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Meta-Analysis
. 2020 Feb 11;2(2):CD001122.
doi: 10.1002/14651858.CD001122.pub5.

Laparoscopic ovarian drilling for ovulation induction in women with anovulatory polycystic ovary syndrome

Esmée M Bordewijk  1 , Ka Ying Bonnie Ng  2 , Lidija Rakic  1 , Ben Willem J Mol  3 , Julie Brown  4 , Tineke J Crawford  5 , Madelon van Wely  1
Affiliations
Meta-Analysis

Laparoscopic ovarian drilling for ovulation induction in women with anovulatory polycystic ovary syndrome

Esmée M Bordewijk et al. Cochrane Database Syst Rev. .

Abstract

Background: Polycystic ovary syndrome (PCOS) is a common condition affecting 8% to 13% of reproductive-aged women. In the past clomiphene citrate (CC) used to be the first-line treatment in women with PCOS. Ovulation induction with letrozole should be the first-line treatment according to new guidelines, but the use of letrozole is off-label. Consequently, CC is still commonly used. Approximately 20% of women on CC do not ovulate. Women who are CC-resistant can be treated with gonadotrophins or other medical ovulation-induction agents. These medications are not always successful, can be time-consuming and can cause adverse events like multiple pregnancies and cycle cancellation due to an excessive response. Laparoscopic ovarian drilling (LOD) is a surgical alternative to medical treatment. There are risks associated with surgery, such as complications from anaesthesia, infection, and adhesions.

Objectives: To evaluate the effectiveness and safety of LOD with or without medical ovulation induction compared with medical ovulation induction alone for women with anovulatory polycystic PCOS and CC-resistance.

Search methods: We searched the Cochrane Gynaecology and Fertility Group (CGFG) trials register, CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL and two trials registers up to 8 October 2019, together with reference checking and contact with study authors and experts in the field to identify additional studies.

Selection criteria: We included randomised controlled trials (RCTs) of women with anovulatory PCOS and CC resistance who underwent LOD with or without medical ovulation induction versus medical ovulation induction alone, LOD with assisted reproductive technologies (ART) versus ART, LOD with second-look laparoscopy versus expectant management, or different techniques of LOD.

Data collection and analysis: Two review authors independently selected studies, assessed risks of bias, extracted data and evaluated the quality of the evidence using the GRADE method. The primary effectiveness outcome was live birth and the primary safety outcome was multiple pregnancy. Pregnancy, miscarriage, ovarian hyperstimulation syndrome (OHSS), ovulation, costs, and quality of life were secondary outcomes.

Main results: This updated review includes 38 trials (3326 women). The evidence was very low- to moderate-quality; the main limitations were due to poor reporting of study methods, with downgrading for risks of bias (randomisation and allocation concealment) and lack of blinding. Laparoscopic ovarian drilling with or without medical ovulation induction versus medical ovulation induction alone Pooled results suggest LOD may decrease live birth slightly when compared with medical ovulation induction alone (odds ratio (OR) 0.71, 95% confidence interval (CI) 0.54 to 0.92; 9 studies, 1015 women; I2 = 0%; low-quality evidence). The evidence suggest that if the chance of live birth following medical ovulation induction alone is 42%, the chance following LOD would be between 28% and 40%. The sensitivity analysis restricted to only RCTs with low risk of selection bias suggested there is uncertainty whether there is a difference between the treatments (OR 0.90, 95% CI 0.59 to 1.36; 4 studies, 415 women; I2 = 0%, low-quality evidence). LOD probably reduces multiple pregnancy rates (Peto OR 0.34, 95% CI 0.18 to 0.66; 14 studies, 1161 women; I2 = 2%; moderate-quality evidence). This suggests that if we assume the risk of multiple pregnancy following medical ovulation induction is 5.0%, the risk following LOD would be between 0.9% and 3.4%. Restricting to RCTs that followed women for six months after LOD and six cycles of ovulation induction only, the results for live birth were consistent with the main analysis. There may be little or no difference between the treatments for the likelihood of a clinical pregnancy (OR 0.86, 95% CI 0.72 to 1.03; 21 studies, 2016 women; I2 = 19%; low-quality evidence). There is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage (OR 1.11, 95% CI 0.78 to 1.59; 19 studies, 1909 women; I2 = 0%; low-quality evidence). OHSS was a very rare event. LOD may reduce OHSS (Peto OR 0.25, 95% CI 0.07 to 0.91; 8 studies, 722 women; I2 = 0%; low-quality evidence). Unilateral LOD versus bilateral LOD Due to the small sample size, the quality of evidence is insufficient to justify a conclusion on live birth (OR 0.83, 95% CI 0.24 to 2.78; 1 study, 44 women; very low-quality evidence). There were no data available on multiple pregnancy. The likelihood of a clinical pregnancy is uncertain between the treatments, due to the quality of the evidence and the large heterogeneity between the studies (OR 0.57, 95% CI 0.39 to 0.84; 7 studies, 470 women; I2 = 60%, very low-quality evidence). Due to the small sample size, the quality of evidence is not sufficient to justify a conclusion on miscarriage (OR 1.02, 95% CI 0.31 to 3.33; 2 studies, 131 women; I2 = 0%; very low-quality evidence). Other comparisons Due to lack of evidence and very low-quality data there is uncertainty whether there is a difference for any of the following comparisons: LOD with IVF versus IVF, LOD with second-look laparoscopy versus expectant management, monopolar versus bipolar LOD, and adjusted thermal dose versus fixed thermal dose.

Authors' conclusions: Laparoscopic ovarian drilling with and without medical ovulation induction may decrease the live birth rate in women with anovulatory PCOS and CC resistance compared with medical ovulation induction alone. But the sensitivity analysis restricted to only RCTs at low risk of selection bias suggests there is uncertainty whether there is a difference between the treatments, due to uncertainty around the estimate. Moderate-quality evidence shows that LOD probably reduces the number of multiple pregnancy. Low-quality evidence suggests that there may be little or no difference between the treatments for the likelihood of a clinical pregnancy, and there is uncertainty about the effect of LOD compared with ovulation induction alone on miscarriage. LOD may result in less OHSS. The quality of evidence is insufficient to justify a conclusion on live birth, clinical pregnancy or miscarriage rate for the analysis of unilateral LOD versus bilateral LOD. There were no data available on multiple pregnancy.

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Conflict of interest statement

Esmée Bordewijk: none known Ka Ying Bonnie Ng: none known Lidija Rakic: none known Ben Willem Mol reports grants from NHMRC, personal fees from ObsEva, personal fees from Merck Merck KGaA, personal fees from Guerbet, personal fees from iGenomix, outside the submitted work. Julie Brown: none known Tineke Crawford: none known Madelon van Wely: none known

Figures

1
1
Study flow diagram.
2
2
Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
3
3
Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
4
4
Forest plot of comparison: 1 LOD with and without medical ovulation versus medical ovulation alone, outcome: 1.1 Live birth. MOI: Medical ovulation induction alone LOD: laparoscopic ovarian drilling with or without medical ovulation induction
5
5
Funnel plot of comparison: 1 LOD with and without medical ovulation versus medical ovulation alone, outcome: 1.1 Live birth. LOD: laparoscopic ovarian drilling with or without medical ovulation induction
6
6
Forest plot of comparison: 5 Sensitivity analysis low risk of bias: LOD with and without medical ovulation versus medical ovulation alone, outcome: 5.1 Live birth. MOI: Medical ovulation induction alone LOD: laparoscopic ovarian drilling with or without medical ovulation induction
7
7
Forest plot of comparison: 1 LOD with and without medical ovulation versus medical ovulation alone, outcome: 1.4 Multiple pregnancy rate (per ongoing pregnancy). MOI: Medical ovulation induction alone LOD: laparoscopic ovarian drilling with or without medical ovulation induction
1.1
1.1. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 1 Live birth.
1.2
1.2. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 2 Multiple pregnancy.
1.3
1.3. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 3 Clinical pregnancy.
1.4
1.4. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 4 Miscarriage.
1.5
1.5. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 5 OHSS.
1.6
1.6. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 6 Ovulation.
1.7
1.7. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 7 Costs.
1.8
1.8. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 8 Quality of Life (Health related quality of life: SF‐36).
1.9
1.9. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 9 Quality of life (Rotterdam Symptom Checklist at 24 weeks).
1.10
1.10. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 10 Quality of life (Depression scales (CES‐D) at 24 weeks).
1.11
1.11. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 11 Multiple pregnancy per pregnancy.
1.12
1.12. Analysis
Comparison 1 LOD with and without medical ovulation versus medical ovulation alone, Outcome 12 Miscarriage per pregnancy.
2.1
2.1. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 1 Live birth.
2.2
2.2. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 2 Multiple pregnancy.
2.3
2.3. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 3 Clinical pregnancy.
2.4
2.4. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 4 Miscarriage.
2.5
2.5. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 5 OHSS.
2.6
2.6. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 6 Multiple pregnancy per pregnancy.
2.7
2.7. Analysis
Comparison 2 LOD + IVF versus IVF, Outcome 7 Miscarriage per pregnancy.
3.1
3.1. Analysis
Comparison 3 LOD + second‐look laparoscopy versus LOD + expectant management, Outcome 1 Clinical pregnancy.
3.2
3.2. Analysis
Comparison 3 LOD + second‐look laparoscopy versus LOD + expectant management, Outcome 2 Miscarriage.
3.3
3.3. Analysis
Comparison 3 LOD + second‐look laparoscopy versus LOD + expectant management, Outcome 3 Ovulation.
3.4
3.4. Analysis
Comparison 3 LOD + second‐look laparoscopy versus LOD + expectant management, Outcome 4 Miscarriage per pregnancy.
4.1
4.1. Analysis
Comparison 4 Unilateral versus bilateral, Outcome 1 Live birth.
4.2
4.2. Analysis
Comparison 4 Unilateral versus bilateral, Outcome 2 Clinical pregnancy.
4.3
4.3. Analysis
Comparison 4 Unilateral versus bilateral, Outcome 3 Miscarriage.
4.4
4.4. Analysis
Comparison 4 Unilateral versus bilateral, Outcome 4 Ovulation.
4.5
4.5. Analysis
Comparison 4 Unilateral versus bilateral, Outcome 5 Miscarriage per pregnancy.
5.1
5.1. Analysis
Comparison 5 Monopolar versus bipolar, Outcome 1 Clinical pregnancy.
5.2
5.2. Analysis
Comparison 5 Monopolar versus bipolar, Outcome 2 Ovulation.
6.1
6.1. Analysis
Comparison 6 Adjusted thermal dose versus fixed thermal dose, Outcome 1 Clinical pregnancy.
6.2
6.2. Analysis
Comparison 6 Adjusted thermal dose versus fixed thermal dose, Outcome 2 Miscarriage.
6.3
6.3. Analysis
Comparison 6 Adjusted thermal dose versus fixed thermal dose, Outcome 3 Ovulation.
7.1
7.1. Analysis
Comparison 7 Sensitivity analysis low risk of bias: LOD with and without medical ovulation versus medical ovulation alone, Outcome 1 Live birth.
7.2
7.2. Analysis
Comparison 7 Sensitivity analysis low risk of bias: LOD with and without medical ovulation versus medical ovulation alone, Outcome 2 Multiple pregnancy.
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References

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Franz 2016 {published data only}
    1. Franz M, Marschalek J, Ott J, Pavlik R, Watrelot A, Thaler CJ. A comparison of transabdominal versus transvaginal laparoscopic ovarian drilling for polycystic ovary syndrome. Geburtshilfe Frauenheilkd 2016;76:216. [DOI: 10.1055/s-0036-1592765] - DOI
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Greenblatt 1993 {published data only}
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Heylen 1994 {published data only}
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Kamel 2004 {published data only}
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Kandil 2018 {published data only}
    1. Kandil M, Rezk M, Al‐Halaby A, Emarh M, El‐Nasr IS. Impact of ultrasound‐guided transvaginal ovarian needle drilling versus laparoscopic ovarian drilling on ovarian reserve and pregnancy rate in polycystic ovary syndrome: a randomized clinical trial. Journal of Minimally Invasive Gynecology 2018;25(6):1075‐9. [DOI: 10.1016/j.mig.2018.01.036] - DOI - PubMed
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Kocak 2006 {published data only}
    1. Kocak I, Ustun C. Effects of metformin on insulin resistance, androgen concentration, ovulation and pregnancy rates in women with polycystic ovary syndrome following laparoscopic ovarian drilling. Journal of Obstetrics and Gynaecology Research 2006; Vol. 32, issue 3:292‐8. - PubMed
Lockwood 1995 {published data only}
    1. Lockwood G, Ledger W, Barlow D. Randomised cross over trial to assess the efficacy of 3 alternative treatments for ovulation induction in infertile women with clomiphene resistant polycystic ovarian syndrome (PCOS). Abstracts of 15th World Congress on Fertility and Sterility. Montpellier (France), 1995.
Malkawi 2005 {published data only}
    1. Malkawi HY, Qublan HS. Laparoscopic ovarian drilling in the treatment of polycystic ovary syndrome: how many punctures per ovary are needed to improve the reproductive outcomes. Journal of Obstetrics and Gynaecology Research 2005;31:115‐9. - PubMed
Muenstermann 2000 {published data only}
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Nasr 2010 {published data only}
    1. Nasr A. Effect of N‐acetyl‐cysteine after ovarian drilling in clomiphene citrate resistant PCOS women: a pilot study. Reproductive BioMedicine Online 2010;20(3):403‐9. - PubMed
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Roy 2018 {published data only}
    1. Roy KK, Maddirala H, Kumar S, Singhal S, Meena J. Evaluation of laparoscopic ovarian drilling by harmonic scalpel versus monopolar drilling needle in cases of clomiphene citrate resistant polycystic ovarian response. Journal of Minimally Invasive Gynecology 2018;25(7):S1–S256. [DOI: 10.1016/j.jmig.2018.09.383] - DOI
Salah 2013 {published data only}
    1. Salah IM. Office microlaparoscopic ovarian drilling (OMLOD) versus conventional laparoscopic ovarian drilling (LOD) for women with polycystic ovary syndrome. Archives of Gynecology and Obstetrics 2013;287(2):361‐7. - PubMed
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Seyam 2018 {published data only}
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Sunj 2013 {published data only}
    1. Sunj M, Canic T, Baldani DP, Tandara M, Jeroncic A, Palada I. Does unilateral laparoscopic diathermy adjusted to ovarian volume increase the chances of ovulation in women with polycystic ovary syndrome?. Human Reproduction 2013;28(9):2417‐24. - PubMed
    1. Sunj M, Canic T, Jeroncic A, Karelovic D, Tandara M, Juric S, et al. Anti‐Mullerian hormone, testosterone and free androgen index following the dose‐adjusted unilateral diathermy in women with polycystic ovary syndrome. European Journal of Obstetrics, Gynecology, and Reproductive Biology 2014;179:163‐9. - PubMed
Tabrizi 2005 {published data only}
    1. Tabrizi NM, Mohammad K, Dabirashrafi H, Nia FI, Salehi P, Dabirashrafi B, et al. Comparison of 5‐, 10‐, and 15‐point laparoscopic ovarian electrocauterization in patients with polycystic ovarian disease: a prospective, randomized study. JSLS: Journal of the Society of Laparoendoscopic Surgeons 2005;9(4):439‐41. - PMC - PubMed
Vrbikova 1998 {published data only}
    1. Vrbikova J, Kuzel D, Rezabek K, Zivny J, Starka L, Vondra K, et al. Endocrine‐metabolic changes after different extents of laparoscopic ovarian drilling in clomiphene citrate resistant PCOS women (Abstract only). Fertility and Sterility 1998;70(Suppl 1):5497‐8.
Wang 2015 {published data only}
    1. Wang XH, Wang JQ, Xu Y, Huang LP. Therapeutic effects of metformin and laparoscopic ovarian drilling in treatment of clomiphene and insulin‐resistant polycystic ovary syndrome. Archives of Gynecology and Obstetrics 2015;291(5):1089‐94. - PubMed
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References to studies awaiting assessment

Abu Hashim 2010a {published data only}
    1. Abu Hashim H, Mashaly AM, Badawy A. Letrozole versus laparoscopic ovarian diathermy for ovulation induction in clomiphene resistant women with polycystic ovary syndrome: A randomized controlled trial. Archives of Gynecology and Obstetrics 2010;282(5):567‐71. - PubMed
Abu Hashim 2011a {published data only}
    1. Abu Hashim H, Lakany N, Sherief L. Combined metformin and clomiphene citrate versus laparoscopic ovarian diathermy for ovulation induction in clomiphene‐resistant women with polycystic ovary syndrome: A randomized controlled trial. The Journal of Obstetrics and Gynaecology Research 2011;37(3):169‐77. - PubMed

References to ongoing studies

IRCT138903291306N2 {unpublished data only}
    1. IRCT138903291306N2. Comparison of ovulation rate after laparoscopic electrocautery in infertile women with Clomiphene citrate resistant polycystic ovarian syndrome. en.irct.ir/trial/538 (first received 3 October 2010).
NCT02239107 {unpublished data only}
    1. NCT02239107. N‐acetyl cysteine for ovulation induction in clomiphene citrate resistant polycystic ovary syndrome. clinicaltrials.gov/ct2/show/NCT02239107 (first received 12 September 2014).
NCT02305693 {unpublished data only}
    1. NCT02305693. Comparison between letrozole and laparoscopic ovarian drilling in women with clomiphene resistant polycystic ovarian syndrome. clinicaltrials.gov/ct2/show/NCT02305693 (first received 3 December 2014).
NCT02381184 {unpublished data only}
    1. NCT02381184. Extended clomiphene citrate regimen versus laparoscopic ovarian drilling for ovulation induction in clomiphene citrate‐resistant women with polycystic ovary syndrome. clinicaltrials.gov/ct2/show/NCT02381184 (first received 6 March 2015).
NCT02775734 {unpublished data only}
    1. NCT02775734. N‐acetyl‐cysteine in clomiphene citrate resistant polycystic ovary syndrome after laparoscopic ovarian drilling: a randomized controlled trial. clinicaltrials.gov/ct2/show/NCT02775734 (first received 18 May 2016).
NCT03009838 {unpublished data only}
    1. NCT03009838. Letrozole versus laparoscopic ovarian drilling in polycystic ovary syndrome. clinicaltrials.gov/ct2/show/NCT03009838 (first received 4 January 2017).
NCT03206892 {unpublished data only}
    1. NCT03206892. LESS surgery versus conventional multiport laparoscopy in ovarian drilling. clinicaltrials.gov/ct2/show/NCT03206892 (first received 2 July 2017).
NCT03664050 {unpublished data only}
    1. NCT03664050. Laparoscopic ovarian drilling versus letrozole in clomiphene citrate resistant polycystic ovary. clinicaltrials.gov/ct2/show/NCT03664050 (first received 10 September 2018).
PACTR201411000886127 {unpublished data only}
    1. PACTR201411000886127. Impact of unilateral vesus bilateral laparoscopic ovarian drilling on ovarian reserve and pregnancy rate: a randomized clinical trial. http://apps.who.int/trialsearch/Trial3.aspx?trialid=PACTR201411000886127 (first received 13 September 2014). - PubMed

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References to other published versions of this review

Farquhar 2001
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