First-Birth Outcomes by Endometriosis Type

Endometriosis Subtype May Influence Fertility Outcomes After Surgical Diagnosis

Key Points

Highlights: 

• More than half of women with surgically diagnosed endometriosis achieved a first birth after diagnosis.
• Peritoneal endometriosis was associated with the most favorable first-birth outcomes among endometriosis subtypes

Importance: 

• Fertility prognosis after endometriosis surgery appears to differ according to disease subtype, emphasizing the importance of phenotype-specific counseling and reproductive planning.

What’s done here:

• This is a retrospective population-based cohort study of 9,590 nulliparous women aged 15–49 years with surgically verified endometriosis identified through Finnish national registers.
• First-birth rates were evaluated according to endometriosis subtype, including peritoneal (n=3,146), ovarian (n=3,020), deep (n=659), and combined/other forms (n=2,765). 

Key results:

• More than half of women achieved a first birth after surgical diagnosis of endometriosis.
• Peritoneal endometriosis was associated with the most favorable first-birth outcomes among all disease subtypes.
• Women with peritoneal endometriosis had the shortest time to first birth after diagnosis.
• Prior infertility did not preclude successful reproductive outcomes, with this subgroup demonstrating the highest first-birth incidence rates.
• Ovarian endometriosis was associated with older age at diagnosis.

Strengths and Limitations:

• Strengths are the large nationwide cohort, long-term follow-up, and subtype-specific analysis of surgically verified endometriosis in a real-world population.
• Limitations are the inability to determine pregnancy intention, lack of detailed information regarding fertility treatments after surgery, and restriction to surgically diagnosed disease, which may limit generalizability. 

From the Editor-in-Chief – EndoNews

"Endometriosis is often discussed as a single disease entity, yet its clinical manifestations and reproductive consequences can vary substantially across disease subtypes. This study is noteworthy because it moves beyond the traditional question of whether endometriosis affects fertility and instead examines how reproductive outcomes differ according to disease phenotype. The findings suggest that women with peritoneal endometriosis experience more favorable first-birth outcomes than those with ovarian or more complex disease presentations.

Equally important is the observation that a previous diagnosis of infertility did not preclude successful reproductive outcomes. A substantial proportion of women with infertility subsequently achieved a first birth, underscoring the heterogeneity of fertility trajectories among women with endometriosis. These findings highlight the importance of avoiding overly generalized assumptions when counseling patients regarding future reproductive potential.

Although registry-based studies cannot fully account for pregnancy intentions, fertility treatments, or other factors influencing reproductive decisions, they provide valuable population-level insights that are difficult to obtain in smaller clinical cohorts. Taken together, these results support a more phenotype-specific approach to reproductive counseling and emphasize that endometriosis subtype may represent an important consideration when discussing fertility expectations after diagnosis and treatment."

Lay Summary

Women with peritoneal endometriosis demonstrated the most favorable first-birth outcomes following surgical diagnosis, according to a new study published in Fertility and Sterility. The findings also suggest that women with a prior infertility diagnosis can achieve substantial reproductive success after endometriosis surgery.

“The overall chance of first birth in women with surgically verified endometriosis seems good,” the authors concluded. “The findings emphasize the impact of age, timely diagnosis of endometriosis, and infertility treatment.”

To evaluate first-birth rates according to endometriosis subtype, Dr. Oskari Heikinheimo and colleagues from the Department of Obstetrics and Gynecology, Helsinki University Hospital and the University of Helsinki, Finland, conducted a retrospective population-based cohort study using Finnish national registry data.

The study included 9,590 women aged 15–49 years with surgically verified endometriosis who had not previously given birth. Of these, 3,145 had peritoneal endometriosis, 3,020 ovarian endometriosis, 650 deep infiltrating endometriosis, and 2,765 combined, rare, or unspecified disease subtypes.

Overall, 54.1% of women achieved a first birth following surgical diagnosis of endometriosis. Women with ovarian endometriosis were older at diagnosis than women with other disease subtypes, with a median age of 32.5 years.

The overall first-birth incidence rate was 7.67 per 100 person-years. Women with peritoneal endometriosis demonstrated the highest incidence rate (9.44 per 100 person-years) among all disease subtypes.

Prior infertility was documented in 45.6% of women before surgery. Among these women, 65.9% subsequently achieved a first birth, corresponding to an incidence rate of 11.5 per 100 person-years.

Time-to-event analyses further showed that women with peritoneal endometriosis experienced a significantly shorter time to first birth than women with ovarian or combined/other endometriosis subtypes.

The authors concluded that these findings may assist clinicians in counseling women regarding reproductive outcomes after surgical diagnosis and treatment of endometriosis.

Research Source: https://pubmed.ncbi.nlm.nih.gov/41284521/