Human: 
You are an assistant for question-answering tasks.
Use the following pieces of retrieved context to answer
the question. If you don't know the answer, say that you
don't know. DON'T MAKE UP ANYTHING.

ORIGINAL CONTRIBUTIONS
Bariatric Surgery Reduces Serum Anti-mullerian Hormone
Levels in Obese Women With and Without Polycystic
Ovarian Syndrome.
Francesco Chiofalo1 & Cristina Ciuoli1 & Caterina Formichi1 & Federico Selmi1 &
Raffaella Forleo1 & Ornella Neri1 & Giuseppe Vuolo2 & Patrizia Paffetti1 & Furio Pacini1
# Springer Science+Business Media New York 2016
Abstract
Purpose Obesity in fertile women has negative effect on fer-
tility. Anti-mullerian hormone (AMH) represents a good index
of fertility, and it is considered a marker of ovarian reserve and
of polycystic ovarian syndrome (PCOS) gravity. Previous
studies evaluated the relationship between obesity and AMH
with contradictory results.
The aim of the study was to investigate the relationship
between obesity and AMH and the changes of AMH in obese
women in reproductive age submitted to bariatric surgery.
Materials and Methods Fifty-five obese patients between 18
and 39 years with (29 patients) and without PCOS (26 pa-
tients) were compared with a control group of normal weight
women with (24 patients) and without PCOS (19 patients).
Fourteen obese women with PCOS and 18 without PCOS
underwent to bariatric surgery. Serum AMH, testosterone, an-
drostenedione, and DHEAS were performed in all patients
before and 1 year after surgical intervention.
Results AMH was significantly higher in the PCOS groups
(p < 0.001), both in obese (5.84 ± 3.94 ng/ml) and non-obese
women (7.35 ± 4.39 ng/ml). AMH was positively related to

---

Results AMH was significantly higher in the PCOS groups
(p < 0.001), both in obese (5.84 ± 3.94 ng/ml) and non-obese
women (7.35 ± 4.39 ng/ml). AMH was positively related to
testosterone (p < 0.0001), androstenedione ( p =0 . 0 0 0 5 ) ,a n d
DHEAS (p = 0.003). After bariatric surgery, AMH levels were
reduced in the both PCOS ( p = 0.02) and non-PCOS group
(p =0 . 0 4 ) .
Conclusions AMH levels are elevated in PCOS patients re-
gardless of the body weight. Bariatric surgery is effective in
the normalization of AMH levels (a possible indirect marker
of better fertility) only in obese patients with PCOS.
Keywords Anti-mullerian hormone . Obesity . Bariatric
surgery . Polycystic ovarian syndrome
Introduction
Obesity is becoming an epidemic condition in developed
countries. In the USA, the prevalence of obesity has increased
from 15.3% in 1995 to 23.9% in 2005 [1]. Women, who are
more than twice severely obese as men, make up the majority
* Cristina Ciuoli
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Francesco Chiofalo
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Caterina Formichi
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Federico Selmi
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Raffaella Forleo
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Ornella Neri
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Giuseppe Vuolo
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Patrizia Paffetti
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
Furio Pacini
<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>
1 Department of Medical, Surgical and Neurological Sciences,
University of Siena, Viale M. Bracci 16, 53100 Siena, Italy
2 Department of Surgical Sciences, Bariatric Surgery Unit, University

---

1 Department of Medical, Surgical and Neurological Sciences,
University of Siena, Viale M. Bracci 16, 53100 Siena, Italy
2 Department of Surgical Sciences, Bariatric Surgery Unit, University
of Siena, Viale M. Bracci 16, 53100 Siena, Italy
OBES SURG
DOI 10.1007/s11695-016-2528-y

---

of bariatric surgery patients [2]. Fertility is often the reason for
young female patients seeking this type of treatment, because
it is known that obesity has negative effects on fertility and on
in vitro fertilization (IVF) outcomes [3, 4].
Obesity is often associated with polycystic ovarian syn-
drome (PCOS); its prevalence in PCOS women varies be-
tween 61 and 76% [5]. Women with PCOS may have reduced
fertility [6, 7] due to the associated endocrine and gynecologic
abnormalities that impact ovarian quality and function [ 6]. A
recent study by Hart and Doherty [ 7] showed that infertility is
ten times more common among women with PCOS in com-
parison to healthy controls.
Weight reduction has been shown to ameliorate fecundity
and hormonal state of obese patients [ 8], in particular bariatric
surgery, which leads to substantial weight loss, improves men-
strual regularity, and induces ovulation in 71.4% of obese
women [9]. Many recent studies have demonstrated that after
bariatric surgery, there is an increase of naturally conceived
pregnancy and a reduction of complications during pregnancy
or delivery [2], compared to patients who remain obese during
their pregnancy [ 10–13].
However, not all studies demonstrated improvements in
fertility outcomes with weight loss and the mechanisms for
improved reproductive functions are not well understood
[14–16].
Markers of ovarian reserve, including baseline FSH, estra-
diol, inhibin B, antral follicle count, and more recently anti-

---

improved reproductive functions are not well understood
[14–16].
Markers of ovarian reserve, including baseline FSH, estra-
diol, inhibin B, antral follicle count, and more recently anti-
mullerian hormone (AMH), have been used to counsel pa-
tients regarding in their reproductive outcomes [ 17].
AMH is a member of transforming growth factor- β
superfamily, secreted by granulosa cells of follicles under-
going gonadotropin-independent development. Its produc-
tion begins when follicles are recruited from the primor-
dial pool to become the primary follicles and it ends when
they reach the final size and differentiation state. The
highest values of AMH in women are reached after pu-
berty and subsequently decrease with age. A number of
investigators have shown that AMH can be used as a
biomarker of ovarian age and ovarian reserve and as a
marker in the diagnosis and medical treatment of PCOS
[18–21]. Serum AMH concentrations remain stable
throughout the menstrual cycle, which is a major advan-
tage over other markers of fertility such as FSH and in-
hibin [ 17]. Various studies have evaluated the association
between AMH and BMI, but reported contradictory re-
sults. Some of them have reported a significant inverse
correlation between AMH and BMI, others found no re-
lationship between AMH and BMI [14, 22–24]. The eval-
uation of AMH levels could be of clinical value in
predicting the success on IVF and naturally fertility. One

---

lationship between AMH and BMI [14, 22–24]. The eval-
uation of AMH levels could be of clinical value in
predicting the success on IVF and naturally fertility. One
preliminary study has been performed to evaluate AMH
changes after surgical weig ht loss in 16 patients (3 of
them in postmenopausal state), suggesting a decrease in
serum AMH, confirmed by another recent study in a larg-
er group of obese women submitted to sleeve gastrectomy
[18, 19].
Starting from these considerations, we aimed at inves-
tigating the relationship between obesity and AMH and
the variance of AMH in premenopausal obese women
submitted to bariatric surgery. For this purpose, we eval-
uated
anti-mullerian hormo ne in obese patients (with or
without PCOS) and we compared it with normal weight
patients (with and without PCOS). We evaluated also the
blood levels of AMH in a subgroup of patients submitted
to bariatric surgery.
Patients and Methods
We retrospectively studied 55 obese women followed at the
Department of Endocrinology of Siena University, aged be-
tween 18 and 39 years old (mean age 31 ± 5 years, mean BMI
45 ± 7 kg/m 2) selected to include, using the Rotterdam PCOS
criteria, a group with PCOS (29 patients; mean age 30 ± 6 years,
mean BMI 44 ± 7 kg/m 2) and another group without PCOS
(26 patients; mean age 33 ± 3 years, mean BMI 46 ± 6 kg/m 2).
The control groups consisted of 19 normal weight women
without PCOS (mean age 30 ± 6 years, mean BMI 22 ± 2 kg/

---

(26 patients; mean age 33 ± 3 years, mean BMI 46 ± 6 kg/m 2).
The control groups consisted of 19 normal weight women
without PCOS (mean age 30 ± 6 years, mean BMI 22 ± 2 kg/
m2) and 24 normal weight women with PCOS (mean age
27 ± 4 years, mean BMI 23 ± 3 kg/m 2).
Fourteen obese women in the PCOS group and 18
obese women in the non-PCOS group underwent bariatric
surgery and were evaluated 12 months after surgical in-
tervention (5/14 in the PCOS group submitted to sleeve
gastrectomy and 9/14 to Roux-en-Y gastric bypass
(RYGB); 5/18 in the non-PCOS group submitted to sleeve
gastrectomy, 1/18 to gastric banding, and 12/18 to Roux-
en-Y gastric bypass).
All patients were evaluated for serum AMH, testosterone,
androstenedione, DHEAS, insulin and glycaemia, HOMA in-
dex, and excess weight loss (EWL%) (only in bariatric surgery
group). In patients submitted to bariatric surgery, AMH, tes-
tosterone, androstenedione, and DHEAS were measured be-
fore and 12 months after surgery.
AMH was measured using the Gen II enzyme linked im-
munosorbent assay (ELISA) (Beckman Coulter) and was con-
sidered normal in reproductive age between 1 and 4 ng/ml.
Androstenedione and DHEAS were measured with a solid-
phase, competitive chemiluminescent enzyme immunoassay
(Immulite 2000). Testosterone was dosed using a chemilumi-
nescent immunoassay (Access Immunoassay System,
Beckman Coulter).
Exclusion criteria were estro -progestin, metformin, or
inhositol therapy and hyperprolactinaemia, Cushing syn-

---

nescent immunoassay (Access Immunoassay System,
Beckman Coulter).
Exclusion criteria were estro -progestin, metformin, or
inhositol therapy and hyperprolactinaemia, Cushing syn-
drome, hypothyroidism, or 21-hydroxylase deficiency.
OBES SURG

---

Statistical Analysis
Statistical analysis was performed using the Prism 5.0 soft-
ware. Between groups, comparisons were performed by
Student t test for unpaired data and by Mann –Whitney U test
according to a normal or a nonparametric distribution of the
variable tested, to compare more two groups, Kruskall-Wallis
test was performed with Dunn ’s post-test. Wilcoxon signed-
rank test was used to compare differences among the groups in
the change of AMH levels from the preoperative period to the
postoperative one. To test the effects of different variables
independently of a covariate, binary logistic regression analy-
sis was used and partial correlation coefficients were comput-
ed. A p value <0.05 was considered statistically significant.
Results
Anthropometric and biochemical data are shown in Table 1.
BMI was not statistically different in the obese group with and
without PCOS, similarly in normal weight women. Age was
not statistically different in all groups.
As shown in Fig. 1, AMH was significantly higher in the
PCOS groups ( p < 0.001), both in obese (5.84 ± 3.94 ng/ml)
and non-obese women (7.35 ± 4.39 ng/ml).
Both in PCOS obese and non-obese women, mean testos-
terone, DHEAS, and androstenedione levels were significant-
ly higher compared to normal weight and obese patients with-
out PCOS ( p < 0.05), as shown in Table 1.
AMH was negatively related to age ( p = 0.004) only in
obese and normal weight women without PCOS, but not in

---

out PCOS ( p < 0.05), as shown in Table 1.
AMH was negatively related to age ( p = 0.004) only in
obese and normal weight women without PCOS, but not in
patients affected by PCOS. AMH was positively related to
testosterone (p < 0.0001), androstenedione ( p =0 . 0 0 0 5 ) ,a n d
DHEAS ( p = 0.003). No relationship was found between
AMH and BMI, insulin, glycaemia, and HOMA index.
Mean weight loss after bariatric surgery (expressed as
EWL%) was 65 ± 19% and was not statistically different
between the PCOS and non-PCOS group. Twelve months
after bariatric surgery, AMH levels decreased in obese patients
with PCOS from 5.44 ± 3.74 to 4.25 ± 3.65 ng/ml ( p =0 . 0 2 )
and in obese patients without PCOS from 1.83 ± 1.04 to
1.36 ± 1.04 ng/ml ( p =0 . 0 4 ) .( F i g .2a, b). In both groups,
the difference of AMH expressed as Δ was not different be-
tween sleeve gastrectomy and RYGB patients and was not
correlated to EWL%. Also testosterone, androstenedione,
and DHEAS levels decreased significantly in obese patients
Table 1 Anthropometric and
hormonal measures in obese and
normal weight patients with and
without PCOS
Obese (55) Non-obese (43)
PCOS Non-PCOS PCOS Non-PCOS
N 29 26 24 19
Age (years) 30 ± 6 33 ± 3 27 ± 4 30 ± 6
BMI (kg/m2) 4 4±7 4 6±6 2 3±3 2 2±2
T (ng/ml) 0.54 ± 0.18** 0.41 ± 0.23 0.59 ± 0.27* 0.28 ± 0.14
DHEAS (μg/dl) 205.1 ± 78.9** 157 ± 93 214.7 ± 182.5* 133.7 ± 71.1
A (ng/ml) 4.29 ± 1.66** ,**** 2.69 ± 1.23*** 3.52 ± 1.21* 2.0 ± 1.4

---

T (ng/ml) 0.54 ± 0.18** 0.41 ± 0.23 0.59 ± 0.27* 0.28 ± 0.14
DHEAS (μg/dl) 205.1 ± 78.9** 157 ± 93 214.7 ± 182.5* 133.7 ± 71.1
A (ng/ml) 4.29 ± 1.66** ,**** 2.69 ± 1.23*** 3.52 ± 1.21* 2.0 ± 1.4
AMH (ng/ml) 5.84 ± 3.94** ,**** 2.14 ± 1.33*** 7.35 ± 4.39* 2.37 ± 2.2
Data are expressed as mean ± SD
PCOS policystic ovarian syndrome, BMI body mass index, T testosterone; A androstenedione, AMH anti-
mullerian hormone, DHEAS dehydroepiandrosterone sulphate
*p < 0.05 normal weight without PCOS vs normal weight with PCOS, ** p < 0.05 normal weight without PCOS
vs obese with PCOS, ***p < 0.05 normal weight with PCOS vs obese without PCOS, ****p < 0.05 obese without
PCOS vs obese with PCOS
Fig. 1 AMH levels in the four groups of patients
OBES SURG

---

with PCOS ( p < 0.05), while in obese patients without PCOS
only, DHEAS levels significantly decreased ( p <0 . 0 1 ) .
Discussion
Even though an increasing number of obese women re-
curs to bariatric surgery to ameliorate their fertility, up to
now, only clinical data demonstrated an increased number
of pregnancies after bariatric surgery, but no studies eval-
uated hormonal changes [ 19], or took in account the pres-
ence of PCOS. Nonetheless, few studies evaluated the
effect of obesity on ovarian reserve tests in patients with-
out PCOS [ 14, 23–25].
We investigated AMH levels in obese patients with and
without PCOS and we compared them with a control
group of normal weight women with or without PCOS.
We decided to evaluate AMH because this parameter is a
good index of ovarian reserve and PCOS gravity and is
independent of the menstrual cycle phase, unlike FSH,
LH, estradiol, and progesterone. No relationship was
found between AMH and BMI, but a negative correlation,
as expected, was found with age (but only in patients
without PCOS). A positive correlation was found between
AMH and androgen levels, but not with insulin and
HOMA index. This finding could be explained by the
observation that obese patients with and without PCOS
are both insulin-resistant.
Before bariatric surgery, AMH levels seemed to be influ-
enced by the presence of PCOS rather than obesity, although a
limitation of the study was the evaluation of BMI only and not

---

Before bariatric surgery, AMH levels seemed to be influ-
enced by the presence of PCOS rather than obesity, although a
limitation of the study was the evaluation of BMI only and not
body composition and waist circumference. However, after
bariatric surgery, there was a significant decrease in AMH
levels in both PCOS and non-PCOS patients. Thus, in this
situation, it is possible to speculate a role of weight loss on
the changes of AMH levels, although the mechanism involved
cannot be derived from the study.
As expected, after bariatric surgery, AMH levels decreased
in all except two obese patients with PCOS in association with
clinical and androgen level improvement (menstrual cycles,
reduction of Ferriman-Gallwey index) in agreement with
other studies, which evaluated only clinical improvement
[20, 26]. In our group, the only two patients who did not
demonstrate an AMH reduction were the two women with
A M Hl e v e l sh i g h e rt h a n1 0n g / m l .T h i si si na g r e e m e n tw i t h
the literature, where obese women with PCOS submitted to
low-caloric diet had changes in AMH inversely related to
baseline AMH [27]. The reduction of AMH levels after sur-
gical intervention in obese women without PCOS is difficult
to explain. Indeed, one would expect an increase of AMH
levels after weight loss according to improvement of fertility,
while we found the contrary. This apparent discrepancy may
be related to the rapid weight loss or related to rapid fall of

---

levels after weight loss according to improvement of fertility,
while we found the contrary. This apparent discrepancy may
be related to the rapid weight loss or related to rapid fall of
leptin levels typical after bariatric surgery. The result is in
agreement with a study including 16 patients submitted to
bariatric surgery. The author explains the significant reduction
on the basis of the catabolic state after surgery [18]. The same
result was confirmed by Bhandari et al. [ 19] in a larger obese
cohort submitted to sleeve gastrectomy. Despite the fact that
these studies were performed at 3 and 6 months after surgery
and our study was performed at 12 months after surgery, the
results were the same.
It should be interesting to evaluate HOMA index after sur-
gery and the correlation with changes of AMH, but insulin
levels were not available for all patients. It is known that obese
women ameliorate insulin resistance after weight loss [28],
independently of presence of PCOS, so we did not expect a
correlation between these two parameters (AMH and HOMA
index) also after surgery. Indeed, assuming that number of
patients is limited, we did not find differences in AMH and
androgen levels after sleeve gastrectomy or RYGB, neither
correlation with EWL%.
At this time, it is too early to advocate routine measurement
of AMH to obese patients undergoing to bariatric surgery.
Further prospective studies are needed to answer this question,
especially in obese patients without PCOS.

---

of AMH to obese patients undergoing to bariatric surgery.
Further prospective studies are needed to answer this question,
especially in obese patients without PCOS.
The message of our study is that AMH levels are elevated
in PCOS patients regardless of the body weight. Bariatric
surgery is effective in the normalization of the AMH levels
(a possible indirect marker of better fertility) only in obese
patients with PCOS, probably reflecting a direct role of body
weight loss.
Fig. 2 a (left) Changes in AMH
levels after bariatric surgery in
obese patients with PCOS. b
(right) Changes in AMH levels
after bariatric surgery in obese
patients without PCOS
OBES SURG

---

Acknowledgements None
Compliance with Ethical Standards
Conflict of Interest The authors declare that they have no conflict of
interest.
Ethical ApprovalFor this type of study, formal consent is not required.
Informed Consent Informed consent was obtained from all individual
participants included in the study.
References
1. Bessesen DH. Update on obes ity. J Clin Endocrinol Metab.
2008;93(6):2027–34.
2. Gosman GG, King WC, Schrope B, et al. Reproductive health of
women electing bariatric surgery. Fertil Steril. 2010;94(4):1426–31.
3. Maheshwari A, Stofberg L, Bhattacharya S. Effect of overweight
and obesity on assisted reproductive technology — a systematic re-
view. Hum Reprod Update. 2007;13(5):433–44.
4. Pournaras DJ, Manning L, Bidgood K, et al. Polycystic ovary syn-
drome is common in patients undergoing bariatric surgery in a
British center. Fertil Steril. 2010;94(2):e41.
5. Glueck CJ, Dharashivkar S, Wang P, et al. Obesity and extreme
obesity, manifest by ages 20 –24 years, continuing through 32 –
41 years in women, should alert physicians to the diagnostic likeli-
hood of polycystic ovary syndrome as a reversible underlying
endocrinopathy. Eur J Obstet Gynecol Reprod Biol. 2005;122(2):
206–12.
6. Hart R, Norman R. Polycystic ovarian syndrome — prognosis and
outcomes. Best Pract Res Clin Obstet Gynaecol. 2006;20(5):751 –
78.
7. Hart R, Doherty DA. The potential implications of a PCOS diag-
nosis on a woman ’s long-term health using data linkage. J Clin

---

outcomes. Best Pract Res Clin Obstet Gynaecol. 2006;20(5):751 –
78.
7. Hart R, Doherty DA. The potential implications of a PCOS diag-
nosis on a woman ’s long-term health using data linkage. J Clin
Endocrinol Metab. 2015;100(3):911–9.
8. Pandey S, Pandey S, Maheshwari A, et al. The impact of female
obesity on the outcome of fertility treatment. J Hum Reprod Sci.
2010;3(2):62–7.
9. Moran LJ, Norman RJ. The effect of bariatric surgery on female
reproductive function. J Clin Endocrinol Metab. 2012;97(12):
4352–4.
10. Patel JA, Colella JJ, Esaka E, et al. Improvement in infertility and
pregnancy outcomes after weight loss surgery. Med Clin North Am.
2007;91:515–28.
11. Maggard MA, Yermilov I, Li Z, et al. Pregnancy and fertility fol-
lowing bariatric surgery: a systematic review. J Am Med Assoc.
2008;300:2286–96.
12. Deitel M, Stone E, Kassam HA, et al. Gynecologic-obstetric chang-
es after loss of massive excess weight following bariatric surgery. J
Am Coll Nutr. 1988;7(2):147–53.
13. Kaska L, Kobiela J, Abacjew-Chmylko A, et al. Nutrition and preg-
nancy after bariatric surgery. ISRN Obes. 2013;2013:492060.
14. Freeman EW, Gracia CR, Sammel MD, et al. Association of anti-
mullerian hormone levels with obesity in late reproductive-age
women. Fertil Steril. 2007;87(1):101–6.
15. Halawaty S, ElKattan E, Azab H, et al. Effect of obesity on param-
eters of ovarian reserve in premenopausal women. J Obstet
Gynaecol Can. 2010;32(7):687–90.

---

15. Halawaty S, ElKattan E, Azab H, et al. Effect of obesity on param-
eters of ovarian reserve in premenopausal women. J Obstet
Gynaecol Can. 2010;32(7):687–90.
16. Ska łba P, Cygal A, Madej P, et al. Is the plasma anti-mullerian
hormone (AMH) level associated with body weight and metabolic
and hormonal disturbances in women with and without polycystic
ovary syndrome? Eur J Obstet Gynecol Reprod Biol. 2011;158(2):
254–9.
17. Usta T, Oral E. Is the measurement of anti-Müllerian hormone
essential? Curr Opin Obstet Gynecol. 2012;24(3):151 –7.
18. Merhi M. Relationship of bariatric surgery to Mullerian-inhibiting
substance levels. Fertil Steril. 2008;90:221–4.
19. Bhandari S, Ganguly I, Bhandari M, et al. Effect of sleeve gastrec-
tomy bariatric surgery-induced weight loss on serum AMH levels in
reproductive aged women. Gynecol Endocrinol. 2016;17:1 –4.
20. Escobar-Morreale HF, Botella-Carretero JI, Alvarez-Blasco F, et al.
The polycystic ovary syndrome associated with morbid obesity
may resolve after weight loss induced by bariatric surgery. J Clin
Endocrinol Metab. 2005;90(12):6364–9.
21
. Nybacka Å, Carlström K, Fabri F, et al. Serum antimullerian hor-
mone in response to dietary management and/or physical exercise
in overweight/obese women with polycystic ovary syndrome: sec-
ondary analysis of a randomized controlled trial. Fertil Steril.
2013;100(4):1096–102.
22. Georgopoulos NA, Saltamavros AD, Decavalas G, et al. Serum

---

ondary analysis of a randomized controlled trial. Fertil Steril.
2013;100(4):1096–102.
22. Georgopoulos NA, Saltamavros AD, Decavalas G, et al. Serum
AMH, FSH, and LH levels in PCOS. Fertil Steril. 2010;93(3):e13.
23. Su HI, Sammel MD, Freeman EW, et al. Body size affects measures
of ovarian reserve in late reproductive age women. Menopause.
2008;15(857–61):70.
24. Nakhuda GS. The role of mullerian inhibiting substance in female
reproduction. Curr Opin Obstet Gynecol. 2008;20(257 –64):71.
25. Merhi ZO. Impact of bariatric surgery on female reproduction.
Fertil Steril. 2009;92(5):1501–8.
26. Eid GM, Cottam DR, Velcu LM, et al. Effective treatment of poly-
cystic ovarian syndrome with Roux-en-Y gastric bypass. Surg Obes
Relat Dis. 2005;1(2):77–80.
27. Malinowski SS. Nutritional and metabolic complications of bariat-
ric surgery. Am J Med Sci. 2006;331(4):219 –25.
28. Bojsen-Møller KN. Mechanisms of improved glycaemic control
after Roux-en-Y gastric bypass. Dan Med J. 2015;62(4):B5057.
OBES SURG

---

Answer the question based on the above context: What is the mean and sd of AMH levels before bariatric surgery and after bariatric surgeryin?