If she is just a gestational carrier, the answer is no, she isn't. In gestational surrogacy arrangements, the egg cell is provided by the intended mother as long as possible, or by an egg donor if needed. The goal is to avoid that there's a genetic link between the GC and the baby-to-be in order to prevent the creation of an emotional bond between them.
Conversely, in traditional surrogacy, the surrogate is the biological and birth mother at the same time. This is precisely the reason why this kind of surrogacy is not practically not used today in the USA.
Read the full article on: What Is a Surrogate Mother? – Everything You Should Know ( 89).

Andrea Rodrigo
Bachelor's Degree in Biotechnology from the Polytechnic University of Valencia. Master's Degree in Biotechnology of Human Assisted Reproduction from the University of Valencia along with the Valencian Infertility Institute (IVI). Postgraduate course in Medical Genetics.