Sildenafil citrate, the active ingredient, has been found to have applications other than the treatment of impotence.

Viagra, the little blue pill that revolutionized the treatment of impotence worldwide, is now being studied for possible use in pregnant women who are suffering from intrauterine growth restriction, or IUGR.

IUGR is a condition in which an unborn baby is not developing at the normal rate within the womb, according to WebMD. This retardation of fetal growth can cause problems both during the late stages of pregnancy or after birth. In its most extreme form, IUGR can lead to stillbirth.

Promotes Strong Blood Flow

In its treatment of impotence, Viagra works by stimulating strong blood flow to the penis, which is essential to achieve and maintain an erection strong enough and long lasting enough for intercourse.

Preliminary studies have indicated that the little blue pill also can promote increased blood flow to the placenta and thus help babies who are not growing properly to increase their weight.

Left untreated, IUGR can lead to a host of problems that may show up during pregnancy, delivery, or after birth. According to WebMD, these problems include low birth weight, difficulties handling the stress of vaginal delivery, decreased oxygen levels, low blood sugar (hypoglycemia), reduced resistance to infection, elevated red blood cell count, and trouble maintaining body temperature.

Other Effects of IUGR

In some cases, the unborn child may experience breathing problems because of meconium aspiration, which is the inhalation of stools passed while still in the uterus. Another possible consequence of IUGR is a low Apgar score in tests done immediately after birth to evaluate the newborn’s physical condition. A low Apgar score may mean that the newborn will need special postnatal treatment to improve his or her condition.

In addition to problems with the placenta, IUGR can develop because of certain health problems in the mother-to-be. Such health conditions include high blood pressure or heart disease, advanced diabetes, anemia or malnutrition, kidney or lung diseases, sickle cell anemia, and infections such as cytomegalovirus, rubella, syphilis, and toxoplasmosis. IUGR can also develop if the mother-to-be abuses drugs, drinks alcohol, or smokes.

International Studies

In mid-2013, researchers in Australia and New Zealand launched a multiyear study into the effects of Viagra among pregnant women who show signs of IUGR. More recently, in the fall of 2014, a two-year study was launched at Liverpool Women’s Hospital in the United Kingdom.

Viagra may help pregnant women who show signs of intrauterine growth restriction to deliver healthy babies.

In the Liverpool study, pregnant women who show signs of IUGR will be given either Viagra or a placebo three times a day until delivery. Researchers hope that the increased blood flow to the pelvic area that helps to support the erectile function in men will also help to promote fetal development by increasing blood flow and thus oxygen supply to the placenta of women given the drug.

The New Zealand study is being conducted at Auckland City Hospital and involves 120 pregnant women who have been identified as having a higher risk of having a pre-term baby. Some of the women will be given low doses of sildenafil citrate, the active ingredient in Viagra, while others will receive placebo. Researchers hope to be able to determine whether Viagra use promotes fetal growth and prevents premature delivery.

Pre-eclampsia and IUGR

Another common cause of IUGR is pre-eclampsia, a condition in which the arteries supplying the placenta fail to widen enough to deliver all the blood and oxygen the fetus needs to develop properly. Pre-eclampsia often results in pre-term delivery or even stillbirth.

Leading the New Zealand trial is Dr. Katie Groom, a senior lecturer in the University of Auckland’s Department of Obstetrics and Gynecology. In an interview with “The New Zealand Herald,†Dr. Groom said, “If we can determine a therapy that enhances fetal growth, and we can therefore delay delivery, we will improve not only these babies’ survival rates, but also reduce the many complications that follow and can lead to life-long disability or disease.”

Another participant in the New Zealand trial is Professor Phil Baker, director of Gravida National Centre for Growth and Development. Baker is credited with pioneering some of the earliest studies into sildenafil’s possible role in increasing blood flow to the uterus and fetus.

Results Due in Early 2017

Concurrent with the study at Auckland City Hospital, researchers in Australia are conducting similar testing. Results from the joint studies are expected to be released in early 2017.

Viagra may also have some beneficial effects for women who are having difficulty getting pregnant. Although there have been no large-scale studies on this phenomenon, a few isolated case studies provide at least anecdotal evidence of still more benefits from the little blue pill.

The newborns of mothers with intrauterine growth restriction often are premature or low in birth weight.

In May 2000, Mohamed Taranissi, M.D., director of a private London fertility clinic, told TheGuardian.com that a woman under his care was able to become pregnant after taking Viagra. Dr. Taranissi said, “I’m pleased, but very cautious, because we need to do this with a lot more women to get any meaningful results.â€

U.S. Successes Reported

Less than two months earlier, U.S. fertility doctor Geoffrey Sher had announced that three out of four previously unfertile women who used Viagra were able to become pregnant in a small-scale study that he conducted.

In an interview with CNN.com, Dr. Sher took pains to point out that these Viagra success stories involved women with a specific problem that was making it difficult for them to get pregnant. All had extremely thin uterine linings that prevented a fertilized egg from attaching to the uterus and developing.

Also Treats Lung Condition

In addition to its primary use in the treatment of impotence and its possible application in treating pregnant women with IUGR, sildenafil citrate, the active ingredient in Viagra, is used to treat pulmonary arterial hypertension.

PAH is a condition in which the arteries supplying the lung constrict abnormally, forcing your heart to work harder and causing the blood pressure in your lungs to increase. According to the American Lung Association, this disorder worsens over time and can become life-threatening because of the increased strain on the heart. Its symptoms include shortness of breath, fatigue, dizziness or lightheadedness, fainting, a racing heartbeat, chest pain, and swollen ankles or legs.

PDE5 Inhibitors

Sildenafil citrate, marketed under the trade name of Revatio, is a 20-milligram tablet that has been shown to be effective in the treatment of PAH. Viagra or sildenafil citrate is one of a family of drugs known as PDE5 inhibitors, so-called because they temporarily block the effects of the phosphodiesterase-5 enzyme that can interfere with blood flow to the lungs as well as the pelvic area.

In all its many applications, sildenafil citrate causes a temporary drop in blood pressure, which makes it incompatible with nitrate-based drugs that also lower blood pressure. Taken together, the two drugs could cause a life-threatening drop in blood pressure.

Don Amerman is a freelance author who writes extensively about a wide array of nutrition and health-related topics.