The use of anti stretch marks’ products by women in pregnancy: a descriptive, cross-sectional survey
Brennan et al. BMC Pregnancy and Childbirth
The use of anti stretch marks' products by women in pregnancy: a descriptive, cross- sectional survey
Miriam Brennan 0
Mike Clarke 1
Declan Devane 0
0 School of Nursing & Midwifery, Aras Moyola, National University of Ireland Galway , Galway , Ireland
1 Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Institute of Clinical Sciences , Block B , Queen's University Belfast, Royal Hospital , Grosvenor Road, Belfast BT12 6BA , Northern Ireland
Background: Stretch marks (Striae gravidarum) are a cutaneous change occurring commonly during pregnancy. A variety of products are available and promoted as ways to prevent or reduce their development, but it is not clear what products are used most commonly. The objective of this study was to identify topical products used during pregnancy to prevent or reduce the development of striae gravidarum. We also explored issues around application of the product, cost incurred and influences on women's decisions to use a product. Methods: In this cross sectional, descriptive survey we collected data from 773 women, via a paper (n = 707) or online (n = 66) questionnaire. Due to missing data in the online survey, 753 women at 36 weeks gestation or more were included in the analyses. Descriptive and inferential statistical analyses were undertaken. Results: Most respondents (n = 589, 78.2 %) indicated that they used a product to prevent or reduce the development of stretch marks during their current pregnancy. A large range of products were used and more than one third of women (n = 210, 36.5 %) had used two or more products. Bio-oil was the most frequently used product (n = 351, 60.9 %) and it was also the most frequently used product among women who used only one product (n = 189, 32.8 %). Conclusions: Many women apply one of the many products available to prevent or reduce the development of striae gravidarum. Bio-oil was the most commonly used product identified in this study. There is a need for high-quality evidence on the effectiveness of Bio-oil and other products.
Pregnancy; Striae gravidarum; Topical products
Striae gravidarum, or stretch marks of pregnancy, are a
common cutaneous physiological change occurring during
]. They are considered the most common
connective tissue change of pregnancy [
] and affect both
primiparae and multiparae women. Women of all racial
groups are at risk [
]. Rates of occurrence vary [
reported rates ranging between 50 and 90 % [
gravidarum usually first appear around the sixth and
seventh month of pregnancy [
] but have being reported
prior to 24 weeks gestation [
]. They occur most
commonly during a first pregnancy but have been known
to occur for the first time in a second pregnancy [
vary in quantity and severity, frequently affecting the
], breasts and thighs where there is greatest
stretching of the skin [
Striae begin as 'reddish slightly depressed streaks’ [
which lighten in colour over time [
], fading [
leave glistening [
], or pale wrinkled lines [
] on the
skin by about 6 months after birth [
]. The exact
aetiology of striae remains unclear [
2, 5, 7, 8, 15–19
Possible explanations centre on stress on the tissue or
stretching of the skin and hormonal factors [
]. At a
micro level, it is suggested that changes occurring in the
collagen elastin and fibrillin, which contribute to the
tensile strength and elasticity of the skin [
significant factors in their development.
While the cause of striae remains unclear, certain
predisposing factors have been identified, albeit
inconsistently. They include an inherent susceptibility to developing
] or family history of striae [
7, 16, 21, 22
maternal weight gain [
5, 17, 22–24
], younger aged mothers
5, 17, 21, 24–26
], high pre-pregnancy body mass index
17, 22, 26
] and a high infant birth weight [
16, 17, 24
Younger mothers are more likely to develop striae and to
develop severe striae [
]. More recently, geographic
location and environmental factors  were found to
influence the development of striae, while age was not
found to be a predisposing factor [
Although striae are not considered a significant health
issue, they can affect women in different ways and may
cause distress to some women [
]. They may also cause
1, 7, 29
] or discomfort [
] while some refer to
them as ‘disfiguring’ [
3, 7, 13
] or as an aesthetic [
cosmetic concern [
5, 22, 30, 31
]. Some authors suggest
that striae impact on women's perception of themselves
and on their quality of life . However, a cross sectional
study on quality of life in Japanese pregnant women with
] found that general quality of life scores did
not differ between those with or without striae but that
women with severe striae had significant higher emotion
scores on the dermatology specific health related quality
of life instrument (HRQoL) Skindex −29 [
Interventions for stretch marks include those that
focus on prevention and those that focus on treatment
]. During pregnancy, the focus is on prevention of
striae or on reducing their severity and a wide range of
products are available purporting to prevent or minimize
the development of stretch marks. Consequently, women
may use these products during pregnancy, many of
which are considered cosmetic products [
significant expense [
]. However, the effectiveness of
many products is unclear [
] due to the limited amount
of research undertaken to date. A recent Cochrane
] which included six trials involving a total of
800 women, found no high-quality evidence to support
the use of any of the topical preparations identified in
the review for the prevention of stretch marks during
pregnancy. The authors recommended that preparations
commonly used by women to prevent and treat stretch
marks should be evaluated in large trials.
This cross sectional, descriptive survey, which is part
of a planned investigation of topical products to prevent
or reduce stretch marks in pregnancy, sought to identify
the topical products used during pregnancy to prevent
or reduce the development of striae gravidarum. We also
explored issues around application of product, costs
incurred and factors that influenced women's decision to
use a product.
We used a cross sectional, descriptive survey because of
its suitability for ascertaining viewpoints [
] at one
point in time [
]. Data were collected via a purposefully
developed questionnaire in both paper (main study) and
online format. The questionnaire contained 21 items
chosen after an extensive search of the literature on
stretch marks in pregnancy and discussions with
researchers and clinical staff [
]. The final
instrument had both open and closed ended items, included
'skip logic', and mainly addressed behaviours  in
relation to product application. Closed items required
participants to tick one or more options from a choice
of options [
]. The item seeking information on which
product, if any, participants used asked participants to
identify the product or products used by selecting 'all
that apply' from a list of commonly used products
generated from the literature and discussion with clinical staff.
Response options included an option to select ‘other’
and add narrative to identify a product respondent may
have used but which was not captured in listed response
options. A similar item stem and response options were
used for the item asking about information sources to
help women decide which product to use (Questionnaire
is available from MB).
Content validity testing, informed by the work of Lynn
] and Polit et al. [
], was undertaken with the
assistance of a panel of 12 experts. Criteria used for panel
selection were mainly methodological and clinical
expertise plus consumer representation. When tested, the
instrument was found to have good content validity with
each item having a content validity index value (I-CVI) ≥
0.83 while the entire instrument had a content validity
index of 0.94.
Data collection occurred over 16 months between July
2013 and April 2015. Data for the paper version were
collected by one author (MB) and two research assistants,
with support from staff in the antenatal clinic. Only one
data collector was present at any time. Women were
approached as they checked in or were waiting for their
routine antenatal appointment at 36 weeks or more
gestation. Almost all eligible women who were approached to
participate agreed to do so. Women attending parentcraft
sessions were recruited with the help of the parentcraft
team. Completed questionnaires were deposited by
women in a box on the clinic reception desk.
Potential participants were given information on the
study including its purpose and what participation
involved. Completion of the questionnaire was taken as
an explicit indication of consent to participate in the
study and this was outlined with the tenets of informed
consent in the first section of the questionnaire. The
online version of the questionnaire was supported by the
online provider SurveyMonkey™
(https://www.surveymonkey.com/). This study was approved by the Clinical
Research Ethics Committee for the Galway University
Hospitals Group and by the Research Ethics Committee
of the National University of Ireland Galway.
189 (32.8 %)
97 (16.8 %)
49 (8.5 %)
10 (1.7 %)
12 (2.1 %)
4 (0.7 %)
2 (0.3 %)
Numbers (%) using specific
product plus one or more
162 (28.1 %)
Participants were women who were at least 36 weeks
pregnant attending the antenatal clinic and parentcraft
education in a large regional hospital in the West of
Ireland. Only English speaking women were eligible to
participate, due to insufficient resources for translation
of study material. The sample size for distribution of the
main survey (paper questionnaire) was 692 women. This
was calculated based on a total population size of 3500
(average births per annum in the study site) and 95 %
confidence level, 5 % margin of error, which estimated a
required sample size of 346. This was doubled, based on
an assumption that the response rate would be 50 %. As
the likely population size for the online survey was
unknown, it was not possible to predetermine the sample
size for this mode of data collection because women were
notified through the maternity care advocacy groups and
the number of women in these groups is unknown.
As data quality is contingent on respondents being able
to understand what is being asked [
], pre testing and
piloting of the questionnaire was essential. Colleagues
assisted with this, specifically focusing on the
interpretation and clarity of questions [
]. A pilot study was also
undertaken to evaluate the questionnaire and the entire
survey process [
]. Respondents (n = 33) similar to
the intended main sample completed the questionnaire
and commented on the flow, length, ease of completion
and acceptability . No significant changes were
required to the questionnaire in relation to layout or
instructions following this preliminary testing.
Collected data were entered into SPSS version 21
] and checked and cleaned. Statistical
analysis involved both descriptive and inferential statistics.
Descriptive statistics included frequencies and measures
of central tendency and variation while inferential
statistics included Pearson Chi-square and Two proportion z
test to explore relationships and differences in relation
to product use between primigravida and multigravida
women. Data are reported for completed items i.e. we
did not impute missing values.
Of the 730 women asked to participate in the main survey,
707 agreed to do so, giving a response rate of 96.8 %. Of
the 66 women who completed the online version 20 were
ineligible because the woman’s gestation was not provided
or she was under 36 weeks gestation. This left 46
completed online questionnaires and an overall total of 753
eligible participants (707 paper version, and 46 online).
The mean gestational age of respondents was 38 weeks
(SD 1.5). First time mothers accounted for 40.2 % (n = 302)
of respondents while the majority of respondents (n = 449,
59.8 %) were expecting their second or subsequent baby
and the mean number of previous babies women had was
0.93. Most participants were Irish (n = 589, 78.3 %),
followed by Polish (n = 58, 7.7 %), and 35 other nationalities
were represented in the sample.
The majority of respondents (n = 589, 78.2 %) indicated
that they had used a product to prevent or reduce the
development of stretch marks during their current
pregnancy. Of the women who used a product and completed
the question on the use of specific skin products (n = 576,
98 %), 60.9 % (n = 351) used Bio-oil, followed by ‘other’
products (n = 202, 35.1 %), while the next most popular
product was cocoa butter cream, which was used by 174
(30.2 %) women and cocoa butter lotion used by 50 (8.7 %)
women (Table 1). A large range of products were included
by women in the 'other' category with examples including
baby oil (n = 31, 5.4 %), coconut oil (n = 16, 2.8 %) and
almond oil products (n = 11, 1.9 %). Respondents also
included some cocoa butter products (n = 4, 0.7 %) and many
Percent of overall
respondents (n = 576)
Numbers (%) using
specific product only
commercially available anti striae products in the 'other'
category. Cocoa butter products (cream, lotion and other)
were the second most popular product used (n = 228,
39.6 %). More than one-third of women (36.5 %, n = 210)
used two or more products. When comparing primigravida
and multigravida women, we found that significantly more
primigravida women reported using a product compared to
multigravida women (87.4 versus 72.2 %, X2 (1, n = 751)
=24.7, p =0.000) (Fig. 1). However, there was no significant
difference in the average number of products used
between primigravida and multigravida (mean
difference (MD) = 0.11, t (573) = 1.809, p = 0.071).
In relation to information sources that helped women to
choose a product, 49.3 % (n = 278) of women based their
decision on advice from friends, 23 % (n = 130) on product
advertisement, 18.8 % (n = 106) on advice from a family
member and 14.7 % (n = 83) on advice from the internet.
In relation to health care professionals the pharmacist was
the most frequently identified information source (n = 41,
7.3 %) followed by the general practitioner (GP) (3.4 %, n =
19) while midwives and obstetricians were consulted by
1.2 % (n = 7) and 0.2 % (n = 1) of women, respectively.
Some women identified that they had used the product in
a previous pregnancy or had got the product as a gift and
therefore did not choose the product deliberately or incur
any cost. Excluding the five (0.8 %) women who got the
product as a gift, the average amount spent by women on
products to prevent or reduce the development of stretch
marks was €16–20 per woman. We found an association
between the amount of money spent on skin products to
prevent or reduce the development of stretch marks
between primigravida and multigravida women. Significantly
more multigravida women spent < €5 on skin products
than primigravida (8.6 versus 3.8 % respectively, p = 0.015).
However, at the upper spending range, significantly more
primigravida women spent €51 or more when compared
with multigravida woman (15.2 versus 9.2 % respectively,
p = 0.029) (Table 2).
In this survey, 46.3 % (n = 342) of women had developed
stretch marks before their current pregnancy and 46.7 %
(n = 344) developed them during the current pregnancy.
Of all respondents, 209 (28.6 %) developed stretch marks
both before and during this current pregnancy (Fig. 2). On
comparing primigravida and multigravida women, 48.1 %
(n = 142) of primigravida and 45.9 % (n = 202) of
multigravida women developed stretch marks during
the current pregnancy. The majority of women (67.1 %,
n = 232) classified the amount they got during this
pregnancy as ‘a few’. A Chi-square test for independence
indicated no significant association between application of
a skin product to prevent the development of stretch
marks and the development of stretch marks during this
pregnancy (X2 (1, n = 737) = 2.174, p = 0.140), or with
having developed stretch marks prior to the pregnancy, X2
(1, n = 739) =3.179, p = 0.075. When comparing women
who developed stretch marks prior to and during the
current pregnancy versus those who did not develop
stretch marks prior to pregnancy but developed them
during the current pregnancy, we found that women who
developed stretch marks both prior to pregnancy and
during the current pregnancy were significantly more
likely to use cocoa butter lotion than those who did not
develop stretch marks prior to pregnancy but developed
them during the current pregnancy (11.0 versus 3.7 %
respectively, p = 0.016) (Fig. 3). In relation to Bio-oil, we
found those women without stretch marks prior to
pregnancy and who developed them during the current
pregnancy were significantly more likely to use Bio-oil
than women with stretch marks prior to and during the
current pregnancy (73.4 versus 58.5 % respectively,
p = 0.009) (Fig. 4). There was no difference in relation
to the other products like cocoa butter cream or olive oil.
Women were asked about the amount of time they
spent applying the product and how often they applied
it. Almost half of respondents (n = 262, 46.2 %) who
used a product and completed this question (n = 567)
had started to apply it in the first trimester and 266
(46.6 %) were applying it 7 days a week. The majority of
women (n = 398, 71.6 %) applied the product once a day
(women selected from a list of time options) and the
mean time spent applying it was 3.8 min (range: 29.9,
0.1 to 30 min; median: 2.5 min). There was no
significant association between the stage of pregnancy women
were at (≤20 weeks or > 20 weeks) when they started to
apply the product and being a primigravida or a
multigravida woman (X2 (1, n = 566) =0.944, p = 0.331)
nor was there a significant difference between the
average length of time spent per day applying the
product and being a primigravida or a multigravida
woman (MD = 0.459, t (558) = 1.52, p = 0.129).
However, there was a statistical significant difference
between the number of times per day the product was
applied and being a multigravida or a primigravida woman
(p < 0.05). The majority of mothers (primigravida and
multigravida) used the product once or twice a day.
However, more multigravida women used a product once a day
in comparison with primigravida women (75.7 versus
66.5 % respectively, p = 0.018) and more primigravida used
a product twice a day in comparison with multigravida
(29.5 versus 20.4 % respectively, p = 0.014) indicating that
(a) Developed stretch marks
before current pregnancy
(b) Developed stretch marks
during the current pregnancy
primigravida women were applying the product more
frequently during the day (Fig. 5).
The majority of respondents (75.5 %, n = 542)
indicated that their decision to use a product to prevent
stretch marks in pregnancy would be influenced by the
findings of a research study and 68.3 % (n = 514)
indicated that they would consider participating in a future
trial of a product to prevent or reduce stretch marks in
pregnancy. Further, significantly more primigravida
women would consider participating in a future trial
when compared with multigravida women (78.1 versus
67.0 % respectively, p = 0.001) (Fig. 6).
A large proportion of women in this survey used anti
striae products, with 78.2 % of women indicating that they
used one or more products to prevent or reduce the
development of stretch marks during pregnancy. This is
similar to a recent Japanese study [
] but higher than
that reported by others [
5, 26, 48
]. Similar to the
aforementioned Japanese study [
], we also found that
significantly more primigravida women than multigravida
women reported using a product to prevent stretch marks
in pregnancy. Furthermore, primigravida were also more
likely to spend more money and to apply the product
more frequently compared to multigravida women. This
suggests that primigravida women may be more motivated
to attempt prevention or reduction in severity of striae.
This is supported by our finding that primigravida women
would be more likely to consider participating in a future
trial compared to multigravida women.
A large range of products were used, as reported by
]. Similarly, the use of more than one
product has been identified by other researchers [
5, 22, 48
The most common product used by women in this study
was Bio-oil, which consists of a plant and vitamin extract
suspended in an oil base with fragrances and colouring
added. We do not know how representative this is of
other populations and occurs in the absence of
highquality evidence of the effectiveness of Bio-oil for the
prevention of stretch marks in pregnancy, although it
has been found to significantly improve stretch mark
appearance in an exploratory study of non pregnant
women . Bio-oil is marketed widely in the print and
electronic media and in recent years is more readily
available in diverse high street locations, which may
contribute to its popularity. One participant added how
you 'hear lots about Bio-oil everywhere'.
Cocoa butter products were also used by a large
proportion of women, as has been found by others [
] despite the
lack of evidence to demonstrate their effectiveness in
preventing striae gravidarum. One trial [
] that compared
cocoa butter cream to a placebo found no significant
difference between the control and intervention group. Similar
results were found for cocoa butter lotion [
butter is also present in some of the 'other products' used
by women in this study and the effectiveness of these and
the many other commercially available products used by
women remains uncertain [
]. Some women may also
have used cocoa butter lotion to prevent worsening of pre
existing striae based on our finding of its use by women
who developed stretch marks both prior to pregnancy and
during the current pregnancy. In relation to olive oil,
studies have yielded conflicting results. One early
observational study [
] found that it did not prevent striae in
primigravidae, but Davey [
] found in his non
experimental study that olive oil massaged into the skin was
associated with a lower incidence of stretch marks. More
recently, olive oil was evaluated in two trials [
neither supported its use for the prevention of striae
gravidarum. In contrast to olive oil, bitter almond oil, has been
found to be effective in a quasi-experimental study ,
which found that bitter almond oil and massage was
effective, not the almond oil on its own. The use of baby oil has
also been reported in other studies [
Women use various sources of information to help
them to make pregnancy related decisions [
] and this is
also true for anti striae products. Although other studies
have found that women often seek advice from midwives
and doctors on how to prevent striae [
] this was not
the case here. Advice from friends was the most
commonly identified source of information. The role of
friends, family and the internet has being identified by
others . Product advertisement was also influential in
this study [
]. There is increasing awareness of the role
of the internet to assist women in making decisions [
and women are using the internet to inform pregnancy
related choices [
], especially in the early part of
pregnancy . While midwives have been identified as very
important sources of information in pregnancy [
was not so in relation to anti stretch mark products but
this is not surprising as many women had decided on
which product to use in early pregnancy, before they had
come into contact with a midwife or obstetrician.
It is also possible that the lack of consultation with
health care professionals reflects the view that striae are
a cosmetic or aesthetic concern [
5, 17, 22, 30, 31
therefore, unlike other physiological changes that arise
in pregnancy, women might decide that they do not
merit discussion with the maternity care provider. The
majority of women using a product were applying it
once a day, which concurs with advice to women
participating in some studies [
3, 49, 51, 58
]. However, some
advocate application at least twice a day .
Many of the products that women reported using have
not been evaluated or, where they have been, have not
been shown to prevent stretch marks. The majority of
women in this survey indicated that they would be
influenced by research evidence on the effectiveness of
products for prevention or reduction of stretch marks in
pregnancy and would be willing to participate in a trial
of a product to prevent or reduce stretch marks in
pregnancy. This is promising given the need for such
evaluation and the recruitment problems for research studies
generally and trials in particular [
The sample size and high response rate are key
strengths of this study. Although the majority of the
women were Irish, other ethnic groups were represented.
Furthermore the sample closely represents the accessible
] and national population [
] for 2014 in terms of
women having their second or subsequent babies. They
accounted for 59.8 % of all women in this study, which is
very close to the accessible population (60.3 %) and the
national picture (62 %).
More women developed stretch marks during the
current pregnancy (46.7 %) than found in the Japanese
cross sectional study [
] which included both primiparae
and multiparae (39.1 %) but this was fewer than the
71.2 % of women who developed stretch marks found in a
Polish study [
This survey also has some limitations including a non
probability convenience sample that may not be truly
representative of all pregnant women and how
information provided by survey participants may be subject to
recall bias [
]. While many women were still using the
products, there may have been some bias with
information recall, for example in relation to amount of money
spent on products. Another possible consideration is that
we could have asked women to identify specifically where
they applied the anti striae product rather than asking a
generic question on the application of a product to their
skin to prevent stretch marks in pregnancy. Therefore,
some caution is necessary when interpreting the findings.
In conclusion, this is a large survey of women’s use of
products to prevent or reduce the development of striae in
pregnancy and highlights further the importance of preventing
or minimising stretch marks to many women. However,
there is a lack of high-quality evidence on the effectiveness
of the products being used. This study, which is part of a
planned investigation of topical products to prevent or
reduce the development of stretch marks in pregnancy,
follows on from the Cochrane Systematic Review exploring
the effects of topical preparations on the prevention of
stretch marks in pregnancy and provides the platform for a
future trial to investigate the effectiveness of such products.
It also provided us with an insight into the feasibility of
recruiting women to a future trial. Future trials evaluating
the effects of topical products on the prevention and
reduction of stretch marks in pregnancy are necessary and can
help to resolve the uncertainty around product efficacy and
provide women with the information they need to make
well-informed choices and to help health care professionals
who are asked for advice by women.
HRQoL: Health related quality of life
We wish to thank the staff at the antenatal clinic (including parentcraft
education team) at Galway University Hospital for permission to access the
site and collect data and the Maternity care advocacy groups (AIMS Ireland,
Cuidiu and Rollercoaster team) for access to participants. Also Aoife Ward
and Eve O Meara, two midwifery students who helped with data collection.
Finally, we would like to thank Davood Roshan for assistance with the
inferential statistical testing.
Funding was given towards the study by the School of Nursing & Midwifery,
National University of Ireland Galway.
Availability of data and material
Data are available from the corresponding author upon request.
MB, MC and DD conceived the study. MB developed the questionnaire with the
support of DD. MB was responsible for the data collection and did the data entry
into SPSS and did the descriptive analysis. MB prepared the initial manuscript
draft. MC and DD reviewed the manuscript at each stage and edited sections
accordingly. All the authors saw and approved the final version of this article.
MB is a Lecturer in Midwifery and PhD candidate at the School of Nursing &
Midwifery, National University of Ireland Galway.
MC is a Professor of Trial Methodology at Queen's University Belfast and
Director of All-Ireland Hub for Trials Methodology Research and Chair of the
MRC Network of Hubs for Trials Methodology Research.
DD is Professor of Midwifery at the National University of Ireland Galway and
Director of the Health Research Board -Trials Methodology Research Network
The authors declare that they have no competing interests.
Consent for publication
Ethics approval and consent to participate
This study involved the use of an anonymous questionnaire. Completion of the
questionnaire was taken as an explicit indication of consent to participate in
the study and this was outlined with the tenets of informed consent in the first
section of the questionnaire. This study was approved by the Clinical Research
Ethics Committee for the Galway University Hospitals Group and by the
Research Ethics Committee of the National University of Ireland Galway.
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