Egg retrieval is a procedure in fertility treatments, used in in vitro fertilization (IVF) or for egg freezing. This process involves collecting mature eggs from the ovaries after hormonal stimulation. Individuals undergoing this procedure often have questions about their body’s response afterward, especially regarding the return of their menstrual period. Understanding the typical timeline helps manage expectations during recovery.
When to Expect Your Period and the Hormonal Basis
Most individuals can expect their first period within 7 to 14 days following egg retrieval if no embryo transfer occurs or if an embryo transfer does not result in pregnancy. Some may experience menstruation as early as three to five days post-retrieval, while for others, it might take up to four weeks. This initial period signals the body resetting after hormonal stimulation.
Menstruation after egg retrieval results from significant hormonal shifts. During ovarian stimulation, high levels of hormones, particularly estrogen and progesterone, are administered to encourage egg development and thicken the uterine lining for potential pregnancy.
After egg retrieval, these hormone levels drop suddenly. This withdrawal of hormonal support causes the thickened uterine lining, prepared for pregnancy, to shed. The body needs time to restart natural hormone production and for ovaries to recover from stimulation. This shedding constitutes the menstrual period.
Factors That Influence Period Timing
Several elements influence menstruation timing after egg retrieval, leading to individual variations. The specific fertility protocol used, such as agonist versus antagonist protocols, significantly impacts how the body’s hormones readjust. Different medications can affect the menstrual cycle, potentially delaying or accelerating menstruation.
A fresh embryo transfer can also impact period timing. If a fresh embryo transfer is performed, continued progesterone support medication can delay the period even if pregnancy does not occur. Without a fresh transfer, the period arrives sooner as there is no ongoing hormonal support.
Individual hormonal responses and the number of follicles retrieved contribute to variations in period timing. Stress related to the procedure and IVF process can also influence menstrual cycle timing. Ovarian Hyperstimulation Syndrome (OHSS), a side effect of fertility medication, can delay the period.
What to Expect During This Period
The first period after egg retrieval may differ from a typical menstrual cycle. It can be heavier or lighter than usual, and its duration might vary. This altered flow is often due to significant hormonal shifts and the uterine lining building up more than usual during stimulation, leading to more tissue to shed.
Increased cramping is common during this first period, as ovaries may remain enlarged and sensitive following the procedure. Some women report their period starting and stopping, or that flow heaviness varies more than usual. These differences are temporary as the body adjusts.
When to Contact Your Clinic
While many changes after egg retrieval are expected, know when to contact your fertility clinic or doctor. Seek medical attention if your period is significantly delayed beyond the expected window, especially if it does not arrive within two to three weeks.
Contact your clinic if you experience:
- Extremely heavy bleeding, such as soaking through more than one pad or tampon in an hour for several consecutive hours.
- Severe or worsening abdominal pain not relieved by over-the-counter medication.
- A fever higher than 100.4°F (38°C).
- Any signs of infection.
- Rapid weight gain, specifically over two to three pounds in 24 hours.
- Difficulty breathing.