Recurrent short interpregnancy interval: Maternal and neonatal outcomes

Eur J Obstet Gynecol Reprod Biol. 2021 Sep:264:299-305. doi: 10.1016/j.ejogrb.2021.07.040. Epub 2021 Jul 27.

Abstract

Objective: To evaluate maternal and neonatal outcomes associated with recurrent short interpregnancy interval (IPI) in women in their third delivery.

Methods: A retrospective computerized database study of all women who delivered their first three consecutive deliveries in a single tertiary medical center over 20 years (1999-2019). Maternal and neonatal outcomes of women with recurrent short IPI (<6 months between the 1st and 2nd pregnancy and the 2nd and 3rd pregnancy) were compared to women with recurrent optimal IPI (18-48 months), and to women with a single short IPI (<6 months between the 1st and 2nd pregnancy followed by an optimal IPI of 18-48 months between the 2nd and 3rd pregnancy). Additionally, in the recurrent short IPI groups, outcomes of the 2nd and 3rd pregnancies were compared in order to achieve an ideal adjustment to background characteristics. Univariate analysis was followed by multiple logistic regression models; adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated.

Results: During the study period 10,569 women had three consecutive deliveries at our medical center, of those 338 (3.2%) women had recurrent short IPIs, and 1,021 (9.7%) had recurrent optimal IPIs. Recurrent short IPI was associated with a significantly higher risk of maternal anemia (Hb < 10gr%) on admission to labor (aOR 3.4 [95% CI 1.09-10.65], p = 0.04) and higher risk of small for gestational age neonates (aOR 10.4 [95% CI 2.32-46.93], p < 0.01), as compared with women with recurrent optimal IPI and significantly higher rates of low neonatal birth weights (2500 gr) and anemia (Hb < 10gr%) alongside lower rates of operative vaginal deliveries as compared with women with single short IPI followed by an optimal IPI. In the recurrent short IPI groups, the 3rd deliveries had significantly higher rates of in-labor cesarean and anemia (Hb < 10gr%) on admission as compared to their 2nd deliveries.

Conclusion: Recurrent short IPI is associated with maternal anemia and small for gestational age neonates. Guiding patients towards prolongation of the IPI should include explanatory comments on these outcomes.

Keywords: Anemia; Interpregnancy interval; Pregnancy outcome; Recurrent interpregnancy interval; Small for gestational age.

MeSH terms

  • Birth Intervals*
  • Delivery, Obstetric
  • Female
  • Humans
  • Infant, Low Birth Weight*
  • Infant, Newborn
  • Infant, Small for Gestational Age
  • Pregnancy
  • Retrospective Studies
  • Risk Factors