Follicular study usually requires multiple transvaginal ultrasound sittings—commonly 2–4, sometimes up to 5. A baseline scan on cycle day 2–3 is followed by repeat scans every 2–3 days starting around day 8–10 to track follicle growth, with a final pre‑ovulation scan to time ovulation or insemination. Exact number depends on cycle length, treatment response, and clinical needs.

A single follicular scan is a one-time transvaginal ultrasound done to measure the size and number of ovarian follicles and assess the uterine lining. It evaluates follicle growth to predict ovulation timing, helping time intercourse, intrauterine insemination, or trigger injections during fertility treatment. It’s usually performed mid-cycle and provides objective information on follicle maturation and endometrial thickness.

Follicular study (transvaginal ultrasound) costs vary by country and facility: in India about ₹800–3,000 per scan in private clinics; in the US typically $200–1,000 per scan (higher at some hospitals). Under the NHS it’s covered when clinically indicated. Multiple scans are common during a cycle, so total monitoring costs equal the per-scan fee times number of visits.

The best time for a follicular study is in the early follicular phase—ideally a baseline transvaginal scan on cycle day 2–3. Serial scans are then done every 2–3 days starting around day 8–10 to monitor follicle growth and endometrial thickness, continuing until a pre-ovulatory follicle is reached. Timing may be adjusted for irregular cycles per your clinician.

Typically one. Each ovarian follicle normally contains a single oocyte (egg); at ovulation a mature follicle releases that one egg. Primordial follicles present from birth each hold one oocyte. Rarely, a follicle may contain two oocytes, which can lead to fraternal twins if both are fertilized, but that is uncommon. This one‑egg rule underlies typical ovulation and fertility.

A dominant follicle about 18–24 mm in diameter is generally considered mature and most likely to release an egg suitable for fertilization. Ovulation usually follows the LH surge within 24–36 hours when the follicle reaches this size. Follicles under ~16 mm are often immature; larger follicles may still ovulate but their timing and quality should be evaluated by a fertility clinician.