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Advances in Social Sciences Research Journal – Vol.7, No.10
Publication Date: October 25, 2020
DOI:10.14738/assrj.710.9132.
Emarah, M. S. A., El-Nagger, M. A., El-Shabacy, A. & Qushwa, S. H. (2020). Hypothyroidism In Women With Recurrent Spontaneous
Abortion. Advances in Social Sciences Research Journal, 7(10)71-77.
Hypothyroidism In Women With Recurrent Spontaneous Abortion
Mohamed S. A. Emarah
MD, Benha Teaching Hospital, Egypt
Mohamed A. El-Naggar
MD, Benha Teaching Hospital, Egypt
Abeer El-Shabacy
MD, Benha Teaching Hospital, Egypt
Sahar H. Qushwa
MD, Benha Teaching Hospital, Egypt
ABSTRACT
Recurrent miscarriage, defined as loss of two or more consecutive
pregnancies, occurs in 1–2% of couples attempting to bear children. The
major causes of recurrent pregnancy loss (RPL) based on the literature
include parental structural chromosome rearrangement, immunologic
factors (i.e. antiphospholipid syndrome), thrombophilic factors (both
inherited and acquired), anatomic factors of uterine anomalies, and
endocrinologic disorders. Luteal phase defect, polycystic ovarian
syndrome (PCOS), diabetes mellitus, thyroid disease and
hyperprolactinemia are among the endocrinologic disorders implicated
in approximately 17% to 20% of RPL. The prevalence of hypothyroidism
in the general population of reproductive age is about 2-3%. The aim of
this study is to observe the benefit of screening for hypothyroidism
amongst women with recurrent spontaneous abortion early in the first
trimester. The study included one hundred and sixty (160) women, in
the reproductive age of life, where there ages ranged from 20 – 33 years,
and divided into two groups. Study group which included eighty (80),
non pregnant women with a history of two or more consecutive
spontaneous abortions early in the first trimester, with no living
children and control group which included eighty (80), non pregnant
women having one or more living children without any history of
abortion. Hypothyroidism was noted in ten (10) cases (12.5%) in the
study group and noted in two (2) cases (2.5%) in the control group with
a statistically significant difference (P < 0.01). The mean levels of TSH in
the study group was 22.71 ± 13.13 μIu/ml. Conclusion: Screening for
hypothyroidism has clinical significance and would help to reduce
miscarriage rate in women with recurrent spontaneous abortion.
Keywords: Hypothyroidism – Recurrent spontaneous abortion – TSH – Free
T3 – Free T4.
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Advances in Social Sciences Research Journal (ASSRJ)
INTRODUCTION
Vol.7, Issue 9, September-2020
Recurrent miscarriage, defined as loss of two or more consecutive pregnancies, occurs in 1 – 3% of
couples attempting to bear children(1). The major causes of recurrent pregnancy loss (RPL) based
on the literature include parental structural chromosome rearrangement, immunologic factors (i.e.
antiphospholipid syndrome), thrombophilic factors (both inherited and acquired), anatomic factors
of uterine anomalies, and endocrinologic disorders. Nevertheless a definite cause of RPL is
identified in only half of the couples(2). More than 50% of couples have unexplained recurrent
pregnancy loss (uRPL), in whom the cause and risk are not identifiable, and therefore are believed
to mostly experience RPL attributable to chance alone(3)
.
Luteal phase defect, polycystic ovarian syndrome (PCOS), diabetes mellitus, thyroid disease, and
hyperprolactinemia are among the endocrinologic disorders implicated in approximately 17% to
20% of RPL(4). The prevalence of hypothyroidism in the general population of reproductive age is
about 2 – 3%(5). Thyroid dysfunctions are common in women during reproductive age with the
prevalence of elevated TSH ranging from 4% to 9% and the prevalence of thyroid peroxidase
antibodies (TPO–Ab) ranging from 11.3% to 18% in the population(6). The American college of
Obstetrics and Gynecology Characterized overt hypothyroidism as an elevated TSH and low
circulating thyroid hormones (Free T4)(7). Normal physiologic changes during early pregnancy,
such as increased plasma blood volume, decreased iodine concentrations, and increased production
of thyroid–binding globulin, which binds circulating thyroid hormones, all lead to an amplified
demand placed on the thyroid during pregnancy to increase the production of thyroid hormones(8)
.
Effect of overt hypothyroidism include increased risk of miscarriage, low birth weight, premature
delivery, placental abruption, hypertensive disorders of pregnancy, and lower intelligence quotient
scores(9)
.
Aim of the work
The aim of this study is to observe the benefit of screening for hypothyroidism amongst women
with recurrent spontaneous abortion early in the first trimester.
SUBJECTS AND METHODS
This is a randomized controlled study, conducted at Benha Teaching Hospital in Egypt, during the
period from June 2019, to July 2020.
The study included one hundred and sixty (160) women in the reproductive age of life where their
ages ranged from 20 to 33 years, and divided into two groups:
1. Study group: this group included eighty (80), non pregnant women with a history of two or
more consecutive spontaneous abortions early in the first trimester, with no livingchildren.
2. Control group: this group included eighty (80), non pregnant women without any history of
spontaneous abortion and having one or more living children.
ELIGIBLE CRITERIA
Women with known thyroid disorders, diabetes mellitus, history suggestive of polycystic ovarian
syndrome (PCOS), known hyperprolactinemia or auto-immune disorders, history of cervical
incompetence or any other uterine pathology were excluded.
All women underwent a comprehensive medical evaluation including detailed history taking and
thorough physical examination.
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URL: http://dx.doi.org/10.14738/assrj.710.9132 73
Emarah, M. S. A., El-Nagger, M. A., El-Shabacy, A. & Qushwa, S. H. (2020). Hypothyroidism In Women With Recurrent Spontaneous Abortion. Advances in
Social Sciences Research Journal, 7(10) 71-77.
All women in both groups were investigated for thyroid stimulating hormone (TSH), free tri- iodothyroxin (F-T3) and free thyroxine (F–T4) levels.
SAMPLE PREPARATION
1. Collect blood specimens and separate the serum immediately.
2. Specimens may be stored refrigerated at(2–8°C)for 5 days. If storage time exceeds 5 days, store
frozen at (-20°C) for up to one month.
3. Avoid multiple freeze – thaw cycles.
4. Prior to assay, frozen sera should be completely thawed and mixed well.
5. Do not use grossly lipemic specimens.
PROCEDURE
Done through multiple steps starting by bringing all specimens and kit reagents to room
temperature (18-26°C), gently mixing and lastly reading absorbance on ELISA reader at 450 nm
within 15 minutes after adding the stopping solution.
Results were constructed through the standard curve, according to SIGMA ALDRICH COMPANY,
3050 PruG Street, St. Louis, M063703, USA, with expected values as follows:
TSH: Adult: 0.4 – 4.2 μIu/ml.
Free T4: Adult : 0.8 – 2.0 ng/dl.
Free T3: Adult : 2.3 – 4.2 pg/ml
RESULTS
Table (I): Shows that there were no significant statistical differences between the two groups for all
demographic variables.
Variable
Study group
Number = 80
Control group
Number = 80
P – value
Mean ± SD
OR
Number (%)
Mean ± SD
OR
Number (%)
Age (Years) 26.8 ± 4.9 26.7±5.3 0.985
BMI (kg/m2) 24.99 ± 4.79 25.28 ± 4.87 0.933
Residence:
Rural 38(47.5%) 40 (50%) 0.731
Urban 42(52.5%) 40 (50%)
Table (II): Shows that there were no statistically significant difference in the number of pregnancy
losses in the study group.
Study group Number
= (80)
Number of pregnancy
losses Percent P. value
38 Two 47.5%
0.731
42 Three or more 52.5%
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Advances in Social Sciences Research Journal (ASSRJ) Vol.7, Issue 9, September-2020
Table (III): Shows that, there was a statistically significant difference between the two groups as
regarding the number of positive cases for hypothyroidism.
Group
Positive cases for
hypothyroidism
(Number)
Percent
(%) P – value
Study group
Number = (80) 10 cases 12.5 (%)
< 0.01
Control group
Number = (80) 2 cases 2.5%
Figure (I): Shows number of positive cases of hypothyroidism in both groups.
Table (IV): Levels of TSH, Free T3 and Free T4 as regarding hypothyroidism and euthyroid women,
in both groups.
Variable
Study group (Number = 80) Control group (Number = 80)
Hypothyroidism Euthyroid Hypothyroidism Euthyroid
Number = 10
cases
Number = 70
cases
Number = 2
cases
Number = 78
cases
% = 12.5% % = 87.5% % = 2.5% % = 97.5%
TSH
0.4 – 4.2 μIu/mL 22.71 ± 13.13 1.87 ± 1.2 12.1 2.1±1.54
Free T3
2.3 – 4.3 pg/ml 1.45 ± 0.72 2.91 ± 1.99 1.69 3.08 ± 1.28
Free T4
0.8 – 2.0 ng/dl 0.59 ± 0.20 1.22 ± 0.72 0.64 1.45 ± 0.45
Page 5 of 7
URL: http://dx.doi.org/10.14738/assrj.710.9132 75
Emarah, M. S. A., El-Nagger, M. A., El-Shabacy, A. & Qushwa, S. H. (2020). Hypothyroidism In Women With Recurrent Spontaneous Abortion. Advances in
Social Sciences Research Journal, 7(10) 71-77.
DISCUSSION
During pregnancy proper maternal thyroid function is important for both mother and fetus(10)
. The
symptoms of thyroid disease are often less than obvious, many women with recurrent miscarriages
wonder whether they might have an untreated thyroid condition. Furthermore, increased
production of thyroid- binding globulin and the subsequent binding of circulating thyroxine result
from the increased level of estrogen that occurs in early pregnancy(11). In pregnant women with
limited thyroid reserves, hypothyroidism may be unmasked by these increased demands(12)
.
Dramatic changes in physiologic status occur during pregnancy, likewise, thyroid function is also
affected.
For example direct stimulation of the thyroid by TSH receptor binding of β–human chorionic
gonadotrophin, a hormone synthesized in rapidly increasing levels in early pregnancy, transiently
increases T4 production. In addition the iodine concentration decreases as a result of the increased
glomerular filtration rate(13). Women with hypothyroidism have decreased fertility(14), even if they
conceive, the risk of miscarriage is increased(15). Preconception or early pregnancy screening for
thyroid dysfunction has been proposed but is not widely accepted. However, measurement of
thyroid function should certainly be considered in those who are at high risk(16).
In the present study, the prevalence of hypothyroidism in women with recurrent spontaneous
abortion early in the first trimester is (12.5%), with a statistically significant difference. This agrees
with the two studies done by Dinesh et al.(17) and Khalid et al.(18) , where the prevalence rate of
hypothyroidism was 14.3% and 11.45% respectively.
Sharma et al.(19)
, found a significant association of thyroid function with an abortion rate of 14.63%
in their study group i.e. pregnant women with hypothyroidism and 4.96% in their control group. In
the study of Rama et al.(20); hypothyroidism was found in seven out of 163 (4.29%) women with
recurrent pregnancy loss and one out of 170 (0.58%) as control group. The study demonstrates that
hypothyroidism has a statically significant relationship with recurrent pregnancy loss in the first
trimester and suggests that diagnosis of hypothyroidism could help couples with RPL to have a
successful outcome in subsequent pregnancies.
In the study of Masand and Patel(21), hypothyroidism was found in seven out of one hundred (7%)
of women with recurrent pregnancy loss and in two out of one hundred (2%) as control group. The
study demonstrates that hypothyroidism has a statistically significant relationship with recurrent
pregnancy loss and concludes that screening for thyroid dysfunction should be done in all pregnant
and non pregnant women who had recurrent pregnancy losses necessarily during first trimester
itself soon after confirmation of pregnancy.
In the present study, the mean levels of TSH is 22.71 ± 13.13 μIu/mL.
In the two studies done by Alssandro et al.(22) and Verma et al.(23), the mean levels of TSH were 17.8
± 1.23 mIu/L and 29.8 ± 21.13 mIu/L respectively. A positive relationship was identified between
higher TSHin early pregnancy and the risk of child loss, defined as spontaneous abortion, fetal death
or neonatal death(24)
.