Reproductive factors in women with systemic lupus erythematosus: data from the Mexican lupus registry

Abstract

Introduction

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with heterogeneous clinical manifestations. It predominantly affects women, with 9 out of 10 patients being female, and is diagnosed during their reproductive years. This suggests that female reproductive factors play an important role in the development and progression of the disease.

Objective

To describe reproductive factors in Mexican women with SLE who are participants in the Mexican Lupus Registry (LupusRGMX).

Methodology

The identification of Mexican individuals diagnosed with SLE and data collection were carried out through voluntary participation via LupusRGMX and clinical consultations with collaborating rheumatologists, from May 2021 to the present, using the Research Electronic Data Capture (REDCap) platform. All participants met the American College of Rheumatology criteria for the diagnosis of SLE. This is a cross-sectional analysis nested within a cohort. Women over 18 years of age who completed the Reproductive Factors Questionnaire between June 2023 and June 2025 were included. Demographic and clinical variables were analyzed.

Results

A total of 184 women were included, with a median age of 38.5 years (IQR 25%-75%, 18-66). More than 50% of the participants were covered by the Mexican Social Security Institute (IMSS). The majority of patients resided in Querétaro, the State of Mexico, and Mexico City. One-fifth of the patients reported a family history of systemic lupus erythematosus (SLE) (20.6%). The time between the onset of symptoms and diagnosis was reported as less than 6 months by 24% of the patients; however, 27% reported more than 5 years. Of the clinical manifestations, 17.4% reported lupus nephritis. The most common treatment for SLE was antimalarials in more than 70% of the patients and glucocorticoids in almost 60%. The most frequent comorbidities were thyroid disease and hypertension in >10% of patients. The median age at menarche was 12 (IQR 11-13). 64.7% reported a regular menstrual cycle, while 33% reported no menstruation in the last 12 months. Only 8.7% of patients reported contraceptive use at the time of the survey, but 39% reported previous use (Table 1). 86 (46.7%) patients reported having been pregnant; 58 (31.5%) had two or more pregnancies, for a total of 182 pregnancies. Of these pregnancies, 45 (25%) ended in miscarriage and 12.5% ​​were preterm. Fifteen (17.4%) of the women who reported pregnancies experienced complications; the most frequent complication was preeclampsia (in 11 pregnancies). Of the patients who reported breastfeeding, 70% practiced exclusive breastfeeding.

Conclusions

In our population of patients with SLE, one-third reported the absence of menstruation for one year, almost half reported having been pregnant, and one-quarter of the pregnancies resulted in miscarriage. Exclusive breastfeeding was the most common method used among the patients.