Primary Objective:

To evaluate any potential increase in the risk of major birth defects, in the first year of life, in teriflunomide-exposed pregnancies.

Secondary Objective:

To evaluate the potential effect of teriflunomide-exposure on other adverse pregnancy outcomes including any potential pattern of minor birth defects, spontaneous abortion, stillbirth, preterm delivery, small for gestational age at birth and at 1 year follow-up.

The total study duration per participant is approximately up to 2 years.

• This is a prospective, observational study (no intervention), ie, patient registry.
• The statistical analysis for the cohort study describe baseline characteristics in all three cohorts, and then will compare pregnancy outcomes in cohort 1 to cohort 2 and secondarily to cohort 3.
• For the "registry" group, without comparisons, only descriptive statistics of pregnancy outcomes will be summarized.

Inclusion criteria :

• Pregnant women who have provided an oral and/or written consent to enroll no later than 20 completed weeks from last menstrual period (LMP).
• Pregnant women who agree to the conditions and requirements of the study including the interview schedule, release of medical records, and the physical examination of live born infants (up to 1 year post birth).
• Pregnant women with a diagnosis of MS and teriflunomide exposure during pregnancy (Cohort 1).
• Pregnant women with MS but not exposed teriflunomide during pregnancy (Cohort 2).
• Healthy pregnant women who do not have a known diagnosis of MS and have no known exposure to a known human teratogen during pregnancy (Cohort 3).

Exclusion criteria:

• Pregnant women who come in first contact with the project after prenatal diagnosis of a major structural defect (Cohort 1, 2, 3). This does not apply to the "registry" group.
• Pregnant women who first come in contact with the project after 20 completed weeks' gestation (Cohort 1, 2, 3). This does not apply to the "registry" group.
• Pregnant women who had previously enrolled in the study for a previous pregnancy (only 1 pregnancy, per woman, maybe registered) (Cohort 1, 2, 3). This does not apply to the "registry" group.
• Retrospectively reported cases (Cohort 1, 2, 3). This does not apply to the "registry" group.
• Pregnant women with exposures to teriflunomide commencing after the 12th week post-LMP (Cohort 1). This does not apply to the "registry" group.
• Pregnant women who had previously been treated with teriflunomide if they had received any dose of the drug within 2 years prior to the index pregnancy and do not have documented blood levels below 0.02 mcg/mL prior to pregnancy (Cohort 2).

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

-Pregnant women will be enrolled at various stages of gestation depending when they are included in the registry; then the pregnant outcome will be followed and for live infants, the follow up will be up to the children's 1 year birthday.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org