Endocrine/Metabolic Agent (Prostaglandin)
PREGNANCY RECOMMENDATION: First 28 Weeks of Pregnancy—Contraindicated Unless for Termination/Evacuation of Pregnancy Near or At Term—Compatible
BREASTFEEDING RECOMMENDATION: No Human Data—Probably Compatible
PREGNANCY SUMMARY
No reports describing human pregnancy outcomes following use of dinoprostone in failed medical abortions have been located. In animals, prostaglandin E2 exposure has resulted in embryotoxicity and an increase in skeletal anomalies. Another prostaglandin analog, misoprostol, when used unsuccessfully in the 1st trimester as an abortifacient, has been associated with cranial nerve defects in the fetus. Use of dinoprostone for cervical ripening near term has not been associated with an excess of adverse outcomes for the infant.
FETAL RISK SUMMARY
Dinoprostone is a naturally occurring prostaglandin E2 that is available in vaginal suppository form and is used for induced abortion between 12 and 20 weeks’ gestation, for evacuation of uterine contents in the case of missed abortion or intrauterine death up to 28 weeks’ gestation, and in the management of benign hydatidiform mole. Dinoprostone is also available as a controlled-release vaginal insert and in gel form, and is used for cervical ripening in term or near-term pregnancies. Dinoprostone, when given as a vaginal suppository, functions to stimulate the myometrium of the uterus to contract. Dinoprostone has a short half-life of 2.5–5 minutes (1,2).
Reproductive studies have been conducted with prostaglandin E2 in rats and rabbits. In both species given the agent during organogenesis, embryotoxicity and fetal skeletal variations were observed (1,2).
No carcinogenicity or fertility studies have been conducted for dinoprostone. No evidence of mutagenicity was observed in the various assays (1,2).
It is not known if prostaglandin E2 crosses the placenta. The molecular weight (about 352) suggests that exogenous prostaglandin E2 will cross the placenta. However, the indicated uses for the drug and the very short elimination half-life (2.5–5 minutes) suggest that little drug may actually cross to the embryo–fetus (1,2).
No reports describing the outcomes of human pregnancies following the use of dinoprostone in failed medical abortions have been located. Although a failed attempted abortion would typically be followed by completion of the procedure by some other means, in rare cases a woman may wish to maintain the pregnancy. Isolated case reports suggest that the failed procedure(s) themselves may result in damage to the placenta and therefore damage to the fetus (3). First trimester exposure to another prostaglandin, misoprostol, in failed induced abortion, has been associated with an increased risk for 6th and 7th cranial nerve damage leading to Möbius’ syndrome (see Misoprostol). However, in the case of dinoprostone, the most common use of the product would be after the first trimester.
BREASTFEEDING SUMMARY
No reports describing the use of dinoprostone during human lactation have been located. The molecular weight of dinoprostone (about 352) suggests that it will be excreted in breast milk. However, the local use of the product and the very short elimination half-life (2.5–5 minutes) suggest that clinically significant amounts will not be present in milk (1,2).
References
1.Product information. Cervidil. Forest Laboratories, 2011.
2.Product information. Prostin E2. Pfizer, 2006.
3.Arnon J, Ornoy A. Clinical teratology counseling and consultation case report: outcome of pregnancy after failure of early induced abortions. Teratology 1995;52:126–7.