Pregnancy outcome and the time required for next conception

Area of Science:

• Reproductive Health
• Demography
• Sociology

Background:

• Understanding pregnancy intervals is crucial for reproductive health research.
• Previous studies have not fully accounted for biases in retrospective data collection.

Purpose of the Study:

• To analyze pregnancy intervals in Taiwanese women.
• To investigate the influence of preceding pregnancy outcomes and maternal age on conception time.
• To estimate the impact of truncation and memory biases on interval data.

Main Methods:

• Analysis of pregnancy intervals from a 1962 survey of 2,443 married Taiwanese women (aged 20-39).
• Estimation of pregnancy interval moments (average and variance) using statistical methods.
• Indirect estimation of post-partum amenorrhoea using pregnancy interval data.
• Accounting for truncation and memory biases through age-based cross-classification.

Main Results:

• Pregnancy intervals were longer after live births compared to fetal deaths, assuming no contraception.
• Conception time increased with maternal age, regardless of pregnancy outcome.
• Truncation and memory biases were found to be compensatory in this sample.

Conclusions:

• Maternal age and preceding pregnancy outcome significantly affect the time to next conception.
• Statistical biases in retrospective data can be managed to provide reliable reproductive health insights.
• Findings contribute to understanding fertility patterns in a specific demographic context.