Wednesday, June 20, 2007

Study hopes to find if asprin can aid pregnancy

When a woman has a miscarriage, she's often told it was "meant to be."

But what if it's not -- and what if taking one children's aspirin a day could help her have a baby?

University of Utah researchers hope to find the answer. As part of a national study, they will be looking at whether low-doses of the widely-available drug can help women who have previously had a miscarriage.

Investigators believe aspirin will help thicken the uterus lining, improving the odds an embryo will be implanted. They also think it will increase blood flow to the placenta, providing oxygen and nutrients to keep the fetus healthy and alive.

Besides trying to help women get and stay pregnant, the years-long study involving 1,600 women from Utah and New York could shed more light on fertility -- a basic human experience that receives relatively little attention by researchers.

"We often just never study pregnant women so we know less about it than we know, say, about heart attacks," said Robert Silver, the university's principal investigator and an ob-gyn who specializes in high-risk pregnancies.

"It's really remarkable how little is known."

The American College of Obstetricians and Gynecologists say miscarriage -- defined as losing a pregnancy before the 20th week -- is the most common reproduction problem.

Researchers estimate it happens in 15 percent of known pregnancies, and they suspect it happens much more frequently -- in up to 31 percent of cases -- because it can occur before the woman even knows she is expecting.

After one miscarriage, women have about the same chance of having a successful pregnancy as other women. But after two losses, her risk of another increases by around 25 percent. And after three, the chance jumps approximately 35 percent.

That's why it's important to know the cause, but doctors can't say half the time.

The study, dubbed the Effects of Aspirin in Gestation and Reproduction, or EAGeR, aims to help and is funded by the National Institute of Child Health and Human Development. Participants must be trying to get pregnant and have had one previous miscarriage. The women will be randomly selected to take 81 milligrams of aspirin a day or a placebo. All will take folic acid.

"This is a low-cost, easily available treatment that may be able to help maintain and prevent unnecessary losses," said Enrique Schisterman, the principal investigator at the Maryland-based federal agency.

Silver suspects -- and the study could help confirm -- that most miscarriages that occur before eight weeks are due to genetic errors as the embryo develops. Those problems can't be helped. "It's nature's way of taking care of a pregnancy that couldn't survive," he said.

The pregnancy losses that happen later could more likely be due to blood flow, Silver predicts. Researchers hope to know for sure by examining ultrasounds, blood tests and placenta and fetal tissue from the study participants.

Some doctors already advise women to take low-dose aspirin if they have suffered multiple miscarriages. That's because aspirin has helped women prone to blood clots get pregnant, Silver said. In addition, some data shows that aspirin improves the pregnancy rates by 16 percent among women undergoing in-vitro fertilization, Schisterman said.

The two researchers say aspirin could also reduce the risk of high blood pressure during pregnancy, called preeclampsia, prevent preterm labor and help fetuses fully grow.

"The main outcome of the trial will be miscarriage, but we hope to see effects in later pregnancy as well," Schisterman said.

While other studies have not shown aspirin to help women with previous miscarriages, the drug was used by women after they became pregnant, Schisterman said. This study is different because women will start taking aspirin before they conceive. Studies have shown low doses of aspirin do not harm fetuses, the researchers said.

Participants will be keeping a daily diary, tracking their menstrual cycles, sexual activity, stress levels and diet. They will also provide daily urine samples for a couple of months, frequent blood samples, and have multiple ultrasounds. All that data will give researchers better insights into pregnancy using a larger population than has been studied in the past.

They will learn about the process of embryo implantation, what proportion of women get pregnant when they're trying, and how the mother's immune system works during pregnancy and why it doesn't reject the fetus, which her body considers a foreign object.

"We're going to be able to learn a lot even if the aspirin doesn't work," Silver said.

The urine and blood samples could eventually lead to new tests to predict who will have miscarriages or pregnancy complications, he added.

The results won't be available for three more years.



Anonymous said...

Did you read anywhere where they said what does to take? I have heard of the asprin therapy also but do not know the dosage.

Catherine McDiarmid-Watt said...

The dosage is 81mg/day - commonly sold as "low-dose" aspirin.