MS drug during pregnancy: what happens to Baby's immune cells?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Diagnosis of MS or CIS (in line with the locally approved indications) * Currently pregnant with singleton pregnancy at gestational week ≤30 at enrolment * Documentation that first and second obstetric ultrasound has been conducted before enrolment during the screening period * Documentation that the last exposure to ocrelizumab occurred up to 6 months before the LMP before the woman became pregnant OR during the first trimester of pregnancy Exclusion Criteria: * Last exposure to ocrelizumab \>6 months before the woman's LMP or later than the first trimester of pregnancy * Gestational age at enrolment \>30 weeks * Non-singleton pregnancy * Received the last dose of ocrelizumab at a different posology other than per the local prescribing information * Lack of access to ultrasound pre-natal care as part of standard clinical practice * Prior or current obstetric/gynecological conditions associated with adverse pregnancy outcomes * Pre-pregnancy body mass index \>35 kg/m2 * Any concomitant disease that may require chronic treatment with systemic corticosteroids or immunosuppressants during the course of the study * Prior or current history of primary or secondary immunodeficiency, or woman in an otherwise severely immunocompromised state * Significant and uncontrolled disease that may preclude a woman from participating in the study * Women with known active malignancies or being actively monitored for recurrence of malignancy including solid tumors and hematological malignancies * Prior or current history of alcohol or drug abuse, or current use of tobacco * Positive screening tests for hepatitis B * Treatment with drugs known to have teratogenic effects * Planned treatment with interferons, glatiramer acetate, or pulsed corticosteroids as a bridging therapy after the last ocrelizumab dose and throughout pregnancy * Treatment with disease-modifying therapies for MS within their respective half-lives prior to the last ocrelizumab dose or prior to the LMP * Treatment with natalizumab within 12 weeks prior to the LMP * Treatment with teriflunomide within the last two years, unless measured plasma concentrations are \<0.02 mg/L. If levels are \>0.02 mg/L or not known, an accelerated elimination procedure is required * Treatment with any investigational agent within 6 months or five half-lives of the investigational drug prior to the last ocrelizumab dose or prior to the LMP