay of next conception by contraception: A highly simplified case

Area of Science:

• Reproductive Health
• Biostatistics
• Demography

Background:

• Understanding factors influencing time to next conception is crucial for reproductive health and family planning.
• Previous models have limitations in comprehensively assessing contraceptive impacts on conception timing.

Purpose of the Study:

• To present and apply a probability model for tracking women from pregnancy outcome to next conception.
• To quantify the impact of contraceptive use and characteristics on the duration to next conception.

Main Methods:

• Developed a probability model based on Perrin and Sheps' work, assuming female homogeneity and constant fecundity.
• Modeled scenarios with no contraception, single contraceptive use, and sequential use of two contraceptive methods.
• Calculated expected durations to next conception based on pregnancy outcomes, anovulation, fecundability, and contraceptive details.

Main Results:

• The model allows calculation of expected conception durations considering various factors like previous pregnancy outcome and contraceptive effectiveness.
• It enables comparative analysis by pairing model runs to isolate the effect of specific contraceptive methods.
• The net delay in conception attributable to a contraceptive method can be computed by differencing mean durations.

Conclusions:

• The developed probability model provides a robust framework for analyzing conception timing in relation to reproductive events and contraceptive use.
• This tool can accurately assess the impact of different contraceptive strategies on fertility.
• The model offers valuable insights for reproductive health policy and family planning interventions.