The optimum length of time between pregnancies appears to be 
18 to 23 months .

Women who conceive less than 18 months or greater than 23 months after a previous delivery (vaginal or cesarean) seem to be at increased risk for delivering a preterm or a low birth weight infant. Conceiving less than 6 months or greater than 50 months after a previous delivery appears to increase the risk for both fetal and early neonatal death.

REFERENCES
Zhu B-P, Rolfs RT, Nangle BE, Horan JM. Effect of the interval between pregnancies on perinatal outcomes. N Engl J Med 1999;340:589–94 PMID:10029642

Conde-Agudelo A,Birth spacing and risk of adverse perinatal outcomes: a meta-analysis. JAMA. 2006 Apr 19;295(15):1809-23. PMID:16622143
 

Created: 11/26/2007
Reviewed: Mark  Curran, M.D.