# Adherence to vitamin and dietary supplement intake in fertility and pregnancy care: insights into knowledge, information satisfaction, and formulation variability

## TL;DR

This study explores how women in Germany follow vitamin and supplement advice during fertility and pregnancy, finding high adherence but limited knowledge and satisfaction with information.

## Contribution

The study provides new insights into supplement adherence, knowledge gaps, and formulation variability among women in fertility and pregnancy care in Germany.

## Key findings

- Most participants used supplements, primarily starting preconceptionally, with high adherence but low satisfaction with information.
- Supplement formulations varied widely, with folic acid and iodine being the most consistently included nutrients.
- Higher information satisfaction was linked to pregnancy status, younger age, and lower educational level.

## Abstract

This study investigated adherence to vitamin and dietary supplement intake, satisfaction with healthcare-provided information, and knowledge of essential micronutrients among women seeking fertility treatment and pregnant women in Germany.

An anonymous online survey (34 questions) assessed sociodemographics, supplement intake, knowledge and motivations. Adherence and satisfaction were measured by MARS-D (Medication Adherence Rating Scale) and SIMS-D (Satisfaction with Information about Medicines Scale).

Among 254 participants, 93.7% reported supplement use, and 86.6% began intake preconceptionally. On average, participants consumed two (2.0 ± 1.36) supplements concurrently. Most multiple micronutrient supplements (MMS) contained folic acid (100%) and iodine (86.2%) at recommended doses, other nutrients varied considerably. Participants knew two (1.81 ± 1.43) out of six micronutrients prior to information provision, increasing to three (2.94 ± 1.65) afterwards. Satisfaction with information (SIMS-D: 7.46 ± 5.92) was low, whereas adherence was high (MARS-D: 27.16 ± 3.06). Higher information satisfaction was associated with pregnancy (p = 0.007), younger age (p = 0.009), and lower educational level (p = 0.024). Adherence was linked to trimester (p = 0.007) and region (p = 0.013), with higher MARS-D scores in the first trimester and among participants from North Rhine-Westphalia. Key motivations were protecting the child and preventing deficiencies; main barriers included lack of awareness and feeling overwhelmed by preparation oversupply.

Despite high adherence, knowledge and satisfaction with information remain limited. The wide variability in MMS formulations may pose risks of over- or underdosage. Combining personalized consultations with trustworthy media resources is essential to assess individual needs and provide detailed recommendations.

The online version contains supplementary material available at 10.1007/s00404-025-08288-w.