Keywords mortality - maternal - COVID-19 - postpartum period - health impact assessment
Palavras-chave mortalidade materna - COVID-19 - período pós-parto - avaliação do impacto na saúde
Introduction
Maternal mortality is a profound violation of the human rights of women, mainly because
it is considered preventable in 92% of the cases.[1 ] Thus, reducing maternal mortality is one of the goals of the World Health Organization
(WHO) sustainable development goals for 2030.[2 ]
In 2020, the Sars-CoV-2 pandemic showed up as a new obstacle to ensuring maternal
and fetal health: pregnant and postpartum women were considered an infection risk
group for developing more serious complications.[3 ]
In the same year, a Brazilian study found a12.7% lethality rate due to infection in
the obstetric population, higher than in other countries.[4 ]
[5 ]
[6 ]
[7 ] In June 2020, 5 months after the 1st case of COVID-19 in the country, the number of mothers who lost their lives due to
the disease already represented 10% of the total annual maternal deaths.[4 ] Throughout the year, 453 deaths were registered, with a weekly average of 10.5 deaths.[8 ]
In addition, 4,245 pregnant and postpartum women were infected by COVID-19 in 2020,
and 352 of them (7.7%) died. When considering only the gestational period, 3,459 infections
and 221 deaths were registered, recording 6.3% of deaths. However, when only puerperal
women were considered, 786 infections and 131 deaths were registered, reaching a higher
rate (14.3% of the patients died), which suggests that the puerperal period is more
lethal than the gestational period.[8 ]
It is important to emphasize that a large proportion of pregnant and postpartum women
who died from COVID-19 infection did not have comorbidities or risk factors; in other
words, they did not fit the definition of high-risk pregnancies,[9 ] when the life or health of the pregnant woman or of the fetus are more likely to
be affected than those of the considered population.[10 ]
Considering the effects of COVID-19 in the Brazilian obstetric population, the present
study aims to assess the possible impact of the pandemic on maternal mortality among
admissions for childbirth in 2020 in relation to the history of the last 10 years,
according to the gestational risk and route of delivery in Brazil.
Methods
This is a quantitative ecological study. The study population consisted of pregnant
women who underwent hospital births at the Brazilian Unified Health System (SUS, in
the Portuguese acronym), registered in the Hospital Information System (SIH/SUS, in
the Portuguese acronym), in the period from 2010 to 2020. Complete data were obtained
from health information available in the database of the Information Technology Department
of the Brazilian Public Healthcare System (DATASUS, in the Portuguese acronym). Data
were exported to Microsoft Excel (Microsoft Corporation, Redmond, WA, USA) and were
analyzed using the software Stata version 12.0 (StataCorp, College Station, TX, USA).
The population of interest for the study was pregnant women who underwent hospital
births at the SUS. The mortality among admissions for childbirth was obtained based
on the number of admissions for childbirth who had maternal death as the outcome divided
by the total number of admissions, for each route of delivery, gestational risk, and
year of analysis. We used a 104 constant. The average mortality for the period between 2010 and 2019 was compared
with the maternal mortality rate of 2020. The gestational risk and route of delivery
were classified, as recorded at the SIH, in: high-risk vaginal delivery; low-risk
vaginal delivery; high-risk cesarean delivery; and low-risk cesarean delivery. This
categorization is recorded in the system by the health professional responsible for
the assistance, considering the definition of high or low gestational risk.[10 ]
To analyze a possible effect of COVID-19 on maternal mortality, the period from 2010
to 2019 was considered the baseline, and the year 2020, because of the introduction
of COVID-19, the exposure period. So, to measure the impact of 2020 and, indirectly,
of the pandemic on mortality among admissions for childbirth, the average mortality
in the period between 2010 and 2019 (considered nonexposed period rates) was compared
with the mortality presented in 2020 (1st year of the pandemic, considered the exposed period). The rate ratio (RR) was interpreted
as the risk of death in 2020 in relation to the average of the previous period. Confidence
intervals (CIs) of 95% were estimated, with a significance level of 5%. The analyses
were carried out using the Stata statistical program package version 12.0 (StataCorp,
College Station, TX, USA) and OpenEpi.
All data is public and available on the Internet with unrestricted access data and
without identifying individuals. The present publication is part of a project approved
by the Ethical Review Board (No. 4.482.150 of December 2020).
Results
The total number of pregnant women hospitalized for childbirth between 2010 and 2020
was 20,995,023, and 5,761 deaths after birth were recorded ([Figure 1 ]). In 2020, the 1st year of the COVID-19 pandemic, 1,821,775 pregnant women were hospitalized for childbirth
and 651 deaths were reported, which represents 8.7% of the total hospitalizations
and 11.3% of the maternal deaths in the period analyzed.
Fig. 1. Absolute number of admissions for childbirth and maternal deaths during hospitalization
according to gestational risk and mode of delivery between 2010 and 2020. *Admissions
for childbirth at any gestational age were included.
Besides, maternal mortality in high-risk pregnant women was higher than in low-risk
pregnant women, in every route of delivery in the period. The average rate of maternal
mortality of low-risk pregnant women from 2010 to 2019 was 2.11 (95%CI: 1.90–2.34)
deaths per 10,000 admissions for childbirth, and the average rate of maternal mortality
among high-risk pregnant women was 7.37 (95%CI: 6.24–8.66) deaths per 10,000 admissions
for childbirth ([Table 1 ]).
Table 1.
Childbirth-related mortality rates in Brazil, according to gestational risk, and rate
ratio for 2020 compared with the average for 2010-2019
Average 2010–2019
2020
Hospitalization
n
Deaths
n
MR (95%CI)
Hospitalization
n
Deaths
n
MR (95%CI)
RR
(95% CI)
1915817
511
2.67
(2.44–2.91)
1821775
651
3.57
(3.31–3.86)
1.34
(1.19–1.50)
Gestational risk/Chilbirth
Low risk
1,713,766
362
2.11
(1.90–2.34)
1554767
458
2.95
(2.68–3.22)
1.40
(1.21–1.60)
Caesarean
651,916
210
3.22
(3.09–3.36)
673633
256
3.80
(3.35–4.30)
1.18
(1.04–1.34)
Vaginal
1,061,850
152
1.43
(1.36–1.50)
881134
202
2.29
(1.99–2.63)
1.60
(1.39–1.85)
High risk
202,051
149
7.37
(6.24–8.66)
267008
193
7.23
(6.24–8.32)
0.98
(0.79–1.21)
Caesarean
122,792
111
9.04
(8.51–9.58)
168408
146
8.67
(7.32–10.2)
0.96
(0.81–1.14)
Vaginal
79,259
38
4.77
(4.30–5.26)
98600
47
4.76
(3.50–6.34)
0.99
(0.74–1.35)
Abbreviations: MR, Mortality among admissions for childbirth: number of deaths/number
of admissions for childbirth x 10,000; RR, relative risk considering 2020 as exposed
year and the average of the period between 2010 and 2019 as baseline.
In 2020, there was an increase in maternal mortality compared with the average of
the previous 10 years, with an increment of 40% in low-risk pregnancies. Women with
low-risk pregnancies who underwent vaginal delivery had a 60% (RR = 1.6; 95%CI: 1.39–1.85)
higher risk of dying in 2020, while those who underwent cesarean deliveries had an
18% higher risk of death (RR = 1.18; 95%CI: 1.04 -1.34) in 2020 when compared with
the average between 2010 and 2019 ([Figure 2 ]).
Fig. 2. Mortality among admissions for childbirth performed in Brazil, according to route
of delivery and pregnancy risk, 2010-2019 and 2020. *Statistically significant comparison
Regarding high-risk pregnancies, no significant differences were observed in mortality
after vaginal or caesarean delivery in high-risk pregnancies women in the studied
period.
Discussion
The present study explored the maternal mortality among admissions for childbirth
in the period between 2010 and 2020, focusing on the differences of 2020 compared
with a 10-year baseline period. Higher mortality rates in high-risk pregnant women
compared with low-risk is a known fact, and the association with cesarean delivery
can occur because the conditions of high-risk pregnancy can be configured as indications
for surgical delivery.[11 ]
[12 ]
[13 ] Considering this prior knowledge, the increased deaths of low-risk pregnant women,
regardless of the route of delivery performed, is remarkable when comparing the period
between 2010 and 2019 with the year 2020.
The increase in maternal mortality only in low-risk pregnancies allows us to suggest
that the COVID-19 pandemic has been categorized as a threat to the life of this group
not known until then, considering that this is a challenging situation for general
health, and especially in this group with a higher immune vulnerability.
While maternal mortality in high-risk pregnancies has permanently high rates, mainly
due to hemorrhage, sepsis, and hypertensive disorders, low-risk pregnant women have
considerably lower mortality rates.[11 ]
[14 ] Thus, the COVID-19 pandemic stood out as a more dramatic and relevant harm to mothers
who did not have a previous risk factor of an adverse outcome.
It is important to emphasize that, during the pandemic, prenatal care was highly affected
by the fear of pregnant women to seek assistance and by barriers imposed by health
care facilities for women.[15 ]
[16 ] The focus on the care of COVID-19-symptomatic individuals in primary care services
resulted in the late arrival at hospitals of pregnant women with more serious conditions,
which could have been avoided with timely and quality prenatal care.[17 ] In this context, high-risk pregnant women have become a priority in prenatal consultations,
since many health services have changed the management of care for pregnant women,
reorganizing the flow and using risk classification screening in order to focus on
care for COVID-19 patients.[18 ] Therefore, the restriction of prenatal care, especially for low-risk pregnant women,
as an indirect consequence of the COVID-19 pandemic, leads to losses in the treatment
of maternal nutritional deficits, in screening for infections, and even in the classification
as high-risk pregnancy if necessary, and may lead to worse maternal outcomes in this
group.[19 ]
In addition, high-risk pregnant women, aware of their most vulnerable health condition,
receive greater medical guidance and, associated with the fear of infection with their
risk condition, may have followed social isolation and hygiene measures more intensively
and, therefore, being less frequently a target of infection and death by COVID-19.[20 ]
However, it is a fact that, in Brazil, puerperal death by COVID-19 is mainly related
to chronic problems in women's health, such as lack of resources, obstetric violence,
insufficient beds, and poor-quality prenatal care.[16 ] Thus, the Brazilian health system was not prepared for all pregnant women to become
“high-risk pregnant women” because of COVID-19, requiring greater attention and assistance
while the health system was already overloaded. A study carried out with 978 Brazilian
pregnant and postpartum women agrees with the present study in concluding that 51.6%
of the women who died due to COVID-19 infection did not have comorbidities or risk
factors. Besides, the study showed that being black, living in a periurban area, not
having access to Family Health Strategy or living > 100km away from the notification
hospital were associated with an increased risk of a worse outcome.[9 ]
Therefore, the precarity of care for pregnant women and the structural racism in pandemic
times may have had more impact on the deaths of postpartum women in Brazil than the
association between COVID-19 infection and their previous comorbidities. A Brazilian
study reinforces the insufficiency of the health system in women's healthcare by showing
that 20% of pregnant and postpartum women hospitalized with COVID-19 did not have
access to the intensive care unit and (ICU), and a third of them did not have access
to mechanical ventilation.[4 ] An article published in July 2020 in The Lancet has already predicted higher maternal
mortality in low- and middle-income countries due to the indirect effect of COVID-19,
resulting in lower access to healthcare and to food due to the reorganization around
COVID-19. The study found that 60% of additional maternal deaths would be related
to basic management of women's healthcare as clean birth environments, parenteral
administration of uterotonics, antibiotics, and anticonvulsants.[21 ] Thus, healthy pregnant and postpartum women who would need minimal assistance ended
up being victims of the disorganization of the health system in pandemic times and
lost their lives.
Since vaccination was recommended primarily for high-risk pregnant women, this scenario
can still be maintained in 2021.[22 ] Thus, the mortality rates already predicted for high-risk pregnant women would remain
the same, regardless of infection by COVID -19, and would increase mortality in low-risk
pregnancies, since they were not yet immunized, and the possible infection would add
risk to the pregnancy of these women. Therefore, the present analysis is considered
preliminary and further studies with a detailed analysis of 2021 are needed to compose
a more complete analysis of the pandemic period.
Finally, the increase in maternal mortality among admissions for childbirth occurred
both after cesarean delivery and after vaginal delivery. However, it is noteworthy
that there was a greater increase after vaginal delivery (60%) compared with cesarean
delivery (18%). The literature is conflicting in assessing if the mode of delivery
interferes in the maternal mortality during COVID-19 infections. A systematic review
of 11,758 pregnant women found that the majority of COVID-19-infected women who died
had a cesarean section (58.3%), while 25% had vaginal delivery and 16,7% of the patients
were not full-term.[23 ] However, other systematic reviews have not found significant outcome effects comparing
modes of delivery.[24 ]
[25 ]
As for the limitations of the present study, since it is an ecological and exploratory
study, comparing 1 year to a period of 10 years, a cause-effect relationship cannot
be defined. Also, because of the availability of the data, we considered in comparisons
only 1 year (2020) as the risk from the pandemic and did not evaluate the complete
trend over the years. In addition, there are limitations inherent to the use of secondary
data, depending on the quality of the record carried out and on the impossibility
of evaluating the cause of death, as well as the sociodemographic profile of pregnant
women, since these data are not available for analysis. Besides, there are few studies
on the mortality after birth in hospitalized women, which made the comparison with
the literature difficult. However, based on the increased maternal mortality of low-risk
pregnancy in Brazil in 2020 compared with the period between 2010 and 2019, it is
suggested that this is another unfavorable outcome of the COVID-19 pandemic in the
country, since this group was characterized as a risk group for infection.
Conclusion
Maternal mortality among admissions for childbirth according to SUS data increased
in 2020 in low-risk pregnancies compared with the average number of deaths between
2010 and 2019. The increase was of 18% after cesarean section and of 60% after vaginal
delivery. Regarding high-risk pregnancies, no significant differences were observed.
The increase in maternal mortality only in low-risk pregnancies suggests that the
COVID-19 pandemic stood out as a more dramatic and relevant harm to mothers who did
not have a previous risk factor of an adverse outcome. Since puerperal death due to
COVID-19 in Brazil is mainly related to chronic problems in women's health, the precarity
of care for pregnant women in pandemic times may have had a greater impact on deaths
among admissions for childbirth in Brazil than the association between COVID-19 infection
and their previous comorbidities.
