Prevention
Chronic
hypertension is more common after pre-eclampsia, affecting about 15% at
2 years. It is more likely after eclampsia or severe pre-eclampsia (especially
if recurrent or occurring during the 2nd trimester), affecting 30-50% of
women.
Many trials of different drugs &
supplements have been carried out to try & prevent this disease.
Fish oil (halibut liver oil) in one trial has been suggested to marginally
reduce the incidence of pre-eclampsia. The study that demonstrated this
dates back to 1946 & subsequent trials have not been as promising.
In addition, there are concerns about side effects with excessive supplementation
with fish-oils (bleeding tendency & fall in platelet count).
Increased
dietary protein has been suggested to reduce the incidence of pre-eclampsia,
but review of the published literature by the World Health Organization
Expert Committee on Pregnancy and Lactation concluded that in the absence
of any established deficiency, supplementation is unlikely to change a
woman's chance of developing pre-eclampsia.
Calcium
supplementation has also been suggested; indeed, summation of several smaller
trials definitely pointed to a reduction in blood pressure complications
in those who took calcium supplements. In July 1997 in the New England
Journal of Medicine a paper was published
from the National Institutes of
Health in the US. They enrolled almost 5000 women, half of whom received
calcium supplements. Unfortunately, there was no difference in pre-eclampsia
between the two groups. Read the article: http://www.infopoems.com/POEMs/JC109702.htm
A
large trial of low-dose aspirin has confirmed that it has a place in prevention
of pre-eclampsia. This multi-centre study which was published in 1994 demonstrated
that the only group of women shown to benefit from aspirin were those deemed
to be at risk of severe early pre-eclampsia - i.e. those in whom it had
occurred before. Aspirin made no difference to any other group treated.
Also no effect on proteinuric hypertension,
fetal growth, pre-term birth. Anaheim Results of a large U.S. Institutes
of Health study confirm previous reports that low-dose asa does not reduce
the incidence of pre-eclampsia in high-risk patients and also indicates
the medication has no effect on proteinuric hypertension, pre-term birth
or fetal growth. The results were reported by Steve Caritis, MD, during
a meeting of the Society of Perinatal Obstetricians, here. He is
professor of obstetrics and gynecology at the University of Pittsburgh.
The study's population of 2503 patients were grouped according to four
high risk categories: history of diabetes (n = 462), multifetal gestation
(678), history of pre-eclampsia (600) & chronic hypertension (763).
Each was randomized to receive either asa 60mg or placebo during weeks
13 - 26 of their pregnancies. "If you look at our patient population,"
said Dr. Caritis, "we studied most of the women who are going to walk into
a doctor's office.
There may be some benefit
that we haven't identified, but somebody would have to identify a different
subset of patients." Critics of previous studies have contended that the
patients in those trials did not represent high-risk patients. Results
of the NIH study should end such comments.
"The overall risk of pre-eclampsia
is about five per cent," Dr. Caritis noted, "but in the high-risk patient
categories we evaluated, the risk might be as high as 20 per cent. There's
no question that these patients were at high risk for complications." Primary
outcome in the study was proteinuric hypertension defined as two blood
pressure measurements of 140/90mm Hg or higher at least four hours apart
and proteinuria of at least 300mg/day or 2-plus by dipstick measurement.
Secondary endpoints were pre-term birth, fetal growth restriction and bleeding
complications. asa produced no statistically-significant effect on the
primary endpoint for any of the sub-groups and the total patient population.
The largest difference noted by the investigators was in the multifetal
gestation group where patients treated with asa had an 11.5 per cent incidence
of proteinuric hypertension compared with 15.9 per cent with placebo.
Percentage Ranges.
Diabetic patients who received asa
had an 18.3 per cent incidence of proteinuric compared to 21.6 per cent
for placebo. The respective percentages were 16.7 and 19 per cent among
patients with histories of pre-eclampsia and 26 and 24.6 per cent for the
chronic hypertensives. This group also recorded the largest difference
in the incidence of pre-term births, 30.7 per cent for asa-treated women
and 35.9 percent among the placebo patients. The incidence among the groups
ranged from 24 per cent for women with a history of pre-eclampsia to 68
percent in the multifetal gestation group.
The diabetic patients accounted
for the largest difference in fetal growth retardation; it was 5.3 per
cent among asa users and 3.1 per cent for those on placebo. The difference
among the four groups straddled a low of four per cent (diabetics) and
10 per cent (multifetal gestation).
The results presented by Dr. Caritis
are similar also to those from recent large studies in Jamaica and Barbados,
said Baha Sibai, MD, principal investigator of the 1993 nih trial. "This
study closes the door on the use of asa for the prevention of pre-eclampsia,"
he said. "These were truly high risk patients, and if asa were beneficial,
you would have expected to see a benefit in these patients. Clearly there
was no advantage to asa therapy in any of the patient subgroups."
One
new bit of therapy is the use of Vitamins C&E to help avert PIH.
You can read the article at http://www.bergen.com/healthw/pregnanc199909034.htm
Also,
there are a variety of tests that a competent OB can carry out to help
detect and problems that are arising. A liver function test and platelet
level blood test should be periodically performed in a woman going through
a pregnancy after having HELLP.
Also hopefully before you get pregnant
after having HELLP you had testing done to make sure you didn't have any
underlying autoimmune disorders such as Lupus, Non-Lupus or other platelet
or blood disorders.
Still
looking for more HELLP information? If you have a HELLP story to
share please stop by the HELLP
Syndrome Birth Stories Page and leave or read a story. Here you
will also find up to date HELLP/Pre-E net articles and books. You
wil also find WebRing information at the above listed url.
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