Periodontitis During Pregnancy Clinical Trial
Official title:
"Periodontal Disease as a Possible Risk Factor for Complications During Pregnancy and Childbirth
Pregnancy is a physiological state that is part of the reproductive life of women,
establishing their fertile age between 15 and 45 years mainly. This stage will not only mark
the birth of the baby but also cause various changes both immunological and physiological, to
accommodate the growing fetus.
Maternal periodontitis has direct and indirect potential to influence the health of the
fetus-maternal unit. According to the literature reviewed, the first evidence that oral
bacteria influenced pregnancy outcomes was reported by Collins et al. The injection of P.
gingivalis into pregnant hamsters caused intrauterine growth retardation and smaller fetuses,
together with an increase in the levels of proinflammatory mediators (IL-1b and PGE2) in the
amniotic fluid.
Two hypotheses have been pointed out regarding the link between oral health and the adverse
outcome of pregnancy. The first states that periodontal disease causes abnormal systemic
immune changes, leading to complications in pregnancy. While the second hypothesis suggests
that oral bacteria directly colonize the placenta, causing localized inflammatory responses,
resulting in prematurity and other adverse outcomes.
Pregnancy is a physiological state that is part of the reproductive life of women,
establishing their fertile age between 15 and 45 years mainly. This stage will not only mark
the birth of the baby but also cause various changes both immunological and physiological, to
accommodate the growing fetus. In Spain, according to the Spanish National Institute of
Statistics (INE), a total of 195,555 births were registered in 2017.
However the arrival of the birth sometimes has adverse results for the mother and baby, such
as low birth weight (<2500 g), premature birth (<37 weeks), growth restriction (weight for
gestational age), preeclampsia, spontaneous abortion and / or inanimate birth. Some of these
results occur together, and it is not clear if they share common mechanisms.
According to the WHO, every year around 15 million babies are born in the world before they
reach term, that is, more than 1 in 10 births. Of them approximately, one million premature
children die every year due to complications in childbirth. As well as every day about 830
women die from complications related to pregnancy or childbirth. While 75% of maternal deaths
are due, among other causes, to gestational hypertension (preeclampsia and eclampsia).
The most common risk factor associated with premature birth is the previous history of
premature birth. Other less prevalent factors are the short interval between pregnancies,
assisted reproduction procedures, multiple gestation and infectious diseases such as
periodontitis.
Maternal periodontitis has direct and indirect potential to influence the health of the
fetus-maternal unit. According to the literature reviewed, the first evidence that oral
bacteria influenced pregnancy outcomes was reported by Collins et al. The injection of P.
gingivalis into pregnant hamsters caused intrauterine growth retardation and smaller fetuses,
together with an increase in the levels of proinflammatory mediators (IL-1b and PGE2) in the
amniotic fluid.
In humans, the first clinical study of the association between adverse pregnancy outcomes and
periodontal status was a case-control study by Offenbacher et al. These authors concluded
that the woman with periodontitis presented an almost 8 times greater risk of presenting a
preterm delivery / low birth weight of the newborn than the periodontally healthy woman.
Two hypotheses have been pointed out regarding the link between oral health and the adverse
outcome of pregnancy. The first states that periodontal disease causes abnormal systemic
immune changes, leading to complications in pregnancy. While the second hypothesis suggests
that oral bacteria directly colonize the placenta, causing localized inflammatory responses,
resulting in prematurity and other adverse outcomes.
In 2013 it was reported that low birth weight, premature birth and preeclampsia were
associated with maternal periodontitis. However, this association was moderate in relation to
other studies, probably due to differences in the study population, the different means of
periodontal evaluation used and the classification of periodontal disease that was used. The
authors of this study, argued that the association of periodontitis and adverse pregnancy
outcomes are explained by two main routes, a direct one, in which the oral microorganisms and
/ or their components reach the fetoplacental unit and another indirect, in the that
inflammatory mediators circulate and impact the fetal-placental unit.
Therefore, according to the direct route, oral microbiota during pregnancy plays an important
role in adverse obstetric outcomes. A recent meta-analysis of 22 studies that included 12047
pregnant women showed, by partially analyzing the oral microbiota, that women with
periodontitis had an increased risk of preterm birth and of giving birth to a low birth
weight baby.
The indirect route has also been studied by other authors, who reported that there was a
positive association between inflammatory mediator levels of gingival crevicular fluid and
adverse outcomes of pregnancy / preterm birth, but the results should be interpreted with
caution due to heterogeneity and variability between studies However, some authors have not
shown differences in the anaerobic bacterial profile or commensals among mothers with
periodontitis, despite the fact that they observe local placental factors, such as the nature
of the inflammatory infiltrate and the slightly higher expression of COX2 in women with these
results. Adverse effects of pregnancy are related to a subclinical proinflammatory state that
could contribute to triggering premature birth. In this regard Penova et al. they did not
observe changes in the results related to pregnancy, although the severity of the periodontal
disease was significantly associated with an increased risk of babies born small for
gestational age. They highlighted that the treatment of PE in pregnancy reduces the levels of
some inflammatory mediators in the gingival crevicular fluid, improving dental parameters but
without obvious effects on the outcome of pregnancy.
;