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H. Alsalem82
should be informed that weight loss between pregnancies reduces the risk of stillbirth, hypertensive complications and fetal macrosomia. Weight loss increases the
chances of successful vaginal birth after caesarean (VBAC) section.
2 Pre-pregnancy Supplementation
Women with a BMI 30 kg/m2 or greater wishing to become pregnant should be
advised to take 5 mg folic acid supplementation daily, starting at least 1 month
before conception and continuing during the first trimester of pregnancy. (RCOG).
Metabolic and nutritional derangements can occur after bariatric surgery, particularly after malabsorptive procedures. Reduced oral intake and alterations
in digestive physiology as well as anatomy can result in malabsorption of various micronutrients and minerals, particularly iron, folate, vitamin B12, calcium,
and vitamin D. Absorption of iron and folate are reduced due to lower acid content in the gastric pouch and bypass of the duodenum, the main site of absorption. Calcium deficiency can also result from bypass of the duodenum, as well as
reduced intake of both calcium and vitamin D. A reduction in the availability of
both gastric acid and intrinsic factor may lead to B12 deficiency.
While women with prior malabsorptive procedures are at greatest risk for
micronutrient deficiencies, women who undergo restrictive procedures may also
develop iron, folate, and fat soluble vitamin deficiencies [2].
A number of adverse pregnancy outcomes have been linked to inadequate supplementation and resultant micronutrient deficiencies. Iron and B12 deficiencies
have resulted in maternal anemia.
Specific supplementation regimens need to be tailored to the individual patient
and the type of bariatric procedure performed [3]. Guidelines for optimum micronutrient supplementation during pregnancy have been extrapolated from data from
the bariatric and obstetric literature. In general, during pregnancy, it is reasonable
to continue the regimen recommended by the bariatric surgeon, but the multivitamin is generally advised and is replaced with a prenatal vitamin.
It is generally advised that the following tests are to be performed pre conception or at booking antenatal visit [4]:
– Complete blood count
– Ferritin
– Iron
– Vitamin B12
– Thiamine
– Folate
– Calcium
– Vitamin D
The previous tests will aid in identifying those who will require additional supplementation as well as ensure followup during the course of the pregnancy. Monthly
The Sleeve and Pregnancy
83
repeat labs are also suggested to those with demonstrable deficiencies. At every
trimester, the tests should be repeated to those with no documented deficiency.
Supplementation and screening should continue following delivery in women
who breastfeed.
3 Acceptable Weight Changes in Pregnancy
There is a lack of consensus on optimal gestational weight gain in the obese
population or post weight management surgery group. Until further evidence is
achieved, the main advice by treating obstetrician is focus on a healthy diet that
is more applicable than prescribed weight gain targets. None the less, a referral
to a nutritionist could aid in managing both obese and post weight management
surgery patients. Caloric restriction during pregnancy is not recommended, even
if patients continue to be overweight after bariatric surgery, due to concerns that
caloric restriction might impair fetal growth [5]. Anti-obesity medications are not
recommended during pregnancy.
Optimal weight gain during pregnancy in women who have undergone bariatric surgery has not been studied. We suggest that women who are not achieving
the minimum weight gain standards suggested by the IOM (0.5 lb [0.23 kg]/week
for obese women in the second and third trimester) undergo ultrasound evaluation
of fetal growth and dietary consultation. If adequate caloric intake is confirmed,
we do not recommend encouraging the woman to consume significantly more
calories.
4 Care During Pregnancy
Routine care and management for post weight management surgery patients is
generally advise. Unless the starting (booking visit) BMI is elevated (>30 kg/m
then patient is to be followed up according to international guidelines for obese
patients.
Once again, the main issue with post weight management surgery patients is
attaining adequate nutrition. Nausea, vomiting might be more profound as the
gestation advances. It is most importantly to ensure adequate supplementations in
those patients. Needless to say, if symptoms persists, exclusion of acute causes is
mandatory.
It is well known that obesity in pregnancy carries risks to both the mother as
well as the fetus. Those risks can develop from early pregnancy till the post partum period. This includes early pregnancy loss, diabetes, hypertension, fetal macrosomia, failed induction of labor and ultimately undergoing a C-section. One
potential issue during pregnancy is obstructive sleep apnea. Once again no solid
evidence is found on the effect of wight management surgery specifically post
sleeve gastrectomy is found. We will review some of the potential risks of wight
management surgeries in the pregnant patient group.
2
),
H. Alsalem84
Fetal growth—Given the plausible increased risk of intrauterine growth
restriction and small for gestational age infants in post-bariatric surgery pregnancies, its been suggested to perform serial ultrasound examinations every four
weeks to evaluate fetal growth in the third trimester, especially in women with
poor weight gain and those who conceive within two years of surgery.
5 Gestational Diabetes
5.1 Screening
The glucose challenge test used to screen for gestational diabetes is typically
not well tolerated in women with prior history of bariatric surgery due to dumping syndrome which is experienced in about 50% of patients following RYGB.
It’s been suggested that following fasting and postbreakfast blood sugars for one
week as an alternative [6, 7]. Patients who regularly drink and tolerate sugared
soft drinks are an exception; these women probably can tolerate a standard glucose challenge test. A third option is to measure glycated hemoglobin (A1C) and
assume overt diabetes is present if it is elevated (≥6.5%); women with a normal
A1C should undergo screening as described.
Dumping syndrome typically does not occur in women who have undergone
restrictive-type bariatric procedures such as gastric banding and those women can
undergo standard testing for GDM.
5.2 Treatment
GDM conventional treatment involves nutritional therapy and insulin, some clinicians use oral anti-hyperglycemic agents, such as glyburide or metformin.
Monitoring for complications of bariatric surgery—The most common late
sequelae of bariatric surgery are mild nutritional deficiencies, which are readily
treated with replacement therapy.
5.3 Mode of Delivery
Cesarean delivery is performed for standard obstetric indications. Consultation
with a bariatric surgeon is advisable if the patient had a complicated bariatric surgery [5]. Patients who have undergone uncomplicated bariatric surgery generally
do not require changes in surgical technique. Some obstetricians may favor blunt
entry into the peritoneum to minimize risk of iviscus injury that could be adherent
to anterior abdominal wall.
The Sleeve and Pregnancy
85
5.4 Postpartum
Bariatric surgery should not adversely affect breast feeding and it should be
encouraged.
As previously disclosed, micronutrient supplementation and screening should
continue following delivery in women who breastfeed. Breastfed infants of women
who have had gastric bypass procedures may develop nutritional deficiencies,
especially those that are exclusively breastfed [7, 8].
References
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Tuomilehto J. The prevalence of overweight and obesity in an adult Kuwaiti population in
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Perinatol. 2009;29(9):640.
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The Sleeve and Reproductive Potential
Abdulrahman Alserri
1 Introduction
In this chapter we aim to cover the impact of obesity on both male and female
fertility potential and to touch upon the effect of bariatric surgery on natural and
assisted reproduction. The impact of obesity and bariatric surgery on pregnancy
will be discussed in a separate chapter.
2 Obesity and Female Reproduction
Women who are obese are at increased risk of menstrual abnormalities. It is also
noteworthy that menstrual irregularity is positively correlated with weight in obese
women [1]. This in turn prolongs the time to conception in obese women as the
spontaneous pregnancy rate decreases by about 4% for every kg/m2 increase in
BMI [2, 3].
A likely explanation for the lower spontaneous conception rate is the higher
prevalence of ovulation dysfunction (oligoovulation/anovulation) in obese women
[4]. Obese women with a BMI >27 kg/m2 are three times more likely to suffer
from anovulatory infertility compared to their lean counterparts [5]. The main
mechanism explaining this is a decreased gonadotropin secretion secondary to
negative feedback exerted from increased conversion of androgens to estrogens by
adipose aromatase [6–8].
A. Alserri (*)
Department of Obstetrics and Gynecology, Faculty of Medicine, Kuwait University, Kuwait
City, Kuwait
e-mail: a.alserri@HSC.EDU.KW
© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer
Nature Switzerland AG 2021
S. Al-Sabah et al. (eds.), Laparoscopic Sleeve Gastrectomy,
https://doi.org/10.1007/978-3-030-57373-7_11
87
A. Alserri88
Obese women also have more difficulty conceiving through assisted reproductive technologies (ART) compared to lean controls. A metanalysis of 33 In-VitroFertilization (IVF) studies that included 47,967 IVF cycles concluded that obese
women undergoing IVF have a lower chance of clinical pregnancy and live birth
as compared with normal weight women [9].
The mechanisms that may explain the difference in ART success are as follows:
1. Reduced response to fertility medications: When inducing ovulation, Obese
women require higher doses of medication and have a decreased chance of ovu-
lation. In IVF, they require a higher total dose of gonadotropins to stimulate the
ovaries, have fewer oocytes retrieved and have a higher cycle cancellation rate
[8, 10–17].
2. Reduced oocyte quality: In IVF, when using autologous oocytes, obese women
may experience altered oocyte morphology, lower fertilization, poorer embryo
quality and therefore lower pregnancy rates [10, 18–21]. However, when using
donor oocytes, obese women had better pregnancy rates [22, 23].
3. Altered endometrial function: Obesity appears to alter endometrial receptivity.
This has been shown when third-party surrogate women with a BMI >35 kg/
m2 experienced a 50% lower live birth rate compared with those with a BMI
<35 kg/m2 [24, 25].
4. Technical issues: Obesity may also make procedures such as ultrasound, oocyte
retrieval and embryo transfer, which are an essential part of ART success, more
difficult [26, 27].
3 Obesity and Male Reproduction
Obese men may suffer from altered sexual function and are more likely to have
erectile dysfunction [28–31]. They may also have poorer semen quality, where
studies have shown an increased likelihood of oligospermia and asthenospermia
[32–39]. However, the evidence is divided as to whether or not pregnancy outcomes are negatively impacted due to this [32, 39–45].
This is explained by increased androgen aromatization to estrogens by adipose tissue which in turn reduces gonadotropin secretion by the anterior pituitary
gland and thereby reducing both the production of testosterone and hindering normal spermatogenesis [29, 43, 46–52]. Semen parameters may also be adversely
affected by increased scrotal temperatures as the scrotum remains in closer contact
with the surrounding adiposity in obese men [43, 53].
4 Female Reproduction Following Bariatric Surgery
Female reproductive potential improves following weight loss. Improvement is more
pronounced in women with ovulation disorders specifically polycystic ovary syndrome
(PCOS) [54, 55]. This is true for both nonsurgical and surgical weight loss [56–61].
The Sleeve and Reproductive Potential
Weight loss following bariatric surgery may restore menstrual regularity and
promote ovulation [60, 62–64]. Furthermore, it has been shown to improve markers of PCOS specifically symptoms of hyperandrogenism like hirsutism, and
Insulin resistance [56, 60, 63, 65–71]. Further, a study looking specifically at laparoscopic sleeve gastrectomy (LSG) found that PCOS patients who had LSG had a
larger change in BMI at 1 year compared to controls without PCOS who had the
same procedure [72].
Sexual function in females has also been shown to be enhanced following bariatric surgery with women reporting improvement in libido [67].
Both the improvement in ovulation regularity and sexual function has translated
into better reproductive outcomes following bariatric surgery. It seems that the
amount of weight lost and the BMI at the time of conception were both predictors
of the chance of pregnancy following bariatric surgery but not the type of surgery
itself [73–75].
However, even given this encouraging data, bariatric surgery should not be the
primary treatment for infertility in obese women [76, 77].
89
5 Male Reproduction Following Bariatric Surgery
Weight loss following bariatric surgery may improve sexual function in some men
as it increases gonadotropin secretion as a result of decreased adipose aromatization of androgens to estrogens. It is however not clear whether weight loss following bariatric surgery alters sperm parameters [78]. Some case reports have
shown worsening semen parameters after bariatric surgery, possibly secondary to
nutritional deficiencies affecting normal spermatogenesis [79, 80]. Other reports
have shown that semen parameters remain stable after 1 year of follow up following bariatric surgery [81]. Therefore, in selected cases, men wishing to undergo
bariatric surgery may want to consider semen cryopreservation before surgery as a
back-up for future use [82].
6 Timing of Conception Following Bariatric Surgery
It is recommended that pregnancy be delayed until 1–2 years after bariatric surgery [36, 83–87]. This is to avoid the adverse effects of fetal exposure to nutritional deficiencies and rapid weight loss, and to optimize weight loss goals [57,
85]. If conception does occur before the recommended 1–2 years, there is lim-
ited data that suggests that surgery may not necessarily affect maternal and fetal
health given proper pregnancy surveillance [75, 88, 89]. A study specifically looking at the time interval between laparoscopic sleeve gastrectomy and pregnancy
found no difference in pregnancy outcome between women in the short interval
group (within 18 months) versus those in the long interval group (after 18 months)
[90]. In our opinion, time of conception should be individualized according to the
patient’s age, ovarian reserve and, if any, complications of surgery.
A. Alserri90
7 Assisted Reproductive Technologies (ART) Following
Bariatric Surgery
According to a case series of five women who underwent in-vitro fertilization
(IVF) 1–5 years after bariatric surgery, four out of the five women became pregnant and delivered at term without complications, suggesting that ART seems to be
safe following bariatric surgery [91].
8 Conclusion
We conclude that obesity has a negative effect on both male and female fertility.
In women, weight loss following surgery may be associated with improvement in
reproductive potential and pregnancy rates. In men, weight loss following surgery
may improve sexual function, but it is unclear if semen parameters are affected.
That said, bariatric surgery should not be recommended as the primary treatment
for male or female infertility.
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