A 24 week pregnancy scan showed frontal facial fetal defects suggestive of Moebius syndrome. Which of the following could account for the teratogenic effects?
High-Yield Explanation
Misoprostol is a methyl ester prostaglandin E1 analogue used for cervical ripening and first trimester aboion. The first trimester exposure to Misoprostol might lead to the development of Moebius syndrome. Mifepristone (RU - 486) is a potent progesterone receptor antagonist which is used in first trimester aboion and as a post-coital contraceptive. The most common side effects are vomiting, giddiness, pain or cramps, weakness and headache. Dinoprostone is a PGE2 analogue used in cervical ripening along with misoprostol. There exists a risk for the patient to develop uterine rupture. Methotrexate is a analogue of folic acid and it prevents the synthesis of DNA by inhibiting the enzyme dihydrofolate reductase. It is used in medical termination of pregnancy, medical management of ectopic pregnancy, prophylactic chemotherapy of hyatidiform mole and also in the treatment of placenta accreta. The commonly repoed side effects are leukopenia, thrombocytopenia, bone marrow aplasia, ulcerative stomatitis, hemorrhagic enteritis, elevated liver enzymes, alopecia, pneumonitis and diarrhea. Ref: Berek and Novak's Gynecology, Issue 935, Volume 2007 By Emil Novak, Page 622; Syndromes of the Head and Neck By Robe J. Gorlin, Meyer Michael Cohen, Raoul C. M. Hennekam, Page 826; Pediatric Ophthalmology, Neuro-Ophthalmology, Genetics: By Birgit Lorenz, Michael C. Brodsky, Pages 70-71; Merritt's Neurology By Lewis P. Rowland, Timothy A. Pedley, Hiram Houston Merritt, Page 602