Sildenafil in Sever Intrauterine Growth Retardation (IUGR)

Severe fetal growth restriction (FGR) complicates approximately 0.4% of pregnancies and severely increases the risk of perinatal morbidity and mortality.Sildenafil citrate may offer a potential therapeutic strategy to improve uteroplacental blood flow in IUGR pregnancies.

The aim of our study is to evaluate the effect of sildenafil citrate therapy on severe early and late onset intrauterine growth retardation.A total of 46 patients with severe early onset intrauterine growth retardation will be enrolled in a prospective case control study . Patients will randomly be allocated to two groups with 23 patients in each group.Sildenafil citrate therapy may increase the likelihood of increased growth velocity [measured by abdominal circumference (AC) (ultrasound)] for fetuses of pregnancies complicated by severe early-onset IUGR .Sildenafil is a potent and selective inhibitor of cGMP-specific phosphodiesterase type 5 (PDE5), which is responsible for degradation of cGMP which results in increased levels of cGMP, leading to smooth muscle relaxation. Placental disease, consequent on deficient uteroplacental blood flow, includes FGR, pre-eclampsia, and placental abruption and has been implicated in more than 50% of iatrogenic premature births .For this reason, the problem of severe FGR forms a substantial portion of the population that tertiary care centres care.

A total of 46 patients with severe early onset intrauterine growth retardation will be enrolled in a randomized placebo control controlled study . Patients will randomly be allocated to two groups with 23 patients in each group

We will offer Sildenafil citrate (20 mg per os three times daily until delivery) as innovative therapy to 23 women with severe IUGR ('Sildenafil-treated') in addition to fish oil and zinc supplementation.

Placebo tablets similar to Sildenafil will be given to control group in addition to fish oil and zinc supplementation.

Women in the Sildenafil-treated group will be also monitored for adverse side-effects, such as flushing, lightheadedness and visual disturbance

Inclusion Criteria: • pregnancy complicated by severe IUGR [abdominal circumference (AC)< 5th percentile] the gestational age <25 weeks or an estimate of the fetal weight was <600 gm (excluding known fetal anomaly/syndrome and/or planned termination) ( von Dadelszen.et al;2011). Exclusion Criteria: known aneuploid anomaly, syndrome congenital infection. If there is a plan to terminate the pregnancy.

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Lausman A, Kingdom J; MATERNAL FETAL MEDICINE COMMITTEE. Intrauterine growth restriction: screening, diagnosis, and management. J Obstet Gynaecol Can. 2013 Aug;35(8):741-748. doi: 10.1016/S1701-2163(15)30865-3. English, French.

Lee MJ, Conner EL, Charafeddine L, Woods JR Jr, Del Priore G. A critical birth weight and other determinants of survival for infants with severe intrauterine growth restriction. Ann N Y Acad Sci. 2001 Sep;943:326-39. doi: 10.1111/j.1749-6632.2001.tb03813.x.