HSG Test (Hysterosalpingography) — What Is It, Procedure & What Results Mean

An HSG (hysterosalpingography) test is an X-ray procedure that checks if the fallopian tubes are open and the uterine cavity is normal. Contrast dye is injected through the cervix via a thin catheter; X-ray images show whether the dye flows freely through both tubes (patent = open) or is stopped (blocked). It is performed on Day 5–10 of the menstrual cycle, takes 15–20 minutes, and is the standard first-line investigation for tubal factor infertility.

The HSG test causes moderate cramping — most women describe it as similar to strong menstrual cramps — during and for a few minutes after the dye injection. The level of discomfort varies by cervical anatomy and individual pain sensitivity. Taking ibuprofen 400–600mg one hour before the procedure significantly reduces cramping. Some centres apply local anaesthetic to the cervix. Most women are comfortable enough to drive home afterwards, though rest is recommended for the day.

A normal HSG report states: "Uterine cavity is of normal shape and size. Both fallopian tubes are opacified with free bilateral peritoneal spillage of contrast." This means the uterus is triangular with no filling defects (no polyps, fibroids, or adhesions), and both tubes are open — dye flowed through and spilled into the abdominal cavity. Any deviation — one-sided spill, no spill, filling defects, irregular cavity shape — requires further investigation or specialist review.

One blocked tube (unilateral): natural conception is still possible through the open tube; IUI is viable. Fertility may be moderately reduced. Two blocked tubes (bilateral): natural conception and IUI are not possible; IVF is the only option. If the blockage is at the fimbrial end with fluid (hydrosalpinx), the tube must be removed surgically (salpingectomy) before IVF — the toxic fluid reduces IVF implantation rate by 50%. Important caveat: proximal (cornual) blockage on HSG is a false positive in 15–30% of cases (tubal spasm) — always confirm with laparoscopy before concluding permanent blockage.

Before IUI: yes — HSG is mandatory to confirm at least one tube is open, as IUI relies on sperm reaching the egg via the tube. Performing IUI without first checking tubal patency wastes cycles and money if both tubes are blocked. Before IVF: technically IVF bypasses the tubes, so tubal patency is not required for IVF success. However, HSG (or pelvic USS) is still performed to identify hydrosalpinx — which must be treated before IVF — and to assess the uterine cavity for polyps or fibroids that reduce implantation rates.