D'Hooghe, T. M., Debrock, S., Hill, J. A., & Meuleman, C. (2003). Endometriosis and subfertility: is the relationship resolved? Seminars in Reproductive Medicine, 21(2), 243-254. https://doi.org/10.1055/s-2003-41330
D'Hooghe TM, Debrock S, Hill JA, Meuleman C. Endometriosis and subfertility: is the relationship resolved? Semin Reprod Med. 2003;21(2):243-254. doi:10.1055/s-2003-41330
D'Hooghe, Thomas M., et al. "Endometriosis and subfertility: is the relationship resolved?" Seminars in Reproductive Medicine, vol. 21, no. 2, 2003, pp. 243-254.
Many lines of evidence link endometriosis to reduced fertility
A 2003 review of human and baboon studies argues that many signs point to endometriosis lowering fertility. About 33 out of 100 infertile women had it, against 4 out of 100 women of proven fertility. One trial found excising minimal to mild disease roughly doubled the monthly chance of pregnancy.
Key Findings
Laparoscopy found endometriosis in 781 of 2372 infertile women (33%) and 300 of 7953 previously fertile women (4%) in studies from 1988 to 2000 (P < 0.0001).
Endocan trial, 341 women with minimal to mild endometriosis: monthly fecundity rate 4.7% after excision, 2.4% after diagnostic laparoscopy (rate ratio 1.9, 95% CI, 1.2–3.1).
Endocan cumulative pregnancy rate at 36 weeks: 30.7% after excision, 17.7% after diagnostic laparoscopy (P= 0.006).
After donor insemination, cumulative pregnancy rate after 6 cycles was 20% against 55% in one study, and 38% against 80% in another (minimal-mild endometriosis against normal pelvis).
Without added treatment, the chance of conceiving and carrying a pregnancy past 20 weeks within 36 weeks was 15.7% with minimal to mild endometriosis and 23.6% with unexplained infertility (not significant).
Interpretation
This 2003 narrative review brings together human and baboon studies on endometriosis and fertility. In the Endocan trial, 341 women had minimal to mild endometriosis. Excision nearly doubled monthly fecundity: 4.7% after excision against 2.4% after diagnostic laparoscopy. Cumulative pregnancy at 36 weeks reached 30.7% after excision against 17.7% after diagnostic laparoscopy. Donor insemination data showed the same pattern in two more studies. Women with minimal to mild endometriosis conceived less often over six cycles than women with a normal pelvis. The authors note that no randomized trial yet includes women with moderate to severe disease. The findings support larger trials of excision in women with more severe endometriosis.
RRM Context
The review describes minimal to mild endometriosis as progressive in at least 30 to 60% of cases, with no way to predict which. Restorative reproductive medicine treats infertility by finding the disease and removing it. The progression data and the Endocan result both support that approach. Excision of lesions and adhesions produced the pregnancy gains.
Our editorial summary of this paper, not the article's abstract.
Abstract
There are many arguments to support the hypothesis that there is a causal relationship between the presence of endometriosis and subfertility. These arguments are reviewed in this article and include: (1) an increased prevalence of endometriosis in subfertile women compared with women of proven fertility; (2) a reduced monthly fecundity rate (MFR) in baboons with mild to severe (spontaneous or induced) endometriosis compared with those with minimal endometriosis or a normal pelvis; (3) a trend toward a reduced MFR in infertile women with minimal to mild endometriosis compared with women with unexplained infertility; (4) a dose-effect relationship: a negative correlation between the r-AFS stage of endometriosis and the monthly fecundity rate and crude pregnancy rate; (5) a reduced monthly fecundity rate and cumulative pregnancy rate after donor sperm insemination in women with minimal-mild endometriosis compared with those with a normal pelvis; (6) a reduced MFR after husband sperm insemination in women with minimal to mild endometriosis compared with those with a normal pelvis; (7) a reduced implantation rate per embryo after IVF in women with moderate to severe endometriosis compared with women with a normal pelvis; and (8) an increased monthly fecundity rate and cumulative pregnancy rate after surgical removal of minimal to mild endometriosis.
