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ORIGINAL ARTICLE
Year : 2016  |  Volume : 3  |  Issue : 3  |  Page : 115-120

Relationship between uterine scoring system for reproduction and pregnancy in controlled ovarian stimulation-intrauterine insemination cycles


Department of Obstetrics and Gynaecology, A. J. Institute of Medical Sciences and Research Centre, Mangalore, Karnataka, India

Date of Web Publication21-Apr-2017

Correspondence Address:
R Nayak Navinchandra
202, ARIA Apartments, Alvares Road, Kadri, Mangalore - 575 002, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2348-2907.204669

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  Abstract 


Aims: (1) Evaluation of uterine scoring system for reproduction (USSR) score in controlled ovarian stimulation-intrauterine insemination (COS-IUI) cycles. (2) Evaluation of the relationship between USSR score and pregnancy in COS-IUI cycles. Settings and Design: Prospective observational study. Materials and Methods: The study comprised women visiting the department with unexplained infertility for a COS-IUI cycle. A total of 30 cycles were inducted. Baseline transvaginal sonography (TVS) was performed on day 2 of the cycle. Stimulation was performed with clomiphene citrate (50 or 100 mg). On day 5, the recruitment and dominance of follicles were studied by TVS. In the absence of dominance and/or in need of increase in recruitment, urinary gonadotropin was administered. TVS was repeated every 2 days until the dominant follicle was 15 mm and then on a daily basis till follicle reached 18 mm. USSR score was then evaluated and injection. Human chorionic gonadotropin (HCG) 10,000 units was given for follicular rupture. IUI was done 34–36 h posttrigger with prepared semen samples containing at least 15 million motile sperms. Women with serum β HCG values of ≥ 25 IU/ml on the 16th post-IUI day were pregnancy positive. Statistical Analysis: Chi-square test. Results: None had a USSR score of 20. Two had a score of 17–19, two had score of 14–16, 26 had a score of ≤13. Of the 30 women, three conceived. Two of the three had a score of 17 and one had a score of 16. Conclusions: USSR can prove to be a simple, noninvasive, and authentic score to predict the uterine environment and help in the prediction of outcome.

Keywords: Controlled ovarian stimulation-intrauterine insemination cycle, infertility, uterine scoring system for reproduction


How to cite this article:
Navinchandra R N, Shankar ST, Kavitha D, Kamath MG, Devdas SP, Vineela P. Relationship between uterine scoring system for reproduction and pregnancy in controlled ovarian stimulation-intrauterine insemination cycles. IVF Lite 2016;3:115-20

How to cite this URL:
Navinchandra R N, Shankar ST, Kavitha D, Kamath MG, Devdas SP, Vineela P. Relationship between uterine scoring system for reproduction and pregnancy in controlled ovarian stimulation-intrauterine insemination cycles. IVF Lite [serial online] 2016 [cited 2019 Sep 16];3:115-20. Available from: http://www.ivflite.org/text.asp?2016/3/3/115/204669




  Introduction Top


Infertility is a sad problem which victimizes women with an inability to conceive.[1] Endometrial receptivity can be defined as a unique sequence of factors that make the endometrium receptive to the embryonic implantation.[2] Implantation is a well-organized and orchestrated process [3] that contributes significantly to a successful pregnancy. Among the various molecular and sonographic markers which have been proposed to evaluate endometrial receptivity, transvaginal ultrasonography is a simple, reliable, and inexpensive yet effective method to evaluate endometrial receptivity and predict pregnancy.[4] The sonographic findings which may help to predict the outcome have been weighed by many, but the uterine scoring system for reproduction (”USSR”) by Michael [5] has been extensively used in assisted reproductive technique cycles.


  Materials and Methods Top


Source of data

Hospital-based prospective observational study was conducted during controlled ovarian stimulation-intrauterine insemination (COS-IUI) treatment cycles for couples visiting the outpatient department at a medical college hospital with the complaints of inability to conceive even after 1 year of regular unprotected coitus and with all baseline investigations (transvaginal pelvic ultrasonography, tubal patency test, day 2 follicle stimulating hormone [FSH], luteinizing hormone [LH], semen analysis, serum prolactin, and thyroid stimulating hormone [TSH]) within normal limits. A total of thirty cycles were studied.

Method of collection of data

Following a written informed consent as per the WHO guidelines from couples willing to be a part of the study, the history, examination and investigation findings were noted. A baseline transvaginal sonography (TVS) was performed on female on day 2 of her spontaneous cycle. In the event of a normal day 2 scan, she was stimulated with clomiphene citrate (50 or 100 mg) depending on her antral follicle count.

In the absence of dominance and in need for an increase in recruitment, urinary gonadotrophin was administered.

She was re-evaluated on day 5 of the cycle for recruitment and dominance of follicles.

Subsequently, follicular growth was monitored every 2 days until the dominant or lead follicle was 15 mm in diameter.

Monitoring was then undertaken on a daily basis till the follicle attained a diameter of 18 mm.

The USSR score was evaluated, and injection human chorionic gonadotrophin (HCG) was administered as ovulation trigger.

IUI was planned 34–36 h posttrigger. The USSR score was re-evaluated just before the IUI and IUI was done with prepared semen samples with at least 15 million motile sperms. Post-IUI luteal support with micronized progesterone was provided.

On the 16th post-IUI day, beta HCG values were estimated, and values of 25 IU/ml and above were considered pregnancy positive. All data were statistically analyzed.

Selection criteria

Inclusion criteria

  1. COS-IUI cycles in couples with unexplained infertility.


Exclusion criteria

  1. FSH and LH >10 mIU/ml
  2. FSH: LH ratio <1
  3. Prolactin >20 ng/ml
  4. TSH >3 μ IU/ml
  5. Husband's semen count of <15 million/ml or 40 million/ejaculate with progressive motility of <40%
  6. Tubal patency test suggestive of blocked tubes
  7. TVS suggestive of abnormalities of the uterus, uterine polyp, abnormalities of the ovaries, or any other pelvic pathology.


Appendix

The USSR by Michael Applebaum is calculated as follows [1]

These include seven parameters:

  1. Endometrial thickness (full-thickness measured from the myometrial-endometrial junction to the endometrial-myometrial junction)
  2. Endometrial layering (i.e., a 5-line appearance)
  3. Myometrial contractions (seen as endometrial motion)
  4. Myometrial echogenicity
  5. Uterine artery Doppler flow evaluation
  6. Endometrial blood flow
  7. Gray-scale myometrial blood flow.


According to Applebaum, the endometrial and peri-endometrial areas are divided in terms of endometrial vascularity into the following four zones:

  1. Zone 1: A 2 mm thick area surrounding the hyperechoic outer layer of the endometrium
  2. Zone 2: The hyperechoic outer layer of the endometrium
  3. Zone 3: The hypoechoic inner layer of the endometrium
  4. Zone 4: The endometrial cavity.


Each parameter is scored as follows:

  1. Endometrial thickness:


    1. <7 mm = 0,
    2. 7–9 mm = 2,
    3. 10–14 mm = 3,
    4. >14 mm = 1.


  2. Endometrial layering:


    1. No layering = 0,
    2. Hazy 5-line/tri laminar appearance = 1,
    3. Distinct 5-line/tri laminar appearance = 3.


  3. Myometrial contractions (seen as wave-like endometrial motion):


    1. <3 contractions in 2 min (real-time) =0,
    2. >3 contractions in 2 min (real-time) =3.


  4. Myometrial echogenicity:


    1. Coarse/inhomogeneous echogenicity = 1,
    2. Relatively homogeneous echogenicity = 2.


  5. Uterine artery Doppler flow evaluation (pulsatility index [PI]):


    1. PI > 3.0 = 0,
    2. PI < 2.5–2.99 = 0,
    3. PI < 2.2–2.49 = 1,
    4. PI < 2.19 = 2.


  6. Endometrial blood flow within zone 3:


    1. Absent = 0,
    2. Present, but sparse = 2,
    3. Present multifocally = 5.


  7. Myometrial blood flow internal to the arcuate vessels seen on gray-scale examination:


  1. Absent = 0,
  2. Present = 2.



  Results Top


In this study, a total of thirty cycles were studied. When the USSR score was estimated, no woman had a perfect USSR score of 20. There were 2 (6.7%) women with a score of 17–19 and both were pregnancy positive (100%). There were 2 (6.7%) with a score of 14–16 and only one of them was pregnancy positive (50%). Twenty-six (86.7%) had a score of ≤ 13 and none of them were pregnancy positive [Table 1].
Table 1: Distribution of study subjects as per uterine scoring system for reproduction score (n=30)

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As far as endometrial thickness was concerned, the best score of 3 with a thickness of 10–14 mm was secured by 11 (36.7%) and one was pregnancy positive (9.09%). Eighteen (60%) had a score of 2 with a thickness of 7–9 mm and two of them were pregnancy positive (11%) and 1 (3.3%) had a score of 1 with a thickness of >14 and was not positive for pregnancy [Table 2].
Table 2: Distribution of study subjects as per endometrial thickness (n=30)

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When endometrial blood flow zone 3 was studied, multifocal flow carrying the best score of 5 was seen in 8 (23.3%) women and 2 (25%) of them conceived. Twenty-two (76.7%) had sparse flow which carried a score of 2 and 1 (4.5%) of them conceived [Table 3].
Table 3: Distribution of study subjects as per endometrial blood fl ow zone 3 (n=30)

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Evaluation of endometrial layering revealed that 11 (36.7%) showed a distinct 5 line carrying a score of 3 and 3 (27.2%) of them were pregnancy positive. Nineteen (63.3%) showed a hazy five line carrying a score of 1 and none of them had a pregnancy [Table 4].
Table 4: Distribution of study subjects as per endometrial layering (n=30)

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Myometrial contraction of > 3 in 2 min carrying a score of 3 was seen in 4 (13.3%) and 3 (75%) of them had a positive pregnancy. All 26 (86.7%) women with myometrial contractions < 3 in 2 min carrying a score of 0 were negative for pregnancy [Table 5].
Table 5: Distribution of study subjects as per myometrial contraction (n=30)

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Homogenous myometrial echo with a score of 2 was seen in 2 (6.7%) women and both (100%) had a positive pregnancy. Inhomogenous echo with a score of 1 was seen in 28 (93.3%) and 1 (3.5%) among them conceived [Table 6].
Table 6: Distribution of study subjects as per myometrial echo (n=30)

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The presence of myometrial blood flow carrying a score of 2 was seen in 4 (13.3%) women and 3 (75%) of them conceived. Twenty-six (86.7%) women had absent myometrial blood flow and none of them were positive for pregnancy [Table 7].
Table 7: Distribution of study subjects as per myometrial blood fl ow (n=30)

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Uterine artery PI was <2.49 with a score of 2 was found in 1 (3.3%) woman who was positive for pregnancy (100%). PI of 2.2–2.49 with a score of 1 was seen in 3 (10%) women and 2 (66.67%) of them conceived. PI of 2.5–2.99 with a score of 0 was seen in 26 (86.7%) and there were no positive pregnancies in this group [Table 8].
Table 8: Distribution of study subjects as per uterine artery pulsatility index (n=30)

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When the results were statistically analyzed, it was found that USSR score of 17–19 was highly significant (HS) for a pregnancy and a score of 14–16 was significant for a pregnancy. A score of <13 significantly ruled out the possibility of a pregnancy. On an individual basis, the following parameters, that is, myometrial contractions, myometrial echo, myometrial blood flow, and uterine artery PI, were HS for a pregnancy, but endometrial thickness and the endometrial blood flow were not found to be significant in predicting pregnancy on the basis of Z-score and P value [Table 9].
Table 9: Correlation of the parameters based on Chi-square test

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  Discussion Top


Endometrial receptivity plays a crucial role in implantation of embryo and evaluation of endometrial receptivity remains a challenge in clinical practice.

According to study conducted by Malhotra et al.[6] in spontaneous cycles of 222 women, USSR score of twenty gave 80% of pregnancy rate and a score of 17–19 gave 79% of conception. While only 7.6% conceived with a score of ≤13.[1]

In this study, no woman had a perfect score of twenty, whereas the pregnancy rate for patients with a score of 17–19 was 100% and for those with a score of 14–16 was 50%. All women with a score of ≤13 were negative for pregnancy. Greater USSR score gave a better conception outcome which made it a reliable parameter for prediction.

According to a study conducted by Strowitzki et al.[7] revealed that inadequate endometrium can be considered as a main fertility determining factor.[1]

Multiple studies have supported or refuted the relationship between endometrial features such as thickness, length, or pattern and the implantation rate (Bassil, 2001; Kovacs et al., 2003; Richter et al., 2007; Zhang et al., 2005; Rinaldi et al., 1996).[8],[9],[10],[11],[12]

In this study, pregnancy was positive when the endometrium was in the range of 7–14 mm. There were 18 women with an endometrial thickness of 7–9 mm and the pregnancy rate was 11.1%, whereas 11 women with a thickness of 10–14 mm showed a pregnancy rate of 9.09%. Therefore, on an individual basis endometrial thickness all by itself was not a reliable parameter to predict a pregnancy.

This was in accordance with a study carried out by Gupta et al. where maximum conception rate (60%) was seen with an endometrial thickness of 7–9 mm.[1]

Some studies have supported the idea that only embryo quality is the best predictive factor for conception in in vitro fertilization (IVF) cycles (Brezinova et al., 2009; Fauque et al., 2007),[13],[14] significantly better than the assessment of endometrium (Terriou et al., 2007; Terriou et al., 2001; Zhang et al., 2005).[11],[15],[16]

In this study, eight women had multifocal endometrial blood flow in zone 3 and 2 (25%) of them conceived, whereas twenty two had sparse endometrial blood flow zone 3 out of whom, 1 (4.5%) conceived. Endometrial blood flow was found to have no statistical significance for predicting a pregnancy in this study.

According to Gupta et al., endometrial blood flow of zone 4 gave the highest conception rate of 66.6% and was 54.5% with zone 3. While patients with endometrial blood flow only till zone 1 gave lowest, that is, 11.1% conception rate.[1]

According to a study, successful embryo implantation requires a genetically and morphologically healthy embryo as well as developed receptive endometrium.[17]

In a prospective study by Serafimi et al. (1994), the multi-layered pattern of the endometrium was more predictive of implantation than any other parameter.[2]

Study done in 1989 by Welker et al. reported that if the ultrasound appearance was of an outer hyper echogenic and inner hypo echogenic layer, the pregnancy rate was significantly higher (Fanchin et al., 1999, 2000).[18],[19]

In our study, 11 (36.7%) women had a distinct five line appearance of the endometrium carrying a score of 3 and 3 (27.2%) of them were pregnancy positive.

In our study, uterine artery PI of <2.49 with a score of 2 was seen in 1 (100%) woman and she was pregnancy positive while the pregnancy rate with a PI of 2.2–2.49 was 66.67% (2 out of 3).

This was in accordance with a study done by Sterzic et al. in 1989; Steer 2005, Coulam et al. in 1994, who reported that based on uterine artery PI patients who became pregnant had a lower vascular impedance less than 2.99 compared to those who did not (Yuval et al., 1999).[20]

As per a study by Sohail in 2005, no significant correlation was found with any of the individual variables including the endometrial and myometrial characteristics, as well as the uterine artery flow. Myometrial contraction was the most technically difficult parameter to be observed.[21]

In this study, statistical analysis for myometrial characteristics, namely, myometrial contractions, myometrial echo, and myometrial blood flow suggested that these parameters were HS in predicting a positive pregnancy.

Myometrial contractions >3 in 2 min and the presence of myometrial blood flow was seen in four women and three of them were pregnancy positive. Homogenous myometrial echogenicity was seen in three women and all three of them conceived.

Most of the studies cited above have been conducted in IVF/intracytoplasmic sperm injection (ICSI) cycles. Taking into consideration that IUI cycles differ significantly from IVF/ICSI cycles with respect to levels of stimulation it seemed appropriate to design this study which co related USSR scores and pregnancy in IUI cycles in unexplained infertility.


  Conclusions Top


USSR can prove to be a simple, noninvasive and authentic score to predict the uterine environment and thereby helping in the prediction of the outcome even in COS-IUI cycles. Four out of the seven parameters were found to be HS to predict a pregnancy all by themselves, but these parameters needed expertise and better instrumentation for evaluation. Of the remaining three parameters, one was significant on an individual basis and two were found to be not significant on an individual basis. The expertise needed for evaluation of USSR score and the type of instrumentation have not been evaluated in this study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no confl icts of interest.



 
  References Top

1.
Gupta P, Chandra S, Kaushik A, Jain PK. Evaluation of Uterine Biophysical Profile and to Assess its Role in Predicting Conception among Unexplained Primary Infertility Patients. Indian J Community Health 2014;26:401-4.  Back to cited text no. 1
    
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Ivanovski M. The Role of Ultrasound in the Evaluation of Endometrial Receptivity Following Assisted Reproductive Treatments [Internet]. www.intechtopen.com. 2012 [last accessed 5 April 2017]. Available from:Mitko Ivanovski (2012). The Role of Ultrasound in the Evaluation of Endometrial Receptivity Following Assisted Reproductive Treatments, In Vitro Fertilization - Innovative Clinical and Laboratory Aspects, Prof. Shevach Friedler (Ed.), ISBN: 978-953-51-0503-9, InTech, Available from: http://www.intechopen.com/books/in-vitrofertilization-innovative-clinical-and-laboratory-aspects/the-role-of-ultrasound-in-the-evaluation-of-endometrialreceptivity-following-assisted-reproductive-[Last accessed 2017 Apr 5].  Back to cited text no. 2
    
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Deepika K, Pranesh GT, Rao KA, Sardana D, Upadhyay AJ. Correlation of sub endometrial-endometrial blood flow assessment by two-dimensional power Doppler with pregnancy outcome in frozen-thawed embryo transfer cycles. J Hum Reprod Sci 2014;7:130-5.  Back to cited text no. 3
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Mukhopadhyay I, Saha A, Nandi N. Prediction of outcome of conception cycle by Transvaginal Usg with help of Ussr and Ubp method in West Bengal. Int J Recent Sci Res 2015;6:4114-6.  Back to cited text no. 4
    
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Malhotra N, Malhotra J, Malhotra N, Rao JP, Mishra N. Endometrial Receptivity and Scoring for Prediction of Implantation and Newer Markers. DSJUOG 2010;4:433-40.  Back to cited text no. 6
    
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Strowitzki T, Germeyer A, Popovici R, von Wolff M. The human endometrium as a fertility-determining factor. Hum Reprod Update. 2006;12:617-30. Epub 2006 Jul 10. Review. PubMed PMID: 16832043. [PubMed].  Back to cited text no. 7
    
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Bassil S. Changes in endometrial thickness, width, length and pattern in predicting pregnancy outcome during ovarian stimulation in in vitro fertilization. Ultrasound Obstet Gynecol 2001;3:258-63.  Back to cited text no. 8
    
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Kovacs P, Matyas S, Boda K, Kaali SG. The effect of endometrial thickness on IVF/ICSI outcome. Hum Reprod 2003;11:2337-41.  Back to cited text no. 9
    
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Richter KS, Bugge KR, Bromer JG, Levy MJ. Relationship between endometrial thickness and embryo implantation, based on 1,294 cycles of in vitro fertilization with transfer of two blastocyst-stage embryos. Fertility and Sterility 2007;87:53-9.  Back to cited text no. 10
    
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Zhang X, Chen CH, Confino E, Barnes R, Milad M, Kazer RR. Increased endometrial thickness is associated with improved treatment outcome for selected patients undergoing in vitro fertilization-embryo transfer. Fertil Steril 2005;2:336-40.  Back to cited text no. 11
    
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Rinaldi L, Lisi F, Floccari A, Lisi R, Pepe G, Fishel S. Endometrial thickness as a predictor of pregnancy after in vitro fertilization but not after intracytoplasmatic sperm injection. Hum Reprod 1996;7:1538-41.  Back to cited text no. 12
    
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Brezinova J, Oborna I, Svobodova M, Fingerova H. Evaluation of day one embryo quality and IVF outcome--a comparison of two scoring systems. Reprod Biol Endocrinol 2009;7:9.  Back to cited text no. 13
    
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Fauque P, Leandri R, Merlet F, Juillard JC, Epelboin S, Guibert J, et al. Pregnancy outcome and live birth after IVF and ICSI according to embryo quality. J Assist Reprod Genet 2007;24:159-65.  Back to cited text no. 14
    
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Terriou P, Giorgetti C, Hans E, Salzmann J, Charles O, Cignetti L, et al. Relationship between even early cleavage and day 2 embryo score and assessment of their predictive value for pregnancy. Reprod Biomed Online 2007;14:294-9.   Back to cited text no. 15
    
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Terriou P, Sapin C, Giorgetti C, Hans E, Spach JL, Roulier R. Embryo score is a better predictor of pregnancy than the number of transferred embryos or female age. Fertil Steril 2001;75:525-31.  Back to cited text no. 16
    
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Pawel K. Optimal Environment for the Implantation of Human Embryo [Internet].www.intechopen.com 2012[last accessed 5 April 2017]. Available from: Paweł Kuć (2012). Optimal Environment for the Implantation of Human Embryo, The Human Embryo, Dr. Shigehito Yamada (Ed.), InTech, DOI: 10.5772/31810. Available from: https://www.intechopen.com/books/the-human-embryo/optimal-environment-for-the-implantation-of-human-embryo.  Back to cited text no. 17
    
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Eledessy MS, Abd El Naser M, Olma M, Almraghy Y. Endometrial Receptivity Score In Unexplained Infertility, Egyptian Journal of CHEST 2010;59:1-7.  Back to cited text no. 18
    
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Fanchin R, Righini C, Ayoubi JM, Olivennes F, De Ziegler D, Frydman R. New look at endometrial echogenicity: objective computer-assisted measurements predict endometrial receptivity in in vitro fertilization-embryo transfer. Fertil. Steril. 2000;74:274-81.  Back to cited text no. 19
    
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Yuval Y, Lipitz S, Dor J, Achiron R. The relationships between endometrial thickness, and blood flow and pregnancy rates in in-vitro fertilization. Hum. Reprod 1999;4:1067-71.  Back to cited text no. 20
    
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  Authors Top


Dr Navinchandra R Nayak is the man behind setting up of Dr Nayak' s Fertility Clinic who was born and brought up in Mumbai. Dr Nayak has done his MBBS and MD (OBG) from KMC, Manipal. He is also anointed as a Diplomat from the Indian College of Obstetricians and Gynecologists. He is certifi ed in gynecological endoscopy under the Women' s Health Initiative from JNH Chennai and from GTZ Germany. He is certifi ed in Advanced Gynecological Endoscopy and Management of Infertility from NILES Mumbai. He is certifi ed in Advanced Infertility Management from the Federation of Obstetrician and Gynecologists of India Mumbai and Dr Nadkarni' s IVF and Test tube Baby Centre, Gujarat. Dr Nayak has worked under various capacities at V N Desai Hospital Mumbai, Shatabdi Hospital in Mumbai, Sowkhya Nursing Home, Byndoor, Sri Ravalnath MSM Centre, Kaup and A J Hospital & Research Center, Mangalore. He has also served as an undergraduate and postgraduate teacher in Department of OBG at A J Institute of Medical Sciences & Research Center, Mangalore. He is a member of IMA, FOGSI and ISAR. He was the Charter President of Rotary Kaup, 2014 President of Mangalore Obstetrics & Gynaecological Society, Member of Endometriosis Committee of FOGSI 2015-16, Member of District Maternal Mortality Review Committee 2015-16 and Member of District Expert Committee for Perinatal Death Audit 2015-16. He is presently working in A.J.Institute of Medical Sciences,Mangalore as an Associate Professor and as an infertility specialist at Manipal Ankur Infertility Centre, Mangalore.



 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9]



 

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