Surgery: What are the advantages and disadvantages of having hormone therapy too?

Photo of a couple talking with a doctor (PantherMedia / Cathy Yeulet)

There is no proof that taking hormone medication before or after endometriosis surgery improves the outcome of the treatment. But hormone products such as GnRH analogues often have side effects and reduce fertility during treatment.

Endometriosis develops when the kind of tissue that lines the womb (endometrium) starts to grow elsewhere in the abdomen. If these areas of endometrial tissue ("endometrial implants") cause severe pain or affect fertility, some women choose to have surgery.

Surgery aims to remove as many visible endometrial implants as possible. Some doctors hope to increase the chances of successful treatment by combining surgery and hormone treatment. In this approach, women take hormone medication before and/or after surgery. The hormone treatment aims to make surgery easier and reduce the likelihood of symptoms coming back after surgery.

Several drugs can be used for this purpose. They suppress hormone production in the ovaries. One option is known as GnRH analogues (gonadotropin-releasing hormones). These medications have a number of side effects such as increased hair growth, hot flashes and osteoporosis.

An alternative to GnRH analogues are hormonal contraceptives like the pill. They usually contain progestins and estrogens, and are generally better tolerated than GnRH analogues. Women are very unlikely to become pregnant during hormone therapy.

Research on hormone therapy before or after surgery

Researchers at the Cochrane Collaboration, an international research network, looked into the advantages and disadvantages of hormone therapy in addition to surgery. They evaluated 16 studies in which medication was used either

  • only before or only after surgery, or
  • both before and after surgery.

About 1,400 women took part in the studies. Most of them used GnRH analogues. So not much is known about the effects of using other hormonal contraceptives like the pill before and/or after surgery.

Research on hormone therapy before surgery

Two studies compared the outcomes of surgery following hormone therapy with the outcomes of surgery alone. There was some evidence that hormone therapy before surgery could reduce the size of endometrial cysts. But the studies didn't look into whether this also reduced the pain or whether the women had other benefits, for instance regarding fertility.

Research on hormone therapy after surgery

Twelve studies looked into the effect of hormone therapy after surgery. They produced conflicting results: In one study hormone therapy reduced pain after surgery, but that was not the case in other studies. Taking hormones after surgery wasn't found to improve fertility. The studies didn't provide any evidence that hormone therapy after surgery reduced the likelihood of endometriosis coming back either.

Research on hormone therapy both before and after surgery

Only one study with a small number of women looked into whether taking hormones both before and after surgery helps. The study didn't provide enough reliable data to be able to draw any clear conclusions about the advantages and disadvantages of this treatment approach.

Side effects

Many participants who had hormone therapy reported side effects. However, most studies didn't record the side effects accurately enough to be able to say how common they were. Many women who had hormone therapy reported that they didn't have their period during the treatment, so they weren't able to get pregnant. That is a major disadvantage for women who are trying to get pregnant.