Intervals after stillbirth, neonatal death and spontaneous abortion and the risk of adverse outcomes in the next pregnancy in rural Bangladesh
Bareng A. S. Nonyane (1), Maureen Norton (2), Nazma Begum (1), Rasheduzzaman M. Shah (1), Dipak K. Mitra (3) , Gary L. Darmstadt (4), Abdullah H. Baqui (1) for the Projahnmo Study Group in Bangladesh
(1) International Center for Maternal and Newborn Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; (2) Bureau for Global Health, Office of Population and Reproductive Health, USAID, Washington, D.C., USA; (3) School of Public Health, Independent University, Bangladesh (IUB), Dhaka, Bangladesh; (4) March of Dimes Prematurity Research Center, Division of Neonatology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA;
Studies have revealed associations between preceding short and long birth-to-birth and birth-to-pregnancy intervals and poor pregnancy outcomes. Most studies have examined intervals that began with a live birth. Using data from Sylhet Bangladesh, we examined the effect of inter-outcome intervals (IOI) starting with a non-live pregnancy outcome on subsequent pregnancy outcomes.
We used pregnancy histories of 33,495 married women aged 15-49 years, with 64,897 pregnancy outcomes between 2000 and 2006. We examined the effects of the preceding outcome and the IOI length on the risk of stillbirth, neonatal death, and spontaneous abortion using multinomial logistic regression models.
IOIs of 27-50 months and live births were baseline comparators. Stillbirths followed by IOIs <=14 months (< five month inter-pregnancy interval [IPI]) had increased risk for spontaneous abortion with adjusted relative risk ratio (aRRR) and 95% confidence interval of 2.53 (1.19, 5.36). Stillbirths followed by IOIs 7-14 months had aRRR 2.00 (1.39, 2.88) for stillbirths. Neonatal deaths followed by IOIs<=6 months had aRRR 28.2 (8.59, 92.63) for spontaneous abortion. Neonatal deaths followed by 7-14 and 15-26 months (< 17 month inter-pregnancy interval) had aRRRs 3.08 (1.82, 5.22) and 2.32 (1.38, 3.91), respectively, for stillbirths; and 2.81 (2.06, 3.84) and 1.70 (1.24, 3.84), respectively, for neonatal deaths. Spontaneous abortions and IOIs <=6 months and 7-14 months had, respectively, aRRRs 23.21 (10.34, 52.13) and 1.80 (0.98, 3.33) for spontaneous abortion.
In rural northeast Bangladesh, short intervals after stillbirth, neonatal death, and spontaneous abortion were associated with a high risk of a similar outcome in the next pregnancy. Two studies from similar settings have found benefits of waiting six months after adverse pregnancy outcomes before conceiving again, suggesting that incorporating this advice into programs should be considered.
The Projahnmo trial was registered with ClinicalTrials.gov NCT00198705.
The study was approved by the Johns Hopkins Bloomberg School of Public Health committee on human research and the Ethical Review Committee of the International Centre for Diarrheal Disease Research, Bangladesh (ICDDR,B). Verbal informed consent was obtained from all participating women.
Keywords: Pregnancy spacing, stillbirth, neonatal death, spontaneous abortion