Effects of Laurus nobilis on pregnancy and fetal growth using pregnant Sprague-Dawley

Background: Pregnancy-related nutritional choices significantly affect maternal reproductive health and fetal health. Laurus nobilis is widely used worldwide as a food-medicinal herb, even among pregnant women; however, its effects on the health of pregnant women and fetuses are underexplored. This study investigated the effects of L. nobilis on pregnancy and fetal growth in Sprague-Dawley rats. Methods: Twenty-four pregnant rats were randomly assigned to four groups: control, low dose (50 mg/kg), medium dose (100 mg/kg), and high dose (200 mg/kg) of the herb. Animals were sacrificed after 19 days after oral administration of L. nobilis. Body weight, number of litters, and weights of the uterus, ovary, and litter were measured. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and progesterone were determined using ELISA. Histological analyses of the ovaries and uteri were performed. Results: The increase in body weight was highest in the control group (+38.0%) and significantly lower in the treatment group. Ovary weights did not differ significantly across groups, but uterus weight was markedly lower in the high-dose group compared to the control. The number of litters and litter weights decreased with increasing L. nobilis doses. Serum FSH, LH, and progesterone levels were significantly reduced in the treatment groups. Superoxide dismutase and catalase expression levels revealed a dose-dependent decrease, whereas malondialdehyde levels increased. Histological examination revealed dose-dependent alterations in the ovaries and uteri. Conclusion: These findings suggest that L. nobilis consumption during pregnancy may adversely affect maternal health, fetal growth, and reproductive hormone levels in a dose-dependent manner. The mechanisms underlying these effects need to be elucidated, and the safety of L. nobilis consumption during pregnancy in humans needs to be determined.