 |
| fda.gov |
Antiplatelet agents(Aspirin) reduce spontaneous preterm birth(PTBs) in
pregnant women at risk for preeclampsia according to a study published in February issue of Journal of Obstetrics and Gynecology.
This is an
additional analysis of data from The Perinatal Antiplatelet Review of
International Studies Individual Participant Data meta-analysis which showed
moderate reduction in risk of preeclampsia (relative risk [RR] 0.90, 95%
confidence interval [CI] 0.84–0.97).
Preterm
birth(PTB) is the birth of an infant before 37 weeks of pregnancy, according
to WHO
statistics an estimated 15 million babies born preterm out of whom 1
million succumb. PTB is also responsible for long term neurological
complications in children like cerebral palsy, learning disabilities and visual
and hearing problems.
The current
global preterm birth rate is 5% to 18% and statistic shows a steady increase
recently. More than 60% of preterm births occur in Africa and South Asia, India
topping the list with 3 519 100 PTBs.
Three forth
of these births could be prevented, saving lives and money across the globe. History of uterine evacuation is an independent risk factor for preterm birth.[1]
Other risk factors for PTBs are Myometrial contractions, mother's cervicovaginal microbiota and Intrauterine
infections. Myometrial contractions are triggered by interplay between
mechanical, endocrine and immune factors. Increasing body of evidence suggests
that uteroplacental ischemia could play an important role in bringing on
preterm births similar to its role in preeclampsia.
The evidence
comes from examining the placental tissues in women with spontaneous PTBs. At
least one third biopsies depicted placental vascular pathology in terms of
failure of physiological transformation of spiral arteries as seen in
preeclampsia.
Keeping in
view the similar pathologies for PTBs and preeclampsia the authors wanted to
know whether aspirin could prevent iatrogenic as well as spontaneous preterm
births.
After
excluding the women who did not meet the study criteria, 27,510 women were
randomized to receive low dose aspirin vs. Placebo. These women were at low to
moderate risk for developing preeclampsia.
Low dose aspirin
was started between 16- 20 weeks
depending upon the gestational age upon entering into the studies.
The study
was evaluated based on 3 primary endpoints: spontaneous preterm birth at <
37 weeks, < 34 weeks, and < 28 weeks of gestation.
Antiplatelet
agent (Aspirin) significantly reduced the risk of PTBs by 7%. PTBs before 34
weeks were reduced by 14%. The study did not find significant reduction in
preterm births before 28 weeks of gestation. It may be because of lack of power
in that subgroup or pathologies other than placental ischemia may play a role
in very early PTBs.
Incidence of
antepartum hemorrhage, placental abruption or neonatal bleeding remained the
same for the two study arms. Slight higher incidence of PPH was seen in aspirin
group, but was not statistically significant.
The
administration of antiplatelet agents such as aspirin during pregnancy is
considered a safe intervention as a recent review commissioned by the U.S.
Preventive Services Task Force concluded.
The authors
concluded “The current findings might be applicable to a broader population of
pregnant women. Because there is a paucity of preventive strategies for
spontaneous preterm birth, we suggest that the use of antiplatelet agents may
be a promising intervention for women who have a history of spontaneous preterm
birth.” They further added “The current study provides clinicians with the best
available evidence to counsel women regarding who might benefit from this
intervention.”
Full text of the article can be accessed here.
No comments:
Post a Comment