Risk factors for the development of striae gravidarum

ocrit. When the fetal platelet count is less than 50 10/L, a transfusion of concentrated platelets should be performed to prevent fatal exsanguination. We do not believe that it is necessary to transfuse platelets at cordocentesis prophylactically if the platelet count can be obtained in a few minutes and the procedure is continuously monitored with ultrasound. In such cases a cordocentesis would be preferable at the placental cord insertion. Although there are no clear data to support this suggestion, our experience leads us to believe that it might minimize the risk of bleeding. CLINICAL IMPLICATIONS


MATERIALS AND METHODS
A cross-sectional study was conducted at a large private teaching hospital in Beirut, Lebanon. All primiparas with singleton gestations delivering during a 6-month period (February through July 2005) were invited to participate in the study irrespective of gestational age at delivery.
All eligible participants were assessed postpartum with a 22-item data collection tool before hospital discharge. Information was collected from their medical charts about socioeconomic status, gestational age at delivery, total weight gain during pregnancy, current weight, fetal sex, and fetal birthweight. Patients admitted at the expense of the Ministry of Health were considered to be of low socioeconomic status: those with private insurance, of high socioeconomic status. Patients were asked whether they had used creams to prevent SG during pregnancy, smoking history, and family history of SG. Family history of SG was considered positive if the woman's mother and/or sister had developed SG during pregnancy. Skin type was determined by interview questions based on the Fitzpatrick classification, which categorizes skin according to the extent of tanning or burning with sun exposure.
One of 3 researchers assessed the presence of SG on the abdomen, thighs, and breasts based on a scale developed and validated by the research team. The scale is based on the totalsurfaceareaoftheaffectedbodypartthat is covered by SG: mild, Ͻ 25%; moderate, 25-50%; and severe, Ͼ 50%.
Assuming a 50% prevalence of SG, a total of 113 patients would be required to achieve a clinical significance of 15% at a power of 90% and a significance level of .05. The data were entered and analyzed using SPSS 13.0 (Chicago, IL). Two different outcomes were considered: (1) women with any SG (mild, moderate, or severe) on the abdomen, thighs, or breasts versus those with no SG in any of those sites; and (2) women with moderate and/or severe SG in any of the 3 sites versus women who had either mild SG or none.

RESULTS
During the study period, 532 women delivered at the hospital. Of these, 163 were eligible to participate in the study; 41 were discharged before they could be approached, and 9 did not wish to participate. One eligible woman was not approached because her infant was stillborn. Two other women were excluded from the final analysis because of missing information.
All eligible patients who were not formally assessed were compared to the women (n ϭ 110) included in the study. No significant differences were found in maternalage,socioeconomicstatus,gestationalage at delivery, fetal sex, or birthweight.
Most (93%) of the women in the study delivered at term. The majority (77%) of women were 24-34 years of age. Mean maternal age was 28 years. Weight gained during pregnancy ranged from 3 to 33 kg (mean, 14.4 kg). Birthweight ranged from 677 to 4115 grams (mean, 3143 g).
Women who developed SG were significantly younger and had gained significantly more weight during pregnancy than those who did not develop SG. Birthweight and gestational age at delivery were strongly associated with risk of developing moderate to severe SG.
The predominant skin types in our population were Fitzpatrick III (41%) and IV (32%). Most of the women (88%) were nonsmokers; 45% were of low socioeconomic status. Sixty-seven women (61%) had used a cream or lotion during pregnancy in an attempt to prevent SG.
Sixty-five (59%) of the infants delivered were male and 47 (43%) were female. No relationship was noted between skin type, socioeconomic status, smoking, cream use, fetal sex, or family history and the risk of developing SG. However, women with a family history of SG were more likely to develop moderate to severe SG than were those with no family history of SG (Table).

COMMENT
This study provides a clinical assessment of the prevalence of SG and associated risk factors in a cohort of racially homogeneous women at a single tertiary-care referral center. The evaluation was based  on a new scoring system developed by the researchers. This is 1 of the few studies in which SG were quantified by clinical assessment rather than relying on patient self-evaluation. To our knowledge, this is the only study that has evaluated SG on the breasts and thighs; others have focused only on the abdomen. We found that the prevalence of SG is 60%, consistent with reported figures. SG have a predilection to the abdomen, the site of involvement in 47% of the women; 24% hadSGonthethighsand/orbreasts.Thecorrelation we identified between weight gain during pregnancy and birthweight and the development of SG is consistent with findings by Davey. Although gestational age at delivery and birthweight were similar in women who developed SG and those who did not, both birthweight and gestational age at delivery were significantly greater for women whose SG was more severe.
Women with a positive family history of SG were more likely to develop moderate to severe SG, suggesting that genetic factors play a role in the development of SG. Unfortunately, our study population was too racially homogeneous to determine any differences with regard to SG risk related to skin type.
Similarly, our cohort contained too few smokers to correlate smoking with SG development. Fetal sex did not correlate with SG development.
A large proportion of our population had used at least 1 cream or lotion to prevent the development of SG; however, we found no correlation between cream use and SG development. Women using topical treatments probably began to apply them after noting the development of SG.
During prenatal visits, women often ask about their risk of developing SG and how to prevent them. Our findings can help physicians answer some of these questions in counseling patients. Future research should focus on preventive methods that may reduce the likelihood of SG development.

CLINICAL IMPLICATIONS
High birthweight, excessive weight gain during pregnancy, and family history (although not to a statistically significant extent) may increase the risk of developing striae gravidarum. Factors that seem to make no difference include socioeconomic status, skin type, and fetal sex. Physicians may wish to use these findings when counseling pregnant patients about SG. Future research should consider methods to prevent striae gravidarum from developing.