Pakistan, the world's seventh most populous country of about 138 million people, is beset with severe problems in its maternal and child health sector. The official maternal mortality ratio for Pakistan is reported as 340 per 100,000 live births. The overall goal to conduct a prospective observational study to identify the risk factors for adverse pregnancy outcomes including reproductive tract infections such as BV, and other physical, dental, nutritional, psychosocial, and behavioral characteristics. The primary objective is to examine the association between BV in pregnant women at 20-26 weeks gestation and various other biochemical infection markers with adverse pregnancy outcomes (i.e., perinatal mortality [PNM], neonatal mortality, low birth weight [LBW], spontaneous preterm delivery [SPTD], premature rupture of membranes [PROM], histological chorioamnionitis).

Additionally, this study will explore the relationship of various health behaviors and health status to the presence of perinatal infections. A total of 1,500 pregnant women will be enrolled in the study. A matched case-control study will be conducted at the end of the data collection period to evaluate the use of markers for the prediction of infection related perinatal mortality and infection related SPTD. All investigators and laboratory personnel will remain blinded to the identity of specimens through the use of unique study identifier numbers. Collected data will then be unblinded, analysed, and correlated with the previously collected demographic, obstetrics, and neonatal outcome, microbiology and histopathological data.

Based on the findings of this study, appropriate interventions to address reproductive tract infection (RTI) could be developed and field-tested in Pakistan. We expect that these interventions, once successfully field-tested, could be widely used to improve maternal and child survival in Pakistan and other developing countries. Given the critical state of maternal and child health in Pakistan, and considering the emerging evidence that infections could lead to poor pregnancy outcomes, this study is extremely relevant and timely, and it has the potential to contribute significantly toward the improvement of reproductive health in Pakistan.

Primary outcome is perinatal mortality. Secondary outcomes include birth weight; spontaneous delivery occurring before 37 weeks gestation; rupture of fetal membranes before 37 weeks of gestation; and maternal death. The sample size was based on 25% prevalence of BV in the control group; 10 percent dropout rate; 80 percent power; and a two-tailed type I error of 0.05.