Effects of topiramate administration on placenta of rat

Background: Topiramate was classified as pregnancy category D, which means that it possesses a potential risk to the fetus. An increasing evidence points to the risk of development of cleft lip and/or cleft palate [oral clefts] in infants born due to Topamax [topiramate] during pregnancy

Objective: To evaluate the effects of the therapeutic doses of topiramate on the placental structure

Design: An Experimental Animal Study

Setting: Teratology Laboratory, Anatomy Department, CMMS, Arabian Gulf University

Method: Pregnant rats were treated with oral topiramate at doses of 50 and l00mg/Kg body weight. On day 20, the pregnant rats were sacrificed, and the placentae were collected and processed for histological evaluation

Result: Degenerative changes in all three layers of the placenta [decidual, basal and labyrinthine] were observed. In the decidual layer, deposition of fibrous and hyaline materials were found in the cells, in addition to vacuolization and hemorrhages. In the basal layer, the trophoblast cells [giant, basophilic and glycogen cells] showed vacuolization, cytolysis and cyst formation. In the labyrinthine layer, there was an increased fibrinoid material and fetal mesenchyme. In addition, degeneration of cells and congestion of blood vessels were evident

Conclusion: The deleterious effects of the therapeutic doses of topiramate on the placental structure may play a role in its teratogenicity. These placental changes are not dose dependent

Effects of topiramate on pregnancy outcome in rats

Background: Anti-epileptics taken during pregnancy might lead to low birth-weight and birth defects which could be associated with neonatal morbidity and mortality

Objective: To evaluate the effects of maternal exposure to therapeutic doses of topiramate on the growth of 20-day rat fetuses. Design: An Experimental Animal Study. Setting: Teratology Laboratory, Anatomy Department, College of Medicine and Medical Sciences, Arabian Gulf University, Bahrain

Method: Three groups of Sprague-Dawley pregnant rats were used in the experiment: control, Topiramate 50mg/Kg BW and Topiramate 100 mg/Kg BW. Topiramate was administered by intragastric intubation from day 6 through day 19 of gestation. Cesarean section was performed on day 20. Resorption was calculated, placental weight and umbilical cord length were measured. Fetuses were collected to assess their growth parameters: fetal weight [FW], biparietal diameter [BPD], crown-rump length [CRL] and head length [HL]. Ponderal index and CRL/HL ratio were calculated to indicate the type of growth restriction

Result: The Topiramate treated groups showed an insignificant increase in the rate of resorption, a significant decrease in umbilical cord length, placental weight and highly significant reduction in fetal growth parameters. No significant changes were noticed in fetal growth parameters between Topiramate groups. A positive correlation was found between FW and UCL, PW, CRL, HL and BPD in all examined groups. Ponderal index and CRL/HL ratio indicate symmetrical growth restriction of the fetuses in both treated Topiramate groups

Conclusion: The doses of Topiramate, which were given to pregnant rats were equivalent to the human therapeutic range; the drug led to symmetrical fetal gross restriction with few abnormal fetuses and placentae. Topiramate attributed effects were not dose related. The drug should be taken with caution during pregnancy

Facial anthropometry in an Arab population

To measure the inter-alar width of the nose, the maxillary inter-canine distance and mouth width of an Arab sample and evaluate the ethnic variations. A prospective study. College of Medicine and Medical Sciences, Arabian Gulf University, Bahrain. One hundred sixty-eight young adult Arab subjects [51 males and 117 females], from five countries of the Gulf Cooperation Council [GCC], were selected randomly from undergraduate medical students during the academic year 2009/2010. Mouth, nose and teeth dimensions were measured using Vernier caliper; for each subject, three measurements were taken and the average was recorded. The mean inter-alar width of the nose was 35.06 mm [37.14 mm in males and 33.21 mm in females]. The mean maxillary inter-canine distance was 37.96 mm [39.66 mm in males and 36.38 mm in females]. The mean mouth width was 50.66 mm [52.85 mm in males and 48.63 mm in females]. The maxillary inter-canine distance was 75% of mouth width; therefore, the mouth width is a reliable predictor of the maxillary inter-canine distance and vice versa in the Arab population. Comparison between nationals from different GCC countries showed that Bahraini males had significantly wider mouths than Saudi Arabian males [P=0.034]. GCC Arab males had significantly wider noses, broader maxillary arches and wider mouths than females [P<0.001]. Anterior maxillary arches were found to be wide in males and females, which seems to be an ethnic characteristic in Arabs of this region