Is the sex of the baby associated with gestational diabetes risk?
A question that has been raised a few times in our Facebook support group, is the sex of the baby associated with gestational diabetes risk? Following a research study published yesterday in PLOS ONE, the question has risen once again.
Can gender really have an impact of whether you are more likely to develop gestational diabetes?
Over the last few years there have been a few studies on this and the answer concluded is yes!
There is an increased risk in developing gestational diabetes if you are expecting a boy…
A meta-analysis of 20 studies between 1 January 1950 and 4 April 2015 published in Diabetologia in November 2015, comparing data on 2,402,643 women showed that there is a 4% increased risk of gestational diabetes in women carrying boys.
We identified 320 studies through electronic searches and nine studies through manual searches. Twenty studies met the inclusion criteria, yielding data on 2,402,643 women. Pooled analysis of these studies demonstrated an increased risk of GDM in women carrying a male fetus compared with women carrying a female fetus (RR 1.04; 95% CI 1.02, 1.06). This result was confirmed in a sensitivity analysis including only studies that applied a stringent definition of GDM (RR 1.03; 95% CI 1.01, 1.06) (I 2 = 0%, p = 0.66).
Pregnant women carrying a boy have a 4% higher relative risk of GDM than those carrying a girl. The fetus thus may have previously unsuspected effects on maternal glucose metabolism in pregnancy.
A further study published in Diabetes Care in May 2015 on 1,074 pregnant women also showed an increased risk of gestational diabetes in those that were expecting boys…
Interaction Between Male Fetus and Classic GDM Risk Factors
To test for biological interaction between male fetus and classic risk factors for GDM (maternal age >35 years, nonwhite ethnicity, family history of diabetes, and prepregnancy overweight/obesity), we investigated whether the combined impact of male fetus and each of these risk factors on the likelihood of GDM exceeded the sum of their individual effects. Interaction was detected between sex of the fetus and maternal age (Table 3). Indeed, the presence of maternal age >35 years and male fetus conferred increments in the risk of GDM of 31.8 and 15.4%, respectively, as compared with the reference group (maternal age ≤35 years and female fetus). However, when both conditions were present, there was a 47.3% relative excess risk of GDM above and beyond the sum of these individual risks (Fig. 2A). Similarly, male fetus showed significant interaction with nonwhite ethnicity (Table 3), such that the combined effect with this risk factor was again greater than the sum of their individual risks (51.1% relative excess risk) (Fig. 2B). The analysis was equivocal as to whether there was interaction between male sex and family history of diabetes (Table 3), with only a very modest relative excess risk (Fig. 2C). With prepregnancy BMI, there was no interaction with male sex (RERI ∼0, AP ∼0, and S ∼1) (Table 3), yielding no increase in relative risk with both factors combined (Fig. 2D). In addition, the findings from the analyses in Fig. 2A–C were unchanged with further adjustment for prepregnancy BMI (data not shown).
RESULTS Women carrying a male fetus had lower mean adjusted β-cell function (insulinogenic index divided by HOMA of insulin resistance: 9.4 vs. 10.5, P = 0.007) and higher mean adjusted blood glucose at 30 min (P = 0.025), 1 h (P = 0.004), and 2 h (P = 0.02) during the OGTT, as compared with those carrying a female fetus. Furthermore, women carrying a male fetus had higher odds of developing GDM (odds ratio 1.39 [95% CI 1.01–1.90]). Indeed, male fetus further increased the relative risk of GDM conferred by the classic risk factors of maternal age >35 years and nonwhite ethnicity by 47 and 51%, respectively.
CONCLUSIONS Male fetus is associated with poorer β-cell function, higher postprandial glycemia, and an increased risk of GDM in the mother. Thus, fetal sex potentially may influence maternal glucose metabolism in pregnancy.
A study published yesterday, 11 July 2016 in PLOS ONE has once again found that having a boy can increase the risk of gestational diabetes, pre-term birth and pregnancy induced hypertensive disorders.
The study included 574,358 South Australian singleton live births during 1981–2011 and compared the incidence of three major adverse pregnancy outcomes; preterm birth, pregnancy induced hypertensive disorders and gestational diabetes mellitus in relation to fetal sex compared according to traditional and fetus-at-risk (FAR) approaches.
Having a boy can increase the risk, but we can’t change the gender of our babies!
Interesting studies, but whilst we can see that having a boy makes us slightly higher risk of gestational diabetes, we can’t change the gender of our babies and so it’s not a risk factor we can impact.
You can find out more about the associated risks to gestational diabetes, including some that you can impact on our main gestational diabetes page.