A systematic review on endometriosis during pregnancy: diagnosis, misdiagnosis, complications and outcomes

BACKGROUND

Traditionally, pregnancy was considered to have a positive effect on endometriosis and its painful symptoms due not only to blockage of ovulation preventing bleeding of endometriotic tissue but also to different metabolic, hormonal, immune and angiogenesis changes related to pregnancy. However, a growing literature is emerging on the role of endometriosis in affecting the development of pregnancy and its outcomes and also on the impact of pregnancy on endometriosis. The present article aims to underline the difficulty in diagnosing endometriotic lesions during pregnancy and discuss the options for the treatment of decidualized endometriosis in relation to imaging and symptomatology; to describe all the possible acute complications of pregnancy caused by pre-existing endometriosis and evaluate potential treatments of these complications; to assess whether endometriosis affects pregnancy outcome and hypothesize mechanisms to explain the underlying relationships.

METHODS

This systematic review is based on material searched and obtained via Pubmed and Medline between January 1950 and March 2015. Peer-reviewed, English-language journal articles examining the impact of endometriosis on pregnancy and vice versa were included in this article.

RESULTS

Changes of the endometriotic lesions may occur during pregnancy caused by the modifications of the hormonal milieu, posing a clinical dilemma due to their atypical appearance. The management of these events is actually challenging as only few cases have been described and the review of available literature evidenced a lack of formal estimates of their incidence. Acute complications of endometriosis during pregnancy, such as spontaneous hemoperitoneum, bowel and ovarian complications, represent rare but life-threatening conditions that require, in most of the cases, surgical operations to be managed. Due to the unpredictability of these complications, no specific recommendation for additional interventions to the routinely monitoring of pregnancy of women with known history of endometriosis is advisable. Even if the results of the published studies are controversial, some evidence is suggestive of an association of endometriosis with spontaneous miscarriage, preterm birth and small for gestational age babies. A correlation of endometriosis with placenta previa (odds ratio from 1.67 to 15.1 according to various studies) has been demonstrated, possibly linked to the abnormal frequency and amplitude of uterine contractions observed in women affected. Finally, there is no evidence that prophylactic surgery would prevent the negative impact of endometriosis itself on pregnancy outcome.

CONCLUSIONS

Complications of endometriosis during pregnancy are rare and there is no evidence that the disease has a major detrimental effect on pregnancy outcome. Therefore, pregnant women with endometriosis can be reassured on the course of their pregnancies although the physicians should be aware of the potential increased risk of placenta previa. Current evidence does not support any modification of conventional monitoring of pregnancy in patients with endometriosis.

Obstetric outcomes in Chinese women with endometriosis: a retrospective cohort study

Background:

The effect of endometriosis on obstetric outcomes is still ambiguous. The aim of our study was to determine the association between endometriosis and adverse obstetric outcomes in a cohort of Chinese women.

Methods:

A retrospective cohort study was undertaken to compare obstetric outcomes between 249 women with endometriosis and 249 women without endometriosis. All women were nulliparous and achieved singleton pregnancies naturally. Women with endometriosis were diagnosed during surgery and confirmed histologically. Odds ratios (ORs) and 95% confidence intervals (CIs) of measures of obstetric outcomes were calculated.

Results:

Women with endometriosis showed significantly increased risks of preterm labor (adjusted OR, 2.42; 95% CI, 1.05–5.57), placenta previa (adjusted OR, 4.51; 95% CI, 1.23–16.50), and cesarean section (adjusted OR, 1.93; 95% CI, 1.31–2.84). No significant differences were observed in the incidence of pregnancy-induced hypertension, fetal growth restriction, small for gestational age, placental abruption, or luteal support in the first trimester between the two groups.

Conclusions:

Women with endometriosis are at a higher risk of preterm labor, placenta previa, and cesarean section during pregnancy and need additional care.

Infertility and reproductive disorders: impact of hormonal and inflammatory mechanisms on pregnancy outcome

BACKGROUND

Reproductive disorders and infertility are associated with the risk of obstetric complications and have a negative impact on pregnancy outcome. Affected patients often require assisted reproductive technologies (ART) to conceive, and advanced maternal age is a further confounding factor. The challenge is to dissect causation, correlation and confounders in determining how infertility and reproductive disorders individually or together predispose women to poor pregnancy outcomes.

METHODS

The published literature, to June 2015, was searched using PubMed, summarizing all evidences concerning the perinatal outcome of women with infertility and reproductive disorders and the potential mechanisms that may influence poor pregnancy outcome.

RESULTS

Reproductive disorders (endometriosis, adenomyosis, polycystic ovary syndrome and uterine fibroids) and unexplained infertility share inflammatory pathways, hormonal aberrations, decidual senescence and vascular abnormalities that may impair pregnancy success through common mechanisms. Either in combination or alone, these disorders results in an increased risk of preterm birth, fetal growth restriction, placental pathologies and hypertensive disorders. Systemic hormonal aberrations, and inflammatory and metabolic factors acting on endometrium, myometrium, cervix and placenta are all associated with an aberrant milieu during implantation and pregnancy, thus contributing to the genesis of obstetric complications. Some of these features have been also described in placentas from ART.

CONCLUSIONS

Reproductive disorders are common in women of childbearing age and rarely occur in isolation. Inflammatory, endocrine and metabolic mechanisms associated with these disorders are responsible for an increased incidence of obstetric complications. These patients should be recognized as 'high risk' for poor pregnancy outcomes and monitored with specialized follow-up. There is a real need for development of evidence-based recommendations about clinical management and specific obstetric care pathways for the introduction of prompt preventative care measures.

Impact of ovarian endometrioma on ovarian responsiveness and IVF: a systematic review and meta-analysis

In this systematic review and meta-analysis, the effect of ovarian endometrioma on ovarian responsiveness to stimulation and on assisted reproduction outcomes was evaluated. Nine published studies (1039 cases) were included. The number of oocytes retrieved (mean difference [MD] -1.50; 95% CI, -2.84 to -0.15, P = 0.03), metaphase II (MII) oocytes retrieved (MD -3.61; 95% CI -4.44 to -2.78, P < 0.00001) and total embryos formed (MD -0.66; 95% CI -1.13 to -0.18, P = 0.007) were significantly lower in women with ovarian endometrioma than the control group. Gonadotrophin dose, duration of stimulation, number of good-quality embryos, implantation rate, clinical pregnancy rate and live birth rate were similar. Comparisons between ovaries with endometriomas and healthy ovaries of the same individuals were also made. Number of oocytes retrieved, MII oocytes retrieved and total embryos formed were not statistically significantly different between the affected ovaries and contralateral normal ovaries. Observational studies showed that ovarian endometrioma was associated with fewer oocytes retrieved, fewer MII oocytes retrieved and fewer total formed embryos. Clinical pregnancy rate and live birth rates were not affected. Intra-patient comparisons in women with unilateral endometrioma suggested the number of oocytes retrieved, MII oocytes retrieved and total embryos formed were similar.

Factors associated with placenta praevia in primigravidas and its pregnancy outcome

Aim. To examine the factors associated with placenta praevia in primigravidas and also compare the pregnancy outcomes between primigravidas and nonprimigravidas. Method. A retrospective cohort study was conducted in women who underwent caesarean section for major placenta praevia in a tertiary university hospital from January 2007 till December 2013. Medical records were reviewed. Result. Among 243 with major placenta praevia, 56 (23.0%) were primigravidas and 187 (77.0%) were nonprimigravidas. Factors associated with placenta praevia in the primigravidas were history of assisted conception (P = 0.02) and history of endometriosis (P = 0.01). For maternal outcomes, the nonprimigravidas required earlier delivery than primigravidas (35.76 ± 2.54 weeks versus 36.52 ± 1.95 weeks, P = 0.03) and had greater blood loss (P = 0.04). A vast majority of the primigravidas had either posterior type II or type III placenta praevia. As for neonatal outcomes, the Apgar score at 1 minute was significantly lower for the nonprimigravidas (7.89 ± 1.72 versus 8.39 ± 1.288.39 ± 1.28, P = 0.02). Conclusion. This study highlighted that endometriosis and assisted conception were highly associated with placenta praevia in primigravida. Understanding the pregnancy outcomes of women with placenta praevia can assist clinicians in identifying patients who are at higher risk of mortality and morbidity. Identifying potential risk factors in primigravida may assist in counseling and management of such patients.

Impact of endometriosis and its staging on assisted reproduction outcome: systematic review and meta-analysis

OBJECTIVE

To evaluate whether the presence or severity of endometriosis affects the outcome of assisted reproductive techniques (ART).

METHODS

In this systematic review, all studies comparing the outcome of ART in women with and those without endometriosis, or at different stages of the disease, were considered eligible. We used either risk ratio (RR) or mean difference (MD) and their 95%CIs for comparisons. The primary outcome was live birth; the secondary outcome was clinical pregnancy. Miscarriage and the number of oocytes retrieved were examined as additional outcomes.

RESULTS

We included 92 studies in the review and 78 in the meta-analysis: 20,167 women with endometriosis were compared with 121,931 women without endometriosis, and 1703 women with Stage-III/IV endometriosis were compared with 2227 women with Stage-I/II endometriosis. The following results were observed for the comparison of women with endometriosis vs women without endometriosis: live birth, RR = 0.99 (95%CI, 0.92-1.06); clinical pregnancy, RR = 0.95 (95%CI, 0.89-1.02); miscarriage, RR = 1.31 (95%CI, 1.07-1.59); number of oocytes retrieved, MD = -1.56 (95%CI, -2.05 to -1.08). The following results were observed for the comparison of women with Stage-III/IV vs Stage-I/II endometriosis: live birth, RR = 0.94 (95%CI, 0.80-1.11); clinical pregnancy, RR = 0.90 (95%CI, 0.82-1.00); miscarriage, RR = 0.99 (95%CI, 0.73-1.36); number of oocytes retrieved, MD = -1.03 (95%CI, -1.67 to -0.39).

CONCLUSIONS

Women with endometriosis undergoing ART have practically the same chance of achieving clinical pregnancy and live birth as do women with other causes of infertility. No relevant difference was observed in the chance of achieving clinical pregnancy and live birth following ART when comparing Stage-III/IV with Stage-I/II endometriosis. The quality of the evidence for the additional examined outcomes was very low, not allowing meaningful conclusions to be drawn.

Obstetric Outcomes in Patients Treated for Deep Pelvic Endometriosis

Purpose

The aim of this study was to assess obstetric outcomes and symptoms during and after pregnancy in women submitted to surgical treatment for deep pelvic endometriosis.

Methods

We evaluated 123 women who underwent surgery for severe deep pelvic endometriosis-related symptoms. Interventions were excision of rectovaginal septum nodule with or without rectal or vaginal resection, or excision of nodule of uterosacral ligaments. On the basis of pregnancy desire, patients were submitted to a telephone interview and asked if there had been a pregnancy and its outcome. They were also asked to describe their pain symptoms before, after and during the pregnancy.

Results

From the 123 patients, we selected 43 women desiring pregnancy after surgery, who answered the telephone interview. Twenty-four patients (55.8%) got pregnant. We recorded 34 pregnancies a mean 21.8 ± 17.9 months after surgery. In the group of 25 full-term pregnancies, 14 women (56%) had a vaginal delivery without complications, and 11 (44%) underwent a cesarean section. In only 3 cases, was the indication of cesarean section related to previous surgery. Seventy-one percent of women treated without rectal or vaginal resection delivered vaginally. We also registered 1 case of uncomplicated vaginal delivery in a patient with vaginal resection and another 1 in a patient with rectal resection. In the patients who complained of pain before pregnancy, we observed a resolution of pain symptoms during pregnancy, but after delivery these symptoms reappeared.

Conclusions

In patients submitted to surgery for deep pelvic endometriosis, even in cases of vaginal or rectal resection, a cesarean section is not always mandatory.

[Adverse pregnancy outcomes after Assisted Reproduction Technology in women with endometriosis]

OBJECTIVE

While association between endometriosis and infertility is well established, there are few studies about the impact of endometriosis on adverse pregnancy outcomes. The aim of this study was to determine the effect of endometriosis on obstetric outcomes and whether the severity of the disease had an influence on these.

PATIENTS AND METHODS

We performed a retrospective study to investigate the obstetric outcomes of a population of 1204 subfertile women, including 258 with endometriosis, who obtained, thanks to assisted reproduction technology, a singleton pregnancy evolving beyond embryonic stage. Two analyzes were performed. The first compared women with endometriosis to women with other causes of infertility. The second observed adverse pregnancy outcomes according to AFS-R stages of endometriosis.

RESULTS

The overall rate of live birth children was 95.8%. In case of endometriosis, there was a significant increase of the incidence of preterm delivery, especially before 32 weeks amenorrhea (6.2% vs 3.1% in the group "without endometriosis", P = 0.03), antenatal bleeding (5.3% vs 2.2%, P = 0.01) and placenta previa (4.9% vs 0.9%, P < 0.0001). The incidence of gestational diabetes was significantly decreased (0.4% vs 2.7%, P = 0.04). There was no correlation between endometriosis and cesarean section or preeclampsia, or between the AFS-R stage and adverse pregnancy outcomes.

DISCUSSION AND CONCLUSION

Endometriosis is a factor of obstetrical risk, independently of the infertility it causes. The AFS-R score does not seem to be representative of obstetric outcomes beyond first trimester of pregnancy for women with endometriosis.

Do endometriomas induce an inflammatory reaction in nearby follicles?

STUDY QUESTION

Do endometriomas induce an inflammatory reaction with increased cytokine concentrations in nearby follicles and thereby affect follicular development during controlled ovarian stimulation for in vitro fertilization (IVF)?

SUMMARY ANSWER

With most endometriomas, there is no evidence of increased cytokine concentrations in the ipsilateral leading follicle. Infrequently, the concentration of inflammatory cytokines is increased in the follicular fluid (FF) and associated with diminished ovarian response.

WHAT IS KNOWN ALREADY

The link between peritoneal endometriosis, inflammation and infertility is well established; however, the association between intraovarian inflammation and endometrioma is unknown.

STUDY DESIGN, SIZE, DURATION

This prospective cohort study included 117 infertile women undergoing IVF in a tertiary infertility clinic at Oslo University Hospital Rikshospitalet, Norway, during the period May 2009 to September 2011.

PARTICIPANTS, SETTING, METHODS

There were 47 patients with unilateral endometrioma and 17 patients with bilateral endometrioma, while the 53 control patients had unexplained or male factor infertility. Concentrations of IL-1β, IL-6, IL-8, IL-10, IL-12 and TNF-α were measured in serum and in the fluid of the largest pre-ovulatory follicles from each ovary of each participant.

MAIN RESULTS AND THE ROLE OF CHANCE

Cytokine levels in the follicular fluid from the two ovaries in women with unilateral endometriomas were comparable, and were not significantly altered compared with that of control groups with male factor infertility, unexplained infertility or bilateral endometriomas. Compared with serum levels, the follicular fluid levels of IL-8 and IL-6 were higher, suggesting a local production or recruitment. The follicular fluid IL-8 level varied considerably and showed an inverse relationship with IL-12, IL-10 and TNF-∝, suggesting a complex interaction between various immune cells. A small group of patients (n = 3) had increased levels of all follicular fluid cytokines combined with moderately to slightly elevated serum levels and these patients had a significantly lower ovarian response.

LIMITATIONS, REASONS FOR CAUTION

For ethical reasons, the endometriomas were diagnosed indirectly by ultrasound rather than by histology.

WIDER IMPLICATIONS OF THE FINDINGS

This paper reveals that endometriomas seldom induce inflammation in nearby follicles during IVF; therefore, routine cystectomy prior to IVF may not be necessary. Cytokine levels in the follicular fluid, nonetheless, show distinctive patterns and increased levels may be linked to reduced ovarian response independent of the cause of infertility.