There have been no studies (that we know of) on this.
GnRHa treatments (aka chemical menopause) suppress ovulation and stop any hormone fluctuation from occurring.
If the patient then needs or opts to continue to ovary removal, once the ovaries are removed, you will immediately enter surgical menopause, and your hormone levels will drop significantly (this can take weeks to months).
It is important to note that surgery is a major disruption to your body, not just the physical element of going through surgery and anesthesia but also your hormone levels. There is no guarantee how anyone will feel after the surgery, and for those with hormone sensitivities, this transition period can potentially be difficult, so it is important to ensure you have support in place and speak with your provider.
Many patients are already on HRT before surgery, which can potentially ease the transition into surgical menopause. Do note that starting HRT can also be a difficult process for some in the first few weeks, but this often settles in 4-6 weeks.
In theory, it would make sense that if your ovarian hormones are already very low, the shock of entering surgical menopause would be lessened. However, this is an area that has yet to be studied, and so all cases must be treated on an individual basis.
Added May 2023.
Jordan C. Barone
IAPMD CAB Affiliate
MD/Ph.D. Candidate (Medical Scientist Training Program)