Stillbirth rates in low-middle income countries 2010 – 2013: a population-based, multi

In this cohort study conducted in low-resource settings across six countries in Asia,
sub-Saharan Africa and Latin America, the overall stillbirth rate was 28.9 per 1000
births. Since 2010, the stillbirth rates decreased in the Latin American and Indian
sites, with modest decreases in the Zambia or Kenya sites and increasing stillbirth
rates in the Pakistan site over the four-year period. The overall stillbirth rates
remained relatively high, ranging from 13.6 in Argentina to 56.5 per 1,000 births
in Pakistan. These rates are consistent with other modeling estimates 1].

This is one of the largest prospective studies of stillbirth in low-resource settings
in low to upper-middle income countries conducted to date. One of the study strengths
was that we obtained population-based outcomes with excellent coverage of the catchment
areas of the study communities, including very high enrollment and 98% follow-up to
obtain pregnancy outcomes. Furthermore, the study reflects four years of data. One
of the study’s limitations was that while we obtained signs of maceration, these were
through observation or report, which previous studies have suggested may over-represent
intrapartum stillbirth 16]. We were also unable to reliably capture the cause of stillbirth, given the high
proportion of births delivered outside of health care settings. However, the study
did collect basic demographic data and health care utilization by women, cared for
in a range of health care settings, with one-third delivered at home. As described
elsewhere, related research was conducted over the study period in which training
and supervision occurred to help ensure detection of stillbirth and differentiation
of macerated from non-macerated stillbirths 17-19].

The maternal socio-economic and maternal risk factors for stillbirth observed were
similar to those documented in low-middle income country studies conducted elsewhere
3-5,7-10]. That is, women who had less education and who were older were at significantly higher
risk for stillbirth. Similarly, those women having less access to antenatal care,
as documented through fewer ANC visits and reduced rates of prenatal testing, had
increased risk for stillbirth. While the rates of HIV and syphilis testing were associated
with the stillbirth rate, we assume the relationship is primarily explained by these
tests indicating the adequacy of antenatal and obstetric care. Similarly, provision
of tetanus immunization, which has not been associated with stillbirth, is also a
marker for the adequacy of care.

Being preterm and of low birth weight were both associated with more than ten-fold
risks of being a stillbirth compared to a live birth. In this case, it was not possible
to distinguish whether the preterm labor increased risk for stillbirth or whether
the condition that caused the stillbirth may have also precipitated the early delivery.
Regardless, prematurity and low birth weight were strongly associated with stillbirth.

Women with complicated pregnancies, including those with multiple gestations and breech
presentations, were at significantly increased risk for stillbirth in our study. Similarly,
those with major congenital anomalies had increased of stillbirth, similar to risks
shown from other LMIC 4]. Across the Global Network sites, non-macerated stillbirths represented about 67%
of all stillbirths. While this rate is higher than some other LMIC studies, it is
consistent with studies suggesting that intrapartum stillbirth rates are highest in
the geographic regions with high stillbirth rates 13]. This is an important relationship, as an intrapartum stillbirth suggests that the
fetus was alive at time of delivery care, that the stillbirth likely occurred in association
with intrapartum asphyxia or trauma, and that the stillbirth may have been preventable
12,20]. With the high proportion of intrapartum stillbirths, our results suggest that stillbirth
rates could be substantially reduced by focusing on these deaths with improved obstetric
labor and delivery care. While many could be prevented with improved care, a proportion
of non-macerated stillbirths are associated with other causes such as major congenital
anomalies 21]. Our results also showed overall higher stillbirth rates at hospitals and with physicians,
relative to the stillbirth rates found at lower levels of care. Because this study
was conducted at the population level, this finding is likely to be associated with
the higher risk deliveries presenting at these higher levels of care 21]; however, it may also have implications for the quality of care available at some
of those facilities 12,22].

Prior research has suggested that timely access to high-quality care at delivery can
substantially reduce stillbirth, especially those occurring in the intrapartum period,
including those associated with many types of complicated pregnancies 20,23,24]. We explored this issue through examining cesarean section and stillbirth further
and found that altogether 8% of all women with a stillbirth were delivered by cesarean
section. Because cesarean section is generally not indicated where there is a fetal
death 25-27], we examined the indications and noted that the majority of these cesarean sections
were conducted for obstructed labor, major antepartum hemorrhage, or malposition.
While these conditions are considered appropriate cesarean section indications 25], in these settings the cesarean section was inadequate or performed too late to save
the fetus. The fact that such a high proportion of women with stillbirths had cesarean
section suggests that the primary motivation may have been to save the mother’s life.
However, further research would be needed to confirm this speculation. Additionally,
while research in HIC has suggested that stillbirths associated with these types of
complications are generally preventable with quality obstetric care, this finding
would also need to be further explored in low-resource areas.

Tools such as perinatal audits have been shown to improve quality of facility care
and reduce stillbirth 28]. Quality of care includes the judgment to determine which women are at risk and require
interventions such as cesarean section, and performing these interventions well. However,
in addition to the quality of obstetric care, the timeliness of providing obstetric
care is critical, especially to save the fetus. As suggested by our results, cesarean
section performed late may not benefit the fetus or poorly performed instrumental
delivery may increase risk. Furthermore, the increased mortality associated with hospital
and physician deliveries suggested that women with risk may have been seeking care;
however, the care may have been delivered too late to save the fetus.