If I recall, midwifery programs in the Philippines are not offered as degree programs. A CNM is a Registered Nurse with a graduate degree (master's or higher) focused on the advanced practice of nurse-midwifery. California will certify Nurse-Midwives via three routes as follows: (1) must have attended a CA approved nurse-midwifery program, (2) must have attended a nurse-midwifery program that conforms to CA's educational standards, or (3) must be certified as a nurse-midwife by a US state or by the national organization that certifies CNM's.
However, it is important to also distinguish that not all midwives are nurse-midwives and both those terms are not interchangeable. The CM credential is awarded to those who are trained in midwifery programs that are not affiliated with nursing or advanced practice nursing (also called direct-entry midwives because they didn't start out as nurses). The American Midwifery Certification Board awards both CNM and CM credentials as a way to acquire national certification. It sounds like this board has no mechanism for foreign-trained midwives to be certified as you can find here
Incidentally, California also awards a "Licensed Midwife" title. In California, CNM's are regulated by the Board of Registered Nursing while LM's are regulated by the Medical Board. There is a list of CA schools with approved LM training programs found here
. It sounds like there is also no mechanism for foreign-trained midwives to challenge the LM title in California either as you can see here
In short, I don't see how a Philippine-trained midwife would qualify under any of the above routes.