What is an hCG trigger injection used for?

Human chorionic gonadotropin, or hCG, acts similarly to the natural hormonal signal that occurs before ovulation. After ovarian stimulation has encouraged follicles to develop, the injection helps the leading follicle complete maturation and release an egg. The timing is planned so intercourse, insemination, or egg retrieval can be arranged around the expected ovulation window.

The injection does not create eggs and does not treat every cause of infertility. It is one part of a treatment plan, and the dose and timing depend on your scan findings and prescribed protocol.

Use the injection exactly at the time given by your fertility team; timing can affect the next treatment step. Confirm how it should be stored, prepared, and administered, and ask what to do if a dose is late or missed. Keep a record of the time it was given and attend the planned monitoring appointment.

Mild soreness or redness where the needle entered can occur. Your team may also explain how ovarian stimulation can affect your body and what symptoms to report.

Contact your fertility clinic promptly for increasing abdominal swelling or pain, repeated vomiting, trouble breathing, faintness, or a noticeable reduction in urination after stimulation. These symptoms can signal a treatment-related ovarian problem that needs assessment. Seek urgent medical help for severe pain, collapse, or breathing difficulty.

Ask when ovulation or egg retrieval is expected, which activities or medicines to avoid, how pregnancy testing may be affected by residual hCG, and which symptoms should prompt an urgent call.