What Are The Effects Of Ibuprofen On Pregnancy?

Most pregnant women worry about the effects of taking medication on the growing fetus. When medications are available over the counter, many pregnant women assume that they're safe to use without asking a medical provider. But many over-the-counter medications such as ibuprofen have significant risks when taken during pregnancy, especially when taken in the last three months of pregnancy, a time when many women feel that it's safer to take medications.

Premature Closure of the Ductus Arteriosus

Ibuprofen belongs to a class of medications called prostaglandin inhibitors, often used to close the ductus arteriosus in premature infants after birth. The ductus arteriosus, an opening from the pulmonary artery to the aorta, shunts blood away from the fetal lungs before birth. After birth, when blood flows through the lungs for the first time and the pressures within the blood vessels changes, the ductus arteriosus closes.
In premature infants, the ductus may not close after birth, resulting in a decrease in oxygen supply to the body. Ibuprofen or indomethacin, a similar drug, is used to close the ductus. When taken after 30 weeks in pregnancy, ibuprofen may cause premature closure of the ductus, which affects fetal circulation. The incidence and degree of closure appears to be dose related, the National Teratology Information Service reports.

Decrease in Amniotic Fluid

"Bonica's Management of Pain," published in 2009 by Jane C. Ballantyne, reports that women who take ibuprofen to stop preterm labor in the second half of pregnancy had a decrease in the amount of amniotic fluid that cushions the fetus. Decreased renal function results in a decrease in fluid, called oligohydramnios. Oligohydramnios can cause poor fetal growth and possible problems during labor and delivery, according to the March of Dimes.

Birth Defects

There's debate about whether taking ibuprofen in early pregnancy causes birth defects. Two studies have shown that taking ibuprofen in the first three months of pregnancy slightly increases the risk of gastroschisis, a congenital birth defect where the intestines extrude from a small opening near the umbilicus, the Organization of Teratology Information Specialists states. The risk may increase from 1 in 10,000 births to 1.6 to 4 in 10,000 births, the organization states. Three other studies showed a slight increase of risk of heart defects when ibuprofen was taken in early pregnancy

Inhibition of Labor

Ibuprofen is sometimes used to stop premature labor. When taken in the last month of pregnancy, ibuprofen may also inhibit the start of labor, the Organization of Teratology Information Specialists states.