Association Between Short Birth Interval and Immediate Adverse Perinatal Outcomes Among Women Delivering at a Tertiary Hospital in South-Western Uganda.

Purpose: Immediate adverse perinatal outcomes (IAPO) are more likely to occur in women with short inter-birth birth intervals (SIBI) compared to optimal inter-birth interval (OIBI). This study determined the association between short inter-birth interval and immediate adverse perinatal outcomes among women delivering at Mbarara Regional Referral Hospital (MRRH).

Patients and methods: We conducted a cross-sectional study among mother-baby pairs admitted to MRRH postnatal ward within 24 hours after delivery from the period running from March 2023 to June 2023. The primary exposure variable was birth interval and the primary outcome was IAPO. Data was collected using a structured questionnaire. Modified Poisson Regression analysis was used to determine the relationship between birth interval and immediate adverse perinatal outcomes.

Results: Of the 688 participants enrolled, the mean age was 28.06 ±5.04 years. Majority were married (97.8%) and referred to in (44.6%). Low birth weight was significantly higher among women with SIBI compared to OIBI ((9.9% versus 5.8%, p=0.047), while other adverse outcomes (preterm birth, stillbirth, and NICU admissions) were more frequent but not statistically significant. A SIBI was significantly associated with IAPO (aPR): 1.46; 95% C. I [1.02, 2.09], p=0.038). Other factors independently associated with adverse perinatal outcomes were maternal age<20 years ([aPR]: 2.66; 95% C.I [1.05,6.73], p=0.039), obstetric complications (aPR: 2.16; 95% C.I [1.34, 3.48], p=0.002), having a diagnosis of fetal distress (aPR: 2.61; 95% C.I [1.80, 3.79], p<0.001), and a history of malaria in pregnancy (aPR: 1.66; 95% C.I [1.12, 2.48], p=0.013).

Conclusion: A SIBI significantly increases the risk of IAPO. Additionally, maternal age below 20 years, the presence of obstetric complications, a diagnosis of fetal distress, and a history of malaria in pregnancy independently contribute to these unfavorable outcomes. We recommend health education and advocacy with emphasis for the utilization of family planning services so as to have OIBI.