Women who become pregnant again less than 6 months after giving birth are more likely to deliver their next baby prematurely compared to those who wait 2 to 2.5 years.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
A systematic review of RCTs could determine whether intentionally shortening IPI to under 6 months causally increases preterm birth risk.
A systematic review of randomized trials in which women are assigned to conceive within 6 months versus 24–29 months after delivery, with preterm birth as the primary outcome, controlling for maternal age, prior preterm birth, and access to prenatal care.
An RCT could determine whether conceiving within 6 months after delivery directly increases preterm birth risk compared to longer intervals.
A multicenter RCT assigning 3,000 women with a prior live birth to either conceive within 6 months or delay conception for 24–29 months, with preterm birth before 37 weeks as the primary outcome, and adjustment for maternal BMI, smoking, and prior preterm birth history.
A prospective cohort could confirm whether short IPIs independently predict preterm birth after adjusting for maternal health, nutrition, and access to care.
A prospective cohort of 15,000 women from diverse socioeconomic backgrounds, tracking IPI from delivery to next conception and monitoring for preterm birth, with monthly assessments of nutrition, stress, and prenatal care utilization.
A case-control study could compare IPI distributions between women with preterm births and those with term births, isolating short IPI as a potential risk factor.
A matched case-control study of 2,500 preterm births and 5,000 term births, matched for maternal age, race, and prior preterm history, with IPI calculated from birth records and adjusted for smoking, education, and access to contraception.
A cross-sectional survey could estimate the proportion of preterm births occurring after short IPIs in a population.
A national cross-sectional survey of 100,000 women aged 18–40, asking about timing of last birth and current pregnancy outcome, with preterm birth confirmed by hospital records.