Which statement about magnesium sulfate in preterm labor is true?

• A. It stimulates fetal lung maturation
• B. It stops preterm labor and can act as an anticonvulsant in preeclampsia
• C. It treats ectopic pregnancy
• D. It promotes surfactant production

Answer: (B)

Magnesium sulfate serves two main roles in obstetrics: it can relax the uterus to help slow or stop preterm contractions, and it acts as an anticonvulsant to protect the mother in preeclampsia/eclampsia. The tocolytic effect gives time for fetal maturation, and the anticonvulsant effect helps prevent seizures. It is not used to promote fetal lung maturation (that’s steroids like betamethasone) and it does not treat ectopic pregnancy or promote surfactant production. So the statement that it can slow preterm labor and act as an anticonvulsant in preeclampsia is true.