Time to conception after miscarriage: How long to wait?

An interpregnancy interval (IPI) of < 6 months following miscarriage is associated with an increased live birth rate in subsequent pregnancy, lower risks of preterm birth and subsequent miscarriage, and no difference in rates of stillbirth, pre-eclampsia, and low birth weight infants (strength of recommendation [SOR]: A, well-done meta-analysis). (IPI is defined as the time between the end of one pregnancy and the last menstrual period of a subsequent one.)

A very short IPI (< 3 months), when compared with an IPI of 6 to 18 months, is associated with the lowest rate of subsequent miscarriage (SOR: B, cohort study). However, for women who experience a pregnancy loss at 14 to 19 weeks’ gestation, an IPI < 3 months is associated with an increased risk of miscarriage or birth before 24 weeks’ gestation.

 

IPI shorter than 6 months carries fewer risks.

IPI shorter than 3 months following First trimester has lowest risk of all.  

But a short IPI after second-trimester loss increases risk of miscarriage

Short IPI may be linked to anxiety in first trimester of next pregnancy

RECOMMENDATIONS

The American College of Obstetricians and Gynecologists’ Practice Bulletin on Early Pregnancy Loss states that no quality data exist to support delaying conception after early pregnancy loss (defined as loss of an intrauterine pregnancy in the first trimester) to prevent subsequent pregnancy loss or other pregnancy complications.

WHO recommends a minimum IPI of at least 6 months after a spontaneous or elective abortion. This recommendation is based on a single multi-center cohort study in Latin America that included women with both spontaneous and induced abortions.

Source:  J Fam Pract. 2019 October;68(8):E12-E14