Hypothetical Role of Prostaglandins in the Onset of Preterm Labor after Fetal Surgery

Abstract

Preterm labor is one of the most important factors limiting the advancement of fetal surgery programs. While prostaglandins (PGs) have long been indicated as the key factor in the initiation of labor in humans, there is significant evidence showing that the chorionic membrane acts as a powerful barrier between the decidua/myometrium and amniotic PGs during normal pregnancy. After either open or endoscopic fetal surgery the imperfect, non-hermetical closure of the chorion permits leakage of PGs from the amnionic sac, allowing them to reach the decidua and myometrium. The surgical wound in the chorionic barrier could be the major factor involved in preterm labor and delivery after human fetal surgery.

Alternative Hysterotomy Technique for the Reduction of Prenatal Complications of Intrauterine Myelomeningocele Repair

“…The meta-analysis by Kabagambe et al [11] evaluating the results of 11 cohort studies performed with fetoscopic versus an open approach showed higher rates of PPROM (91 vs. 36%, p < 0.01) and PTL (96 vs. 81%, p = 0.04) for the endoscopic technique. These results remain consistent with the hypothesis of Pommini et al [12], who suggested that even a small area of disruption of the myometrium and fetal membranes, in the endoscopic technique but with limited wound closure, causes AF infiltration with high amounts of PGs to the myometrium stimulating contractions. Persistent myometrium contractility causes an increase in the AF pressure leading to the increase in AF leakage to the chorionic space, resulting in CMS, PPROM, and PTL.…”

Reversible Ductus Arteriosus Constriction due to Maternal Indomethacin after Fetal Intervention for Hypoplastic Left Heart Syndrome with Intact/Restrictive Atrial Septum

“…Repeat fetal echocardiography 24 h after the diagnosis of ductal constriction revealed the DA to be widely patent with normalization of Doppler indices and cardiac function. Prematurity and associated premature rupture of membranes remain significant limitations to open and fetoscopic fetal intervention [32] , although this has not been a major issue in percutaneous FCI such as the procedures performed in these cases. The incidence of DA constriction after the use of indomethacin may be higher in fetuses with more advanced gestational age, but indomethacin remains very effective in achieving uterine quiescence following direct uterine puncture [2,3,10,32] .…”

“…Prematurity and associated premature rupture of membranes remain significant limitations to open and fetoscopic fetal intervention [32] , although this has not been a major issue in percutaneous FCI such as the procedures performed in these cases. The incidence of DA constriction after the use of indomethacin may be higher in fetuses with more advanced gestational age, but indomethacin remains very effective in achieving uterine quiescence following direct uterine puncture [2,3,10,32] . When considering the use of indomethacin for tocolysis following fetal interventions, it is important to weigh the risks of prematurity against the benefits of utilizing an effective agent for which side effects appear to be reversible.…”

Current Status of Fetal Cardiac Intervention

“…This delineation is based on reports that preterm labor occurs in 80% of fetal surgical procedures in which a single 10F (3.3 mm) port is used and almost universally with larger ports or incisions. 37 …”