If you’re starting to explore fertility treatment or even just researching your options, you might have come across the acronym REI. But what exactly is an REI, and how are they different from your regular OB/GYN? Let’s clear that up!

What is an REI?

REI stands for Reproductive Endocrinologist and Infertility Specialist. These are medical doctors who’ve gone beyond the usual OB/GYN training to focus specifically on fertility and hormone-related issues. They’ve completed extra years of specialized training (called a fellowship) to help people who are struggling to conceive or dealing with complex reproductive health challenges.

REI vs. OB/GYN: What’s the difference?

OB/GYN:

Focus: General reproductive health, eg. pap smears, pregnancy care, birth control

Training: Medical degree + OB-GYN residency

Best for: Routine women’s health and pregnancy care

REI:

Focus: Fertility treatments, hormonal issues, IVF, PCOS, egg freezing

Training: Medical degree + OB/GYN residency + REI fellowship (specialized fertility training)

Best for: Diagnosing and treating infertility and complex hormonal conditions

When should you see an REI?

• You’ve been trying to conceive (TTC) for 6–12 months without success (or sooner if you’re over 35).
  
  
• You’re thinking about freezing your eggs and want expert advice on timing and options.
  
  
• You have a known fertility condition, like PCOS, endometriosis, or low ovarian reserve (AMH), and want specialized care.
  

Why it matters

Your OB/GYN is amazing for general reproductive care, but if you’re facing fertility challenges or need advanced treatment like IVF, an REI is the expert to guide you through that journey with personalized support and the latest medical options.

Need help navigating your next step? Whether you're just starting to explore your fertility options or ready to see an REI, Gaia's here to support you with expert guidance, flexible financing, and real human care — from day one to day baby. Learn how Gaia can help.

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