Can you tell me about different sub-specalties of obgyn?

The subspecialties. Critical care medicine, female pelvic medicine and     reconstructive surgery urinary incontinence & prolapse of the pelvic organs, gynecologic oncology cancers of the reproductive organs, hospice and palliative medicine, maternal and fetal medicine management of high-risk pregnancies, reproductive endocrinology/infertility biological causes and interventional treatment of infertility.
Ok. Mfm or perinatlogist- high risk ob. Fertility- infertility. Gyn-onc cancer. Ob hospitalist - just deliveries not a board specialty. Urogyn or female pelvic medicine and reconstructive surgery- newest specialty with certification process just started.
There are four. Gynecologic oncology - manage and treat all female cancers, have extensive and broad surgical training. Maternal-fetal medicine - pregnancies only, emphasis on high risk female pelvic medicine and reproductive surgery - also called urogynecology, dealing with bladder function problems and loss of pelvic supports reproductive endocrinology and infertility - run the "in vitro" programs.