2023 OB/GYN Clerkship Guide


The OB/GYN clerkship is a hybrid core rotation, which means it provides an excellent learning experience for both students interested in pursuing the specialty as well as those who are not. OB/GYN has elements of both clinical medicine and surgery, so students hoping to become either surgeons or clinicians can hone their skills with this rotation.

“If I have a monument in this world, it is my son.” – Maya Angelou

This guide will cover the OB/GYN clerkship, including when to place this rotation, how to make the most of your rotation, OB/GYN clerkship resources, the shelf exam, and the pros and cons of pursuing this specialty.


Intro to the OB/GYN Clerkship

Clinical clerkships, also referred to as clinical rotations, give medical students the chance to practice medicine while being supervised by a practicing or otherwise established doctor. Clerkships provide students with first-hand knowledge of what the various medical specialties are really like. This way, students can better determine the field of medicine they feel most passionate about and want to practice in their future career as a physician.

Most US medical schools require the following rotations:

Medical School Clerkship icons

Some schools may also require additional rotations, such as emergency medicine, radiology, anesthesiology, and more.

OB/GYN consists of two components: obstetrics and gynecology. Obstetrics is the medical and surgical management of pregnancy, whereas gynecology is the medical and surgical management of the female reproductive tract.

Buckle up for a noisy and hectic adventure during this core rotation. OB/GYN is the specialty concerned with the female reproductive tract, as well as the delivery of babies. The second component of the specialty makes the rotation unpredictable, as births do not follow a straightforward 9-5 schedule.

On the other hand, OB/GYN is one of the most joyous rotations you will encounter. There is no other specialty where a new life is born right in front of your eyes. The pervasive death all healthcare personnel deals with (spontaneous abortions and tumoral conditions) is balanced in OB/GYN with births.


When to Place the OB/GYN Rotation

The best time to place this rotation is after your surgery rotation. OB/GYN is a hybrid rotation, requiring a solid framework of both knowledge and technical skills, as well as the ability to suture. Alternatively, if you want to pursue surgery as a specialty, you might choose to place OB/GYN before surgery, allowing you to come in with a stronger OR foundation.

Another factor to consider is whether or not you want to pursue it as a specialty. If you are interested in pursuing OB/GYN as a specialty, it’s best to place it second or third out of the total of four quarters of the year.

This way, you will have acquired a foundation of experience from your surgery clerkship and perhaps your internal medicine clerkship before entering the rotation you feel the most enthusiastic and passionate about. Placing it first, when you’re just getting used to your third year clerkships, means you’re less likely to impress your seniors and attendings. By not placing it last, you’re better able to collect the number of references you need to apply to away rotations and residency programs.

Keep in mind that you may not have the opportunity to choose your clerkship order, depending on your school’s rotation process.


Making the Most of the OB/GYN Rotation


Structurally, the rotation will have an obstetrics component and a gynecology component. Obstetrics will consist of deliveries, assisting in the operating room for C-sections, and working in the outpatient clinic. Gynecology will require you to mostly work in the clinic and the OR. Common surgeries will be hysterectomies (both open and laparoscopic) or biopsies.

The OB/GYN rotation will place students in both the delivery room and the outpatient clinic. The outpatient clinic is meant for pregnancy follow-ups and consults. To impress your attendings, study up on the most common pathologies before the outpatient clinic.

Such topics include common screening guidelines during pregnancy, such as performing an oral glucose tolerance test at 24-28 weeks gestation, criteria and risk factors for pregnancy complications, (for example, a previous C-section is a risk factor for placenta previa), and perinatal period treatments, such as erythromycin for conjunctivitis prophylaxis. You will need surgical skills for both the gynecology and the obstetrics OR.

The other structural difference of the rotation is in the consults. Gynecologic consultations will focus on reproductive tract pathology and screening. Keep in mind the USPSTF recommendations for breast and cervical cancer.

The obstetrics consultations are at the other end of the spectrum. For these consults, you will need to pay close attention and think on your feet, as decisions regarding urgent conditions, such as abnormal uterine bleeding and preeclampsia, will be made.


Having a good understanding of the following conditions will help you impress your attendings as well as help you provide insight into your patients.

Gynecologic cases:

  • Ovarian Tumors
    • Alongside breast tumors, ovarian tumors are a frequent pathology encountered in people above 60 years of age. They can be:
  • Germ cell tumors
    • Mature teratomas: on ultrasound (U/S), they appear as echogenic masses with a posterior shadow (sebaceous glands or hair follicles). They are more frequently found in young women.
    • Dysgerminomas: suspect in an ovarian mass with high LDH or hCG.
    • Yolk sac tumor: once again seen in young women with notably elevated AFP.
  • Epithelial tumors: more common in older patients.
    • Serous carcinoma and cystadenocarcinoma: U/S will reveal a cystic/solid mass with thick septae and papillary projections.
  • Sex-cord stromal tumors
    • Fibroma: associated with Meigs syndrome (ascites, pleural effusion, and ovarian mass).
    • Sertoli-Leydig tumor: screen with serum testosterone levels.
    • Granulosa cell tumor: the most common sex-cord stromal tumor. It is associated with a high inhibin level.
  • Abnormal uterine bleeding (AUB): Approach to the Ddx includes discriminating between structural and functional causes. When screening for these etiologies, bear in mind the mnemonic:
    • PALM (structural): PCOS, adenomyosis, leiomyoma, malignancy.
    • COEIN (functional): coagulopathy, ovulatory dysfunction, endometrial, iatrogenic, not classified.
  • STDs
    • Screening for STDs is recommended for patients who are 18-24 years old. This consists of NAAT on a vaginal swab. The two main causes of STDs are C. trachomatis and N. gonorrhoeae. Since co-infection is frequent, when treating one, medication is also prescribed for the other infection. The treatment consists of ceftriaxone for N. gonorrhoeae. For C. trachomatis, the treatment consists of a 7 day course of doxycycline.
    • If the patient is a high risk patient, consider screening for other STDs, such as: syphilis, HIV, HBV, HCV, or HSV. For syphilis, dark-field microscopy is required for primary syphilis, while VDRL followed by FTA-ABS is recommended in cases of secondary syphilis. HBV, HCV, and HSV require serology testing. HIV screening is done through an ELISA and confirmed with a Western-Blot.

Obstetrics consults:

  • Premature rupture of membranes (PROM): One common complication during these consults is the premature rupture of membranes. PROM is diagnosed with:
    • Best initial test consists of a nitrazine paper test.
    • Other diagnostic tests are the Fern test or transabdominal instillation of indigo carmine.
    • U/S is indicated to evaluate amniotic fluid volume.
      • The treatment for a term PROM is labor induction. If the patient is less than 32 weeks gestation, then expectant management with bed rest is recommended.
  • Fetal heart rate tracings
    • Variable decelerations
      • Pathophysiology: There are two types of variable decelerations. 1) Intermittent variable decelerations. In a span of 20 minutes, less than 50% of the uterine contractions exhibit variable decelerations. 2) Recurrent variable decelerations. In a span of 20 minutes, more than 50% of the uterine contractions are followed by variable decelerations.
      • The compression or prolapse of the umbilical cord is responsible for intermittent perfusion through the umbilical vein.
      • Traits: The nadir is abrupt (<30 seconds to obtain it). There is a variable temporal relationship with the uterine contractions. The decelerations last between 15 seconds to 2 minutes.
      • Treatment: It depends on the type of variable decelerations. Intermittent variable decelerations mean no treatment is required. Recurrent variable decelerations mean you must treat with intrauterine resuscitation; if it fails, then proceed with an emergency cesarean delivery.
    • Early decelerations
      • Pathophysiology: They occur as the fetal head is compressed by uterine contractions, causing a vagal response.
      • Traits: The nadir (= peak/minimum of the fetal heart deceleration) is gradual, occurring at least 30 seconds after the beginning of the uterine contraction. Its lowest point and end corresponds to the peak and end of the uterine contraction, respectively.
      • Treatment: Proceed with vaginal delivery, as there is no fetal distress.
    • Accelerations (Healthy)
      • Physiology: Transient increases in the fetal heart rate associated with fetal movements, uterine contractions, and other stimulatory processes.
      • Traits: Rise in fetal heart rate of at least 15 BPM for at least 15 seconds. Two or more accelerations in 20 minutes constitutes a reactive non-stress test (NST) in the setting of a normal fetal heart rate (110-160 BPM) and moderate variability (6-25 BPM)
      • Treatment: None necessary
    • Late decelerations
      • Pathophysiology: Late decelerations are caused by uteroplacental insufficiency. This leads to fetal hypoxia and acidosis. Such findings are a risk factor for cerebral palsy or hypoxemic/ischemic encephalopathy.
      • Traits: Like early decelerations, the nadir is gradual (≥ 30 seconds). The deceleration begins after the initial uterine contraction took place.
      • Treatment: Intrauterine resuscitation—amnioinfusion, maternal repositioning. If the above fails, opt for an emergency cesarean delivery.
    • To remember the above tracings and their causes, use the VEAL CHOP mnemonic:
      • Variable
        • Cord compression
      • Early
        • Head compression
      • Accel
        • OK
      • Late
        • Placental insufficiency
    • Prolonged decelerations
      • Pathophysiology: They are caused by prolonged uterine contractions, IVC syndrome, a rapid decrease in mother’s blood volume (bleeding/trauma), or peridural anesthesia. They cause fetal hypoxia and acidosis.
      • Traits: Decrease in FHR that lasts from 2 to 10 minutes.
      • Treatment: Intrauterine resuscitation; cesarean delivery if it fails.
  • Stages of labor
  1. First stage
    • Latent phase: cervix dilation from 0 to 6 cm (typically at a rate of ~1 cm/hr). It may be prolonged due to inappropriate anesthesia, which, while providing pain relief, can slow down the process as a whole.
      • A normal latent phase of labor lasts from 14 (multiparous) to 20 (nulliparous) hours
    • Active phase: cervix dilation from 6 to 10 cm (typically at a rate of 1-4 cm/hr). It can be prolonged due to cephalopelvic disproportion (i.e., macrosomia).
      • A normal active phase of labor lasts 2-3 (multiparous) up to 4-6 (nulliparous) hours. Increases in the rate of cervical dilation range from 1.2 cm/hr (nulliparous) to 1.5 cm/hr (multiparous).
  2. Second stage
    • Complete cervical dilation (10 cm) to delivery.
      • A normal second stage lasts as short as <1 hour (multiparous) to <2 hours (nulliparous). Receiving an epidural lengthens these times by ~1 hour.
  3. Third stage
    • It consists of the delivery of the neonate and of the placenta. It requires uterine contraction and placental delivery to achieve hemostasis.
      • This stage should only last up to 30 minutes. Otherwise, there is worry for a retained placenta.


They are frequently tested in the obstetrics chapter. Here are some common teratogens that might come up on the shelf.

ACEiRenal dysgenesis, intrauterine growth restriction (IUGR), oligohydramnios
ValproateBroad nasal bridge, neural tube defects, cleft lip/palate
Vitamin A derivatives (isotretinoin)Spontaneous abortion, CV defects, thymic agenesis, cleft lip/palate, microtia, microphthalmia
WarfarinNasal hypoplasia, stippled bone epiphyses, IUGR, developmental delay


Skill acquisition

Both the consultations and the delivery room are amazing places to cultivate your clinical skills.

  • Inside the delivery room, you can hone your surgical skills. Procedures vary from practicing sutures to occasionally using forceps or vacuum to assist the delivery. Review sutures and knot tying before your days in the delivery room. Specifically, review the two handed tie, instrument tie, deep dermals, running subcuticular, and simple interrupted sutures.
  • Other essential skills for the OB/GYN rotation are history taking and the physical exam. The particularities of the history in an OB/GYN environment are:
    • Gravida (number of pregnancies)
    • Para (number of live deliveries)
      • You may also need to be more descriptive by providing GTPAL
        • Gravida – number of pregnancies
        • Term births
        • Preterm births
        • Abortions
        • Living children
      • For example, G1T1P0A0L1 describes someone with one living child from a term pregnancy
    • Family history of gynaecologic/obstetrics conditions
    • Type of previous deliveries (Cesarean vs. vaginal)
    • Previous hypertension and/or diabetes
    • History of sexual transmited diseases
    • History of ToRCHEs infections (e.g., a transplanted patient who developed pneumonia may have CMV pneumonitis)
  • Depending on the clinical environment, the physical exam will include:
    • A thorough external inspection.
    • Speculum insertion. For the patient’s comfort, warm and lubricate the speculum before introducing the device at an angle while it is still closed. Once it is in place, use the screw to hold the pieces open during inspection.
    • After inspecting the vaginal vault and cervix, perform a Pap smear (if indicated). When removing the speculum, pay special attention to not pinch the cervix while closing the instrument. Furthermore, do not attempt to remove the speculum while it is still open.
    • Lastly, perform a bimanual inspection using a lubricated, gloved hand to assess the vagina, uterus, Douglas pouch, and the ovaries.
      • Manual inspection may come before the speculum exam depending on the preferences of your preceptor.

Expect to improve your U/S skills in the consultation room. It’s vital you understand the differences between the transvaginal and transabdominal U/S. The transvaginal U/S is superior to the transabdominal U/S in cases like pregnancy evaluation (third trimester), ectopic pregnancies, and endometrial cancer.

If there is a relative contraindication to transvaginal U/S, such as vaginitis, you could opt for a transabdominal U/S.

Keep in mind that the exact nature of your rotation will depend on your specific school. The exposures and settings you will experience will vary, as will the skills and knowledge you need to succeed. How your rotation is designed will also play a role in your schedule, how early you need to come in, whether your pre-round, etc.

For example, you may have 6 weeks of OB/GYN, 3 of which are dedicated to obstetrics (labor and delivery) and 3 with various gynecologic teams. Within your labor and delivery weeks, you may have an entire week dedicated to nights and another to maternal fetal medicine. Your gynecology weeks could be all outpatient visits consisting of health checkups or you may be in the OR with the gynecologic oncology surgeons debulking a massive uterine tumor.

Whatever your upcoming days look like, prepare accordingly by developing a baseline knowledge of the most common cases you encounter and skills you will use.


Useful Apps for the Wards

  • MDCalc: Free app that allows you to calculate various risk/score calculations.
  • UpToDate helps you find the most up-to-date information in medicine.
  • Journal Club allows you to look up summaries of key clinical trials that are relevant for different diseases or conditions so that you can present them on rounds.


OB/GYN Clerkship Resources

There are numerous resources you can use to study OB/GYN content. You can start with an Anki deck, such as AnKing, but for comprehensive resources, choose books like BluePrints OB/GYN and Step-Up to Medicine.

The best question bank resource for Step 2 CK is UWorld. Their section on OB/GYN will prepare you for the bulk of the shelf and Step 2 CK exam. To ace these exams, after finishing a block, review the questions you answered wrong as well as the topics of each question.

To study systematically, research each pathology’s clinical presentation and medical history, followed by the diagnostic criteria and tests. Lastly, add the management of the condition to your summary sheets. If you have more time, begin either uWise or Amboss. uWise is a question bank created by the Association of Professors of Gynecology and Obstetrics, and it’s thought to be better for the shelf exams.

To practice for exam day, we highly recommend the NBME shelf exams. There are four tests, and each asks 50 questions. The session lasts five hours in total. These questions will be similar to both the Step 2 CK exam questions on OB/GYN and the shelf exam.

This curated knowledge base will be extremely helpful during review times, such as before the Step 2 CK exam and before the shelf exam. Placing them in a digital format, such as in Notion, will not only enhance your ability to rapidly review your weak spots, but it also means you’ll be able to quickly find the information you need during your consultations.

Clerkship Tips Rotation acvice graphic


OB/GYN Shelf Exam

The OB/GYN shelf exam’s questions are unique, especially the obstetrics questions, where no amount of previous IM knowledge will help you. The only other time you will face similar questions is on the USMLE.  When preparing for this exam, keep in mind that you are preparing for a high score on Step 2 CK as well, not just the shelf exam itself. The shelf is a way to prepare for Step 2 CK and identify your knowledge gaps.

Start with the OB/GYN section from UWorld. Complement UWorld with a review book, such as BluePrints OB/GYN. The pathologies may still be unclear after your first pass through UWorld, so it’s ideal to use another question bank, such as Amboss, to drive home any sticky points. Lastly, to simulate the exam conditions, a CMS (Clinical Mastery Series) form from NBME will demonstrate how the questions will be phrased on the shelf.

Note that depending on your school, the weight of shelf exams may vary. Your exams could be worth up to 80% of your clerkship grade, whereas other schools may only have a pass/fail process. Adjust the intensity of your studying to the weight of your shelf exams to make the most of your limited time.

Learn more from our How to Prepare for Shelf Exams Guide.


Residency Choices: Pursuing the OB/GYN Specialty

OB/GYN is one of the most accessible specialties. It ranks 14th on our MSI index specialty comparison of 24 specialties. The average annual compensation falls around $300k.

View our comprehensive Specialty Competitiveness Index, which assesses specialties based on USMLE Step 1, Step 2 CK, Top 40 NIH, publications, and more.

Although it has a hectic schedule, there are institutions that offer three or four day weeks. Thus, instead of having to go to the hospital every day, OB/GYN presents the unique advantage of compressing those hours into three or four days.

The place where OB/GYN shines as a specialty is in its subspecialties. After completing your residency, you may further your career with either a gynecology or obstetrics subspecialty. Here are some subspecialties to consider.

  • Gynecologic oncology. While its schedule resembles a 9-5 job, you will be responsible for taking care of patients with severe illnesses. However, it also comes with the thrill of a surgical specialty, as many of the ovarian and cervical cancers have a surgical indication.
  • Reproductive endocrinology and infertility. This subspecialty is a consultation-based subspecialty. It gives you the chance to not only play a role in the conception of the newborn, but also to consider the patient from a social dynamic with the loved one. If long-term care and patient relationships sound good, then this is the right specialty for you.
  • Critical Care Obstetrics. There are two types of students who pursue this subspecialty: those who love physiology, and those who thrive under pressure. The patient population is on the brink of death, so most of the cases are emergencies. Rapid thinking and application of physiology concepts are essential to stabilizing the patient.
  • Female pelvic medicine and reconstructive surgery. These specialists provide care for women who have had injuries related to previous births. For instance, they take care of urinary incontinence, pelvic prolapses, or lacerations related to the birth.
  • Maternal-fetal medicine. This fellowship will help improve your knowledge of the pre-partum care of both the mother and the fetus.
  • Complex family planning medicine. This branch offers the chance to gain experience with pregnancy termination methods, diagnostic methods to confirm uterine and tubal pregnancy, and sterilization.
  • Minimally invasive gynecology surgery. This fellowship allows for further specialization into fibroid surgeries, surgery for endometriosis, and the practice of hysteroscopy.

There’s a lot to love about OB/GYN, including the continuity of care. If you enjoy building long-term relationships with patients, this specialty will have a strong draw—It is truly womb to grave. You will take care of patients for their entire lives, including their best and worst days.

For those who enjoy excitement and adrenaline, there’s also an emergency element involved in being an OB/GYN. You will face enough emergencies to keep you on your toes. Plus, since you have two patients, the mom and the baby, there’s an added degree of uncertainty to further add to the excitement.

Unfortunately, there is  a downside to the lifestyle. While delivering babies is exciting and rewarding, it can be profoundly sad when your patients experience a pregnancy loss or cancer. It’s not all sunshine and newborns. Additionally, it’s often a messy specialty with high blood loss, which is often combined with other bodily fluids and solids during labor. Let’s just say there’s lots of fluids and smells on the job.

Learn more about whether or not the OB/GYN specialty is right for you: ​​So You Want to Be an OB/GYN (video and article).


Final Thoughts on the OB/GYN Clerkship

OB/GYN is one of the hybrid core rotations. It has elements of surgery and elements of clinical medicine. Both future surgeons and future clinicians can enhance their skills during this rotation. For instance, a surgeon may spend more time in the delivery room practicing their sutures, while an internist will increase their breadth of technical skills required for using U/S.

For the shelf and Step 2 CK, your knowledge from previous rotations will not suffice. The obstetrics element will consist of completely new information. To improve your score, start with UWorld on day one. Finally, simulate the exam conditions with a CMS form.

Don’t forget that the OB/GYN rotation is the best time to get a letter of recommendation if you want to pursue this specialty further. Moreover, starting to network at this stage will greatly enhance your future career.

OB/GYN can be an especially rewarding and high stakes specialty, but it comes with a lot of pressure, and a lot of mess. It’s not for the faint of heart, but if you love the idea of building lasting relationships with your patients and bringing new life into the world, OB/GYN is definitely a specialty to consider.


Get the Advice and the Resources You Need

Med School Insiders offers a number of Residency Admissions Consulting Services designed around your specific needs. We can help you prepare for residency with application editing, interview prep, and mock interviews.

View our library of resources, including guides on the entire residency application process, how The Match algorithm works, how to choose a specialty, and more.


Leave a Reply