An OB/GYN is a doctor who specializes in women’s reproductive health, pregnancy, and childbirth. The name combines two overlapping fields: obstetrics (pregnancy and delivery) and gynecology (the broader care of the female reproductive system). Most physicians in this specialty practice both, though some focus more heavily on one side. There are roughly 20,000 OB/GYNs actively practicing in the United States.
Obstetrics vs. Gynecology
The two halves of the specialty cover different stages of a woman’s life, but they share enough anatomy and surgical skill that they’ve been trained together for over a century.
Obstetrics is the pregnancy side. An obstetrician manages prenatal care, monitors the health of both the mother and the developing baby, handles complications like preeclampsia or gestational diabetes, performs cesarean deliveries, and guides patients through labor and postpartum recovery. Routine prenatal visits typically follow a set schedule: once a month through week 28, twice a month from weeks 28 to 36, then weekly until birth.
Gynecology covers everything else related to the female reproductive system, from a teenager’s first visit through menopause and beyond. That includes menstrual problems, contraception, sexually transmitted infections, pelvic pain, cancer screenings, and hormone-related conditions. Gynecologists also perform surgeries ranging from minor outpatient procedures to major operations like hysterectomies.
What an OB/GYN Actually Treats
The range is wider than many people expect. Common conditions include endometriosis (tissue that normally lines the uterus growing in other areas, causing pain, heavy periods, and sometimes infertility), uterine fibroids (noncancerous growths that can cause heavy bleeding and pelvic pressure), and polycystic ovary syndrome, or PCOS. PCOS occurs when the ovaries or adrenal glands produce higher-than-normal levels of male hormones, leading to irregular periods, acne, thinning hair, excess body hair, and an increased risk of diabetes and heart disease.
OB/GYNs also manage urinary incontinence, pelvic organ prolapse, abnormal Pap smear results, sexual health concerns, menopause symptoms, and early-stage reproductive cancers. They provide the full spectrum of contraception options and counsel patients on family planning.
Surgical Procedures
OB/GYNs are trained surgeons. The most common major surgery they perform is a hysterectomy, the removal of the uterus. At least 430,000 hysterectomies are performed each year in the U.S., making it the second most common surgery among women. More than 80% are done for noncancerous conditions like fibroids, abnormal bleeding, endometriosis, or pelvic organ prolapse.
The field has shifted dramatically toward minimally invasive techniques. By 2012, over 93% of hysterectomies were performed using laparoscopic or vaginal approaches rather than large abdominal incisions. These methods generally mean smaller scars, less pain, and faster recovery. Beyond hysterectomies, OB/GYNs routinely perform cesarean deliveries, removal of ovarian cysts, tubal ligations, and procedures to treat abnormal cervical cells.
Can an OB/GYN Be Your Primary Doctor?
For many women, yes. The American Board of Obstetrics and Gynecology defines OB/GYNs as providers of both primary and preventive care for women, not just reproductive specialists. In practice, this means your OB/GYN can order routine bloodwork, screen for conditions like diabetes or high cholesterol, manage common acute illnesses, address mental health concerns, and refer you to other specialists when needed.
Many health insurance plans recognize OB/GYNs as eligible primary care physicians. Whether this arrangement works well depends on your health needs. If you have complex chronic conditions unrelated to reproductive health, you may benefit from also having an internist or family medicine doctor. But for generally healthy women, an OB/GYN can handle the majority of day-to-day medical care.
Training and Certification
Becoming an OB/GYN requires four years of medical school followed by a four-year (48-month) residency program specifically in obstetrics and gynecology. During residency, physicians train in prenatal care, labor and delivery, surgical techniques, contraception management, and the full range of gynecologic conditions. That’s a minimum of eight years of training after completing a bachelor’s degree.
After residency, OB/GYNs pursue board certification through the American Board of Obstetrics and Gynecology, which involves passing both a qualifying exam and a certifying exam. Certification isn’t a one-time achievement. Doctors must complete ongoing requirements every six years, including reading and answering questions on current medical literature, completing practice improvement activities, and either passing a recertification exam or qualifying through a performance-based pathway.
OB/GYN Subspecialties
Some OB/GYNs pursue additional fellowship training (typically two to three more years) to specialize further. The main subspecialties are:
- Maternal-fetal medicine: focuses on high-risk pregnancies, including conditions like preterm labor, multiple gestations, and fetal abnormalities. These doctors use advanced ultrasound and fetal monitoring techniques.
- Reproductive endocrinology and infertility: treats hormonal disorders and infertility using approaches like IVF and specialized surgery.
- Gynecologic oncology: manages cancers of the reproductive system through surgery, chemotherapy, and palliative care.
- Female pelvic medicine and reconstructive surgery: treats pelvic floor disorders like urinary incontinence and organ prolapse.
- Complex family planning: provides abortion and contraception care for patients with complicated medical histories.
Your general OB/GYN will refer you to one of these subspecialists if your situation calls for more targeted expertise.
When to Start Seeing an OB/GYN
The American College of Obstetricians and Gynecologists recommends that the first reproductive health visit happen between ages 13 and 15. This initial appointment is primarily educational and preventive. It typically does not include a pelvic exam. The goal is to establish a relationship with a provider, discuss menstrual health, and provide age-appropriate guidance on topics like puberty, hygiene, and vaccinations. Routine cervical cancer screening with a Pap smear generally doesn’t begin until age 21.