Teratogenic effect of the aqueous extract of the Foeniculum vulgare (fennel) on fetal development in mice

Objective The present study evaluated the effect of aqueous extract of Foeniculum vulgare on fetal development in pregnant mice models. Methods A total number of 24 female BALB/c mice with a weight range of 25-30 gr divided into four groups. Each group received 0.25 ml of the aqueous extract of Foeniculum vulgare with different concentrations (2.5 mg, 12.5 mg, 25 mg) and distilled water as a control group. The aqueous extract of Foeniculum vulgare administered via oral gavage on a daily basis from day 6 to day 15 of pregnancy. On day 16, the fetuses were analyzed in terms of morphological changes, skeletal disorders, and cellular alterations. Results The result showed the dose-dependent teratogenic effect of the aqueous extract of Foeniculum vulgare. At 12.5 mg and 25 mg concentration, the teratogenic effect was more severe. Oral gavage administration of the aqueous extract of Foeniculum vulgare increased the number of dead fetuses and reduced the average weight, height, and crown-rump length. Subcutaneous hemorrhage, dorsal lesion, wrinkled skin, and considerably lower than normal fetal weight observed in gross morphological inspection at 25 mg concentration. The skeletal studies revealed fetal anomalies, reduction in ossification and reduction in the number of ribs. Internal bleeding around the liver and lungs, pulmonary fibrosis and disruption in the arrangement of hepatocytes was also observed in histological analysis. Conclusion Administration of the aqueous extract of Foeniculum vulgare results in embryotoxicity in mice models in morphological, skeletal and cellular levels. Keywords Foeniculum vulgare, Fennel, Teratogenicity, Embryotoxicity, Fetal Development, Mice